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New submissions for Tue, 7 Apr 20
- [1] arXiv:2004.01711 [pdf, other]
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Title: Optical and X-ray discovery of the changing-look AGN IRAS23226-3843 showing extremely broad and double-peaked Balmer profilesAuthors: W. Kollatschny, D. Grupe, M.L. Parker, M. W. Ochmann, N. Schartel, E. Herwig, S. Komossa, E. Romero-Colmenero, M. Santos-LleoComments: 17 pages, 10 figures, Astronomy & Astrophysics in press. arXiv admin note: text overlap with arXiv:1804.05911Subjects: Astrophysics of Galaxies (astro-ph.GA); High Energy Astrophysical Phenomena (astro-ph.HE)
We detected a very strong X-ray decline in the galaxy IRAS23226-3843 within the XMM-Newton slew survey in 2017. Subsequently, we carried out multi-band follow-up studies to investigate this fading galaxy in more detail. We took deep follow-up Swift, XMM-Newton, and NuSTAR observations in combination with optical SALT spectra of IRAS23226-3843 in 2017. In addition, we reinspected optical, UV, and X-ray data that were taken in the past. IRAS23226-3843 decreased in X-rays by a factor of more than 30 with respect to ROSAT and Swift data taken 10 to 27 years before. The broadband XMM-Newton/NuSTAR spectrum is power-law dominated, with a contribution from photoionized emission from cold gas, likely the outer accretion disk or torus. The optical continuum decreased by 60 percent and the Balmer line intensities decreased by 50 percent between 1999 and 2017. The optical Seyfert spectral type changed simultaneously with the X-ray flux from a clear broad-line Seyfert 1 type in 1999 to a Seyfert 1.9 type in 2017. The Balmer line profiles in IRAS23226-3843 are extremely broad. The profiles during the minimum state indicate that they originate in an accretion disk. The unusual flat Balmer decrement Ha/Hb with a value of 2 indicates a very high hydrogen density of n_(H) > 10 exp(11) cm^(-3) at the center of the accretion disk. IRAS23226-3843 shows unusually strong FeII blends with respect to the broad line widths, in contrast to what is known from Eigenvector 1 studies.
- [2] arXiv:2004.01717 [pdf, other]
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Title: Atacama Compact Array Measurements of the Molecular Mass in the NGC 5044 Cooling Flow GroupAuthors: Gerrit Schellenberger, Laurence P. David, Jan Vrtilek, Ewan O'Sullivan, Jeremy Lim, William Forman, Ming Sun, Francoise Combes, Philippe Salome, Christine Jones, Simona Giacintucci, Alastair Edge, Fabio Gastaldello, Pasquale Temi, Fabrizio Brighenti, Sandro BardelliComments: 23 pages, 16 figuresSubjects: Astrophysics of Galaxies (astro-ph.GA)
The fate of cooling gas in the centers of galaxy clusters and groups is still not well understood, as is also the case for the complex processes of triggering star formation in central dominant galaxies (CDGs), re-heating of cooled gas by AGN, and the triggering/feeding of supermassive black hole outbursts. We present CO observations of the early type galaxy NGC 5044, which resides at the center of an X-ray bright group with a moderate cooling flow. For our analysis we combine CO(2-1) data from the 7m antennae of the Atacama Compact Array (ACA), and the ACA total power array (TP). We demonstrate, using the 7m array data, that we can recover the total flux inferred from IRAM 30m single dish observations, which corresponds to a total molecular mass of about 4x10^7 Msun. Most of the recovered flux is blueshifted with respect to the galaxy rest frame and is extended on kpc-scales, suggesting low filling factor dispersed clouds. We find 8 concentrations of molecular gas out to a radius of 10 arcsec (1.5 kpc), which we identify with giant molecular clouds. The total molecular gas mass is more centrally concentrated than the X-ray emitting gas, but extended in the north-east/south-west direction beyond the IRAM 30m beam. We also compare the spatial extent of the molecular gas to the Halpha emission: The CO emission coincides with the very bright Halpha region in the center. We do not detect CO emission in the fainter Halpha regions. Furthermore, we find two CO absorption features spatially located at the center of the galaxy, within 5 pc projected distance of the AGN, infalling at 255 and 265 km/s relative to the AGN. This indicates that the two giant molecular clouds seen in absorption are most likely within the sphere of influence of the supermassive black hole.
- [3] arXiv:2004.01721 [pdf, other]
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Title: A joint SZ-Xray-optical analysis of the dynamical state of 288 massive galaxy clustersAuthors: A. Zenteno, D. Hernandez-Lang, M. Klein, C. Vergara Cervantes, D. L. Hollowood, S. Bhargava, A. Palmese, V. Strazzullo, A. K. Romer, J. J. Mohr, T. Jeltema, A. Saro, C. Lidman, D. Gruen, V. Ojeda, A. Katzenberger, M. Aguena, S. Allam, S. Avila, E. Bertin, D. Brooks, E. Buckley-Geer, D. L. Burke, A. Carnero Rosell, M. Carrasco Kind, J. Carretero, F. J. Castander, M. Costanzi, L. N. da Costa, J. De Vicente, S. Desai, H. T. Diehl, P. Doel, T. F. Eifler, A. E. Evrard, B. Flaugher, B. Floyd, P. Fosalba, J. Frieman, J. García-Bellido, D. W. Gerdes, J.R. Gonzalez, R. A. Gruendl, J. Gschwend, G. Gutierrez, W. G. Hartley, S. R. Hinton, K. Honscheid, D. J. James, K. Kuehn, O. Lahav, M. Lima, M. A. G. Maia, M. March, M. McDonald, P. Melchior, F. Menanteau, R. Miquel, R. L. C. Ogando, F. Paz-Chinchón, et al. (17 additional authors not shown)Comments: 21 pages, 12 Figures, 4 Tables. Submitted to MNRASSubjects: Astrophysics of Galaxies (astro-ph.GA); Cosmology and Nongalactic Astrophysics (astro-ph.CO)
We use imaging from the first three years of the Dark Energy Survey to characterize the dynamical state of 288 galaxy clusters at $0.1 \lesssim z \lesssim 0.9$ detected in the South Pole Telescope (SPT) Sunyaev-Zeldovich (SZ) effect survey (SPT-SZ). We examine spatial offsets between the position of the brightest cluster galaxy (BCG) and the center of the gas distribution as traced by the SPT-SZ centroid and by the X-ray centroid/peak position from Chandra and XMM data. We show that the radial distribution of offsets provides no evidence that SPT SZ-selected cluster samples include a higher fraction of mergers than X-ray-selected cluster samples. We use the offsets to classify the dynamical state of the clusters, selecting the 43 most disturbed clusters, with half of those at $z \gtrsim 0.5$, a region seldom explored previously. We find that Schechter function fits to the galaxy population in disturbed clusters and relaxed clusters differ at $z>0.55$ but not at lower redshifts. Disturbed clusters at $z>0.55$ have steeper faint-end slopes and brighter characteristic magnitudes. Within the same redshift range, we find that the BCGs in relaxed clusters tend to be brighter than the BCGs in disturbed samples, while in agreement in the lower redshift bin. Possible explanations includes a higher merger rate, and a more efficient dynamical friction at high redshift. The red-sequence population is less affected by the cluster dynamical state than the general galaxy population.
- [4] arXiv:2004.01724 [pdf, other]
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Title: Free-form Grale lens inversion of galaxy clusters with up to 1000 multiple imagesComments: 18 pages, 12 figures, MNRAS, in pressSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
In the near future, ultra deep observations of galaxy clusters with HST or JWST will uncover $300-1000$ lensed multiple images, increasing the current count per cluster by up to an order of magnitude. This will further refine our view of clusters, leading to a more accurate and precise mapping of the total and dark matter distribution in clusters, and enabling a better understanding of background galaxy population and their luminosity functions. However, to effectively use that many images as input to lens inversion will require a re-evaluation of, and possibly upgrades to the existing methods. In this paper we scrutinize the performance of the free-form lens inversion method Grale in the regime of $150-1000$ input images, using synthetic massive galaxy clusters. Our results show that with an increasing number of input images, Grale produces improved reconstructed mass distributions, with the fraction of the lens plane recovered at better than $10\%$ accuracy increasing from $40-50\%$ for $\sim\!\!150$ images to $65\%$ for $\sim\!1000$ images. The reconstructed time delays imply a more precise measurement of $H_0$, with $\lesssim 1\%$ bias. While the fidelity of the reconstruction improves with the increasing number of multiple images used as model constraints, $\sim 150$ to $\sim 1000$, the lens plane rms deteriorates from $\sim 0.11''$ to $\sim 0.28''$. Since lens plane rms is not necessarily the best indicator of the quality of the mass reconstructions, looking for an alternative indicator is warranted.
- [5] arXiv:2004.01726 [pdf, other]
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Title: LOFAR 144-MHz follow-up observations of GW170817Authors: J. W. Broderick, T. W. Shimwell, K. Gourdji, A. Rowlinson, S. Nissanke, K. Hotokezaka, P. G. Jonker, C. Tasse, M. J. Hardcastle, J. B. R. Oonk, R. P. Fender, R. A. M. J. Wijers, A. Shulevski, A. J. Stewart, S. ter Veen, V. A. Moss, M. H. D. van der Wiel, D. A. Nichols, A. Piette, M. E. Bell, D. Carbone, S. Corbel, J. Eislöffel, J.-M. Grießmeier, E. F. Keane, C. J. Law, T. Muñoz-Darias, M. Pietka, M. Serylak, A. J. van der Horst, J. van Leeuwen, R. Wijnands, P. Zarka, J. M. Anderson, M. J. Bentum, R. Blaauw, W. N. Brouw, M. Brüggen, B. Ciardi, M. de Vos, S. Duscha, R. A. Fallows, T. M. O. Franzen, M. A. Garrett, A. W. Gunst, M. Hoeft, J. R. Hörandel, M. Iacobelli, E. Jütte, L. V. E. Koopmans, A. Krankowski, P. Maat, G. Mann, H. Mulder, A. Nelles, H. Paas, M. Pandey-Pommier, et al. (12 additional authors not shown)Comments: 9 pages, 2 figures, accepted for publication in MNRASSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
We present low-radio-frequency follow-up observations of AT 2017gfo, the electromagnetic counterpart of GW170817, which was the first binary neutron star merger to be detected by Advanced LIGO-Virgo. These data, with a central frequency of 144 MHz, were obtained with LOFAR, the Low-Frequency Array. The maximum elevation of the target is just 13.7 degrees when observed with LOFAR, making our observations particularly challenging to calibrate and significantly limiting the achievable sensitivity. On time-scales of 130-138 and 371-374 days after the merger event, we obtain 3$\sigma$ upper limits for the afterglow component of 6.6 and 19.5 mJy beam$^{-1}$, respectively. Using our best upper limit and previously published, contemporaneous higher-frequency radio data, we place a limit on any potential steepening of the radio spectrum between 610 and 144 MHz: the two-point spectral index $\alpha^{610}_{144} \gtrsim -2.5$. We also show that LOFAR can detect the afterglows of future binary neutron star merger events occurring at more favourable elevations.
- [6] arXiv:2004.01727 [pdf, other]
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Title: Phase Decoherence of Gravitational Wave BackgroundsComments: 5 pages, 3 figuresSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Instrumentation and Methods for Astrophysics (astro-ph.IM); General Relativity and Quantum Cosmology (gr-qc)
Metric perturbations affect the phase of gravitational waves as they propagate through the inhomogeneous universe. This effect causes Stochastic Gravitational Wave Backgrounds (SGWBs) to lose any phase coherence that may have been present at emission or horizon entry. We show that, for a standard cosmological model, this implies complete loss of coherence above frequencies $f \sim 10^{-12}$ Hz. The result is that any attempts to map SGWBs using phase-coherent methods have no foreseeable applications. Incoherent methods that solve directly for the intensity of the SGWBs are the only methods that can reconstruct the angular dependence of any SGWB.
- [7] arXiv:2004.01745 [pdf, other]
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Title: Solid accretion onto planetary cores in radiative disksComments: 8 pages, 9 figures, accepted for publication on A&ASubjects: Earth and Planetary Astrophysics (astro-ph.EP)
The solid accretion rate, necessary to grow gas giant planetary cores within the disk lifetime, has been a major constraint for theories of planet formation. We tested the solid accretion rate efficiency on planetary cores of different masses embedded in their birth disk, by means of 3D radiation-hydrodynamics, where we followed the evolution of a swarm of embedded solids of different sizes. We found that using a realistic equation of state and radiative cooling, the disk at 5 au is able to cool efficiently and reduce its aspect ratio. As a result, the pebble isolation mass is reached before the core grows to 10 Earth masses, stopping efficiently the pebble flux and creating a transition disk. Moreover, the reduced isolation mass halts the solid accretion before the core reaches the critical mass, leading to a barrier to giant planet formation, and it explains the large abundance of super-Earth planets in the observed population.
- [8] arXiv:2004.01751 [pdf, other]
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Title: Discriminating Accretion States via Rotational Symmetry in Simulated Polarimetric Images of M87Comments: 11 pages, 7 figures. Accepted into ApJSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
In April 2017, the Event Horizon Telescope observed the shadow of the supermassive black hole at the core of the elliptical galaxy Messier 87. While the original image was constructed from measurements of the total intensity, full polarimetric data were also collected, and linear polarimetric images are expected in the near future. We propose a modal image decomposition of the linear polarization field into basis functions with varying azimuthal dependence of the electric vector position angle. We apply this decomposition to images of ray traced general relativistic magnetohydrodynamics simulations of the Messier 87 accretion disk. For simulated images that are physically consistent with previous observations, the magnitude of the coefficient associated with rotational symmetry, $\beta_2$, is a useful discriminator between accretion states. We find that at 20 $\mu$as resolution, $|\beta_2|$ is greater than 0.2 only for models of disks with horizon-scale magnetic pressures large enough to disrupt steady accretion. We also find that images with a more radially directed electric vector position angle correspond to models with higher black hole spin. Our analysis demonstrates the utility of the proposed decomposition as a diagnostic framework to improve constraints on theoretical models.
- [9] arXiv:2004.01756 [pdf]
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Title: Thermal Evolution of Uranus with a Frozen InteriorComments: 17 pages, 8 figuresSubjects: Earth and Planetary Astrophysics (astro-ph.EP)
The intrinsic luminosity of Uranus is a factor of 10 less than that of Neptune, an observation that standard giant planetary evolution models, which assume negligible viscosity, fail to capture. Here we show that more than half of the interior of Uranus is likely to be in a solid state, and that thermal evolution models that account for this high viscosity region satisfy the observed faintness of Uranus by storing accretional heat deep in the interior. A frozen interior also explains the quality factor of Uranus required by the evolution of the orbits of its satellites.
- [10] arXiv:2004.01758 [pdf, other]
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Title: Photometric and Kinematic study of the three intermediate age open clusters NGC 381, NGC 2360, and Berkeley 68Comments: This article is accepted for publication in MNRASSubjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA)
We present UBVRcIc photometric study of three intermediate age open star clusters NGC 381, NGC 2360, and Berkeley 68 (Be 68). We examine the cluster membership of stars using recently released Gaia DR2 proper motions and obtain a total of 116, 332, and 264 member stars in these three clusters. The mean reddening of E(B - V) = 0.36+/-0.04, 0.08+/-0.03, and 0.52+/-0.04 mag are found in the direction of these clusters where we observe an anomalous reddening towards NGC 381. We fitted the solar metallicity isochrones to determine age and distance of the clusters which are found to be log(Age) = 8.65+/-0.05, 8.95+/-0.05, and 9.25+/-0.05 yr with the respective distance of 957+/-152, 982+/-132, and 2554+/-387 pc for the clusters NGC 381, NGC 2360, and Be 68. A two-stage power law in the mass function (MF) slope is observed in the cluster NGC 381, however, we observe only a single MF slope in the clusters NGC 2360 and Be68. To study a possible spatial variation in the slope of MF we estimate slopes separately in the inner and the outer regions of these clusters and notice a steeper slope in outer region. The dynamic study of these clusters reveals deficiency of low-mass stars in their inner regions suggesting the mass segregation process in all these clusters. The relaxation times of 48.5, 78.9, and 87.6 Myr are obtained for the clusters NGC 381, NGC 2360, and Be 68, respectively which are well below to their respective ages. This suggests that all the clusters are dynamically relaxed.
- [11] arXiv:2004.01786 [pdf, other]
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Title: Molecular gas in CLASH brightest cluster galaxies at $z\sim0.2-0.9$Authors: G. Castignani, M. Pandey-Pommier, S. L. Hamer, F. Combes, P. Salomé, J. Freundlich, P. JablonkaComments: 15 pages, 8 figures, 4 tables, submitted to A&ASubjects: Astrophysics of Galaxies (astro-ph.GA); Cosmology and Nongalactic Astrophysics (astro-ph.CO)
Brightest cluster galaxies (BCGs) are excellent laboratories to study galaxy evolution in dense Mpc-scale environments. We have observed in CO(1-0), CO(2-1), CO(3-2), or CO(4-3), with the IRAM-30m, 18 BCGs at $z\sim0.2-0.9$ that are drawn from the CLASH survey. Our sample includes RX1532, which is our primary target, being among the BCGs with the highest star formation rate (SFR$\gtrsim100~M_\odot$/yr) in the CLASH sample. We unambiguously detected both CO(1-0) and CO(3-2) in RX1532, yielding a large reservoir of molecular gas, $M_{H_2}=(8.7\pm1.1)\times10^{10}~M_\odot$, and a high level of excitation $r_{31}=0.75\pm0.12$. A morphological analysis of the HST I-band image of RX1532 reveals the presence of clumpy substructures both within and outside the half-light radius $r_e=(11.6\pm0.3)$ kpc, similarly to those found independently both in ultraviolet and in H$_\alpha$ in previous work. We tentatively detected CO(1-0) or CO(2-1) in four other BCGs, with molecular gas reservoirs in the range $M_{H_2}=2\times10^{10-11} M_\odot$. For the remaining 13 BCGs we set robust upper limits of $M_{H_2}/M_\star\lesssim0.1$, which are among the lowest molecular gas to stellar mass ratios found for distant ellipticals and BCGs. By comparison with distant cluster galaxies observed in CO our study shows that RX1532 ($M_{H_2}/M_\star = 0.40\pm0.05$) belongs to the rare population of star forming and gas-rich BCGs in the distant universe. By using available X-ray based estimates of the central intra-cluster medium entropy, we show that the detection of large reservoirs of molecular gas $M_{H_2}\gtrsim10^{10}~M_\odot$ in distant BCGs is possible when the two conditions are met: i) high SFR and ii) low central entropy, which favors the condensation and the inflow of gas onto the BCGs themselves, similarly to what has been previously found for some local BCGs.
- [12] arXiv:2004.01795 [pdf, other]
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Title: On the contribution of quiet Sun magnetism to solar irradiance variations: Constraints on quiet Sun variability and grand minimum scenariosAuthors: M. RempelComments: 15 pages, 10 figures, accepted for publication in ApJSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
While the quiet Sun magnetic field shows only little variation with the solar cycle, long-term variations cannot be completely ruled out from first principles. We investigate the potential effect of quiet Sun magnetism on spectral solar irradiance through a series of small-scale dynamo simulations with zero vertical flux imbalance ($\langle B_z\rangle=0$) and varying levels of small-scale magnetic field strength, and one weak network case with an additional flux imbalance corresponding to a flux density of $\langle B_z\rangle=100$ G. From these setups we compute the dependence of the outgoing radiative energy flux on the mean vertical magnetic field strength in the photosphere at continuum optical depth $\tau=1$ ($\langle \vert B_z\vert\rangle_{\tau=1}$). We find that a quiet Sun setup with a mean vertical field strength of $\langle \vert B_z\vert\rangle_{\tau=1}=69$ G is about $0.6~\%$ brighter than a non-magnetic reference case. We find a linear dependence of the outgoing radiative energy flux on the mean field strength $\langle \vert B_z\vert\rangle_{\tau=1}$ with a relative slope of $1.4\cdot 10^{-4}$ G$^{-1}$. With this sensitivity, only a moderate change of the quiet Sun field strength by $10\%$ would lead to a total solar irradiance variation comparable to the observed solar cycle variation. While this does provide strong indirect constraints on possible quiet Sun variations during a regular solar cycle, it also emphasizes that potential variability over longer time scales could make a significant contribution to longer-term solar irradiance variations.
- [13] arXiv:2004.01796 [pdf, ps, other]
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Title: Broadband X-ray Spectral Study of Ultra-luminous X-ray Source M81 X--6Comments: Accepted for Publication in MNRAS, 6 Pages, 4 Figures, 1 TableSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
Ultra-luminous X-ray sources (ULXs) are a class of extra-galactic, point-like, off-nuclear X-ray sources with X-ray luminosity from $\sim 10^{39}$~erg s$^{-1}$ to $10^{41}$~erg s$^{-1}$. We investigated the temporal and broadband X-ray spectral properties of the ULX M81~X--6 using simultaneous \textit{Suzaku} and \textit{NuSTAR} observations. To understand the nature of the source, we searched for pulsating signals from the source using the \textit{NuSTAR} observation. However, we failed to identify any strong pulsating signals from the source. Alternatively, the broadband spectral modelling with accreting magnetic neutron star continuum model provides a statistically acceptable fit, and the inferred spectral parameters and X-ray colours are consistent with other pulsating ULXs. Thus, our analysis suggests that M81~X--6 is another candidate ULX pulsar.
- [14] arXiv:2004.01811 [pdf, other]
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Title: Panchromatic Properties of the Extreme FeII Emitter PHL 1092Comments: Accepted for publication at MNRASSubjects: Astrophysics of Galaxies (astro-ph.GA)
We present near-infrared spectroscopy of the NLS1 galaxy PHL1092 (z=0.394), the strongest FeII emitter ever reported, combined with optical and UV data. We modeled the continuum and the broad emission lines using a power-law plus a black body function and Lorentzian functions, respectively. The strength of the FeII emission was estimated using the latest FeII templates in the literature. We re-estimate the ratio between the FeII complex centered at 4570Ang and the broad component of H-Beta, R_FeII, obtaining a value of 2.58, nearly half of that previously reported (R_FeII=6.2), but still placing PHL1092 among extreme FeII emitters. The FWHM found for low ionization lines are very similar (FWHM~1200km/s), but significantly narrower than those of the Hydrogen lines (FWHM(H-Beta)~1900km/s). Our results suggest that the FeII emission in PHL1092 follows the same trend as in normal FeII emitters, with FeII being formed in the outer portion of the BLR and co-spatial with CaII, and OI, while H-Beta is formed closer to the central source. The flux ratio between the UV lines suggest high densities, log(n_H)~13.0 cm^{-3}, and a low ionization parameter, log(U)~-3.5. The flux excess found in the FeII bump at 9200Ang after the subtraction of the NIR FeII template and its comparison with optical FeII emission suggests that the above physical conditions optimize the efficiency of the ly-Alpha fluorescence process, which was found to be the main excitation mechanism in the FeII production. We discuss the role of PHL1092 in the Eigenvector 1 context.
- [15] arXiv:2004.01827 [pdf, ps, other]
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Title: Toward a Full MHD Jet Model of Spinning Black Holes--II: Kinematics and Application to the M87 JetComments: 15 pages, 9 figures, accepted by ApJSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
In this paper, we investigate the magnetohydrodynamical structure of a jet powered by a spinning black hole, where electromagnetic fields and fluid motion are governed by the Grad-Shafranov equation and the Bernoulli equation, respectively. Assuming steady and axisymmetric jet structure, the global solution is uniquely determined with prescribed plasma loading into the jet and the poloidal shape of the outmost magnetic field line. We apply this model to the jet in the center of nearby radio galaxy M87, and we find it can naturally explain the slow flow acceleration and the flow velocity stratification within $10^5$ gravitational radii from the central black hole. In particular, we find the extremal black hole spin is disfavored by the flow velocity measurements, if the plasma loading to the jet is dominated by the electron/positron pair production at the jet base.
- [16] arXiv:2004.01829 [pdf, other]
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Title: Extremely long convergence times in a 3D GCM simulation of the sub-Neptune Gliese 1214bComments: 36 pages, 17 figures, 2 tablesJournal-ref: The Astrophysical Journal, Volume 891, Issue 1, id.7 (2020)Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
We present gray gas general circulation model (GCM) simulations of the tidally locked mini-Neptune GJ 1214b. On timescales of 1,000-10,000 Earth days, our results are comparable to previous studies of the same planet, in the sense that they all exhibit two off-equatorial eastward jets. Over much longer integration times (50,000-250,000 Earth days) we find a significantly different circulation and observational features. The zonal-mean flow transitions from two off-equatorial jets to a single wide equatorial jet that has higher velocity and extends deeper. The hot spot location also shifts eastward over the integration time. Our results imply a convergence time far longer than the typical integration time used in previous studies. We demonstrate that this long convergence time is related to the long radiative timescale of the deep atmosphere and can be understood through a series of simple arguments. Our results indicate that particular attention must be paid to model convergence time in exoplanet GCM simulations, and that other results on the circulation of tidally locked exoplanets with thick atmospheres may need to be revisited.
- [17] arXiv:2004.01870 [pdf, ps, other]
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Title: The hazard from fragmenting cometsAuthors: W.M. NapierComments: 6 pages, 6 figuresJournal-ref: MNRAS 488, 1822-1827 (2019)Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Comet disintegration proceeds both through sublimation and discrete splitting events. The cross-sectional area of material ejected by a comet may, within days, become many times greater than that of the Earth, making encounters with such debris much more likely than collisions with the nucleus itself. The hierarchic fragmentation and sublimation of a large comet in a short period orbit may yield many hundreds of such short-lived clusters. We model this evolution with a view to assessing the probability of an encounter which might have significant terrestrial effects, through atmospheric dusting or multiple impacts. Such an encounter may have contributed to the large animal extinctions and sudden climatic cooling of 12,900 years ago, and the near-simultaneous collapse of civilisations around 2350 BC.
- [18] arXiv:2004.01892 [pdf, other]
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Title: Galaxy evolution studies in clusters: the case of Cl0024+1652 cluster galaxies at z$\sim$0.4Authors: Zeleke Beyoro-Amado (1,2,3) {E-mail: zbamado@gmail.com}, Mirjana Pović (1,4), Miguel Sánchez-Portal (5), Solomon Belay Tessema (1), Tilahun Getachew-Woreta (1,2,6), the GLACE team ((1) Ethiopian Space Science and Technology Institute (ESSTI), Addis Ababa, Ethiopia, (2) Addis Ababa University (AAU), Addis Ababa, Ethiopia, (3) Kotebe Metropolitan University, Addis Ababa, Ethiopia, (4) Instituto de Astrofísica de Andalucía (IAA-CSIC), Glorieta de la Astronomía, Granada, Spain, (5) Instituto de Radioastronomía Milimétrica, E-18012 Granada, Spain, (6) Bule Hora University, Bule Hora, Ethiopia)Comments: 5 pages, 3 figures; Proceedings paper of the IAU symposium 356 "Nuclear Activity in Galaxies Across Cosmic Time" (Ethiopia) accepted to be published under the Cambridge University Press, eds. M. Povic, P. Marziani, J. Masegosa, H. Netzer, S. H. Negu, and S. B. TessemaSubjects: Astrophysics of Galaxies (astro-ph.GA); Cosmology and Nongalactic Astrophysics (astro-ph.CO)
Studying the transformation of cluster galaxies contributes a lot to have a clear picture of evolution of the universe. Towards that we are studying different properties (morphology, star formation, AGN contribution and metallicity) of galaxies in clusters up to $z\sim1.0$ taking three different clusters: ZwCl0024+1652 at $z\sim0.4$, RXJ1257+4738 at $z\sim0.9$ and Virgo at $z\sim0.0038$. For ZwCl0024+1652 and RXJ1257+4738 clusters we used tunable filters data from GLACE survey taken with GTC 10.4 m telescope and other public data, while for Virgo we used public data. We did the morphological classification of 180 galaxies in ZwCl0024+1652 using galSVM, where 54\% and 46\% of galaxies were classified as early-type (ET) and late-type (LT) respectively. We did a comparison between the three clusters within the clustercentric distance of 1Mpc and found that ET proportion (decreasing with redshift) dominates over the LT (increasing with redshift) throughout. We finalized the data reduction for ZwCl0024+1652 cluster and identified 46 [OIII] and 73 H$\beta$ emission lines. For this cluster we have classified 22 emission line galaxies (ELGs) using BPT-NII diagnostic diagram resulting with 14 composite, 1 AGN and 7 star forming (SF) galaxies. We are using these results, together with the public data, for further analysis of the variations of properties in relation to redshift within $z<1.0$.
- [19] arXiv:2004.01914 [pdf, ps, other]
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Title: The ARTEMIS simulations: stellar haloes of Milky Way-mass galaxiesAuthors: Andreea S. Font, Ian G. McCarthy, Robert Poole-Mckenzie, Sam G. Stafford, Shaun T. Brown, Joop Schaye, Robert A. Crain, Tom Theuns, Matthieu SchallerComments: 22 pages, 12 figures, submitted to MNRASSubjects: Astrophysics of Galaxies (astro-ph.GA)
We introduce the ARTEMIS simulations, a new set of 42 zoomed-in, high-resolution (baryon particle mass of ~ 2x10^4 Msun/h), hydrodynamical simulations of galaxies residing in haloes of Milky Way mass, simulated with the EAGLE galaxy formation code with re-calibrated stellar feedback. In this study, we analyse the structure of stellar haloes, specifically the mass density, surface brightness, metallicity, colour and age radial profiles, finding generally very good agreement with recent observations of local galaxies. The stellar density profiles are well fitted by broken power laws, with inner slopes of ~ -3, outer slopes of ~ -4 and break radii that are typically ~ 20-40 kpc. The break radii generally mark the transition between in situ formation and accretion-driven formation of the halo. The metallicity, colour and age profiles show mild large-scale gradients, particularly when spherically-averaged or viewed along the major axes. Along the minor axes, however, the profiles are nearly flat, in agreement with observations. Overall, the structural properties can be understood by two factors: that in situ stars dominate the inner regions and that they reside in a spatially-flattened distribution that is aligned with the disc. Observations targeting both the major and minor axes of galaxies are thus required to obtain a complete picture of stellar haloes.
- [20] arXiv:2004.01933 [pdf, ps, other]
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Title: Extragalactic background light models and GeV-TeV observation of blazarsComments: 4 Figures, 4 Tables, Accepted for Publication in NRIAG JOURNAL OF ASTRONOMY AND GEOPHYSICS, Abstract shortenedSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
In this work, we use two different methods to determine the opacity of the TeV gamma-rays caused by the extragalactic background light (EBL) via e-e+ production due to photon-photon interaction. The first method, Model-Dependent Approach, uses various EBL models for estimating the opacity as a function of the redshift and energy of the TeV photons. The second method, Model-Independent Approach, relies on using the simultaneous observations of blazars in the MeV-GeV energy range from the Fermi-LAT and in the TeV band from the ground-based gamma-ray telescopes. We make the underline assumption that the extrapolation of the LAT spectrum of blazars to TeV energies is either a good estimate or an upper limit for the intrinsic TeV spectrum of a source. We apply this method on the simultaneous observations of a few blazars at different redshifts to demonstrate a comparative study of six prominent EBL models. Opacities of the TeV photons predicted by the model-independent approach are systematically larger than the ones estimated from the model-dependent method. Therefore, the gamma-ray observations of blazars can be used to set a strict upper limit on the opacity of the Universe to the TeV photons at a given redshift.
- [21] arXiv:2004.01960 [pdf, other]
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Title: Impact of intrinsic polarisation of Sgr A* historical flares on (polarisation) properties of their X-ray echoesComments: 7 pages, 4 figures, submitted to MNRASSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics of Galaxies (astro-ph.GA)
Reflection of X-ray emission on molecular clouds in the inner $\sim$ 100 pc of our Galaxy reveals that, despite being extremely quiet at the moment, our supermassive black hole Sgr A* should have experienced bright flares of X-ray emission in the recent past. Thanks to the improving characterisation of the reflection signal, we are able to infer parameters of the most recent flare(s) (age, duration and luminosity) and relative line-of-sight disposition of the brightest individual molecular complexes. We show that combining these data with measurements of polarisation in the reflected X-ray continuum will not only justify Sgr A* as the primary source but also allow deriving intrinsic polarisation properties of the flare emission. This will help to identify radiation mechanisms and underlying astrophysical phenomena behind them. For the currently brightest reflecting molecular complex, Sgr A, the required level of sensitivity might be already accessible with upcoming X-ray polarimeters.
- [22] arXiv:2004.01982 [pdf]
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Title: Thermal formation of ammonium carbamate on the surface of laboratory analogues of carbonaceous grains in protostellar envelopes and planet-forming disksSubjects: Astrophysics of Galaxies (astro-ph.GA)
The catalytic role of dust grain surfaces in the thermal reaction CO2 + 2NH3 $\rightarrow$ NH4+NH2COO was recently demonstrated by our group. The rate coefficients for the reaction at 80 K on the surface of nanometre-sized carbon and silicate grains were measured to be up to three times higher compared to the reaction rate coefficients measured on KBr. In this study, the reaction was performed on carbon grains and on KBr in the extended temperature range of 50 - 80 K and with the addition of water ice. The reaction activation energy was found to be about 3 times lower on grains compared to the corresponding ice layer on KBr. Thus, the catalytic role of the dust grain surface in the studied reaction can be related to a reduction of the reaction barrier. Addition of water to NH3:CO2 ice on grains slowed the reaction down. At the H2O:CO2 ratio of 5:1, the reaction was not detected on the experimental timescale. This result calls into question the thermal formation of ammonium carbamate in dense molecular clouds and outer regions of protostellar and protoplanetary environments with dominating water ice mantle chemistry. However, it can still happen in inner regions of protostellar and protoplanetary environments in crystalline ices.
- [23] arXiv:2004.01988 [pdf, other]
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Title: BLR size in Realistic FRADO Model: The role of shielding effectComments: 12 pages, 3 figures, accepted for publication in Journal of Frontiers in Astronomy and Space SciencesSubjects: Astrophysics of Galaxies (astro-ph.GA); High Energy Astrophysical Phenomena (astro-ph.HE)
The effective size of Broad Line Region (BLR), so-called the BLR radius, in galaxies with active galactic nuclei (AGN) scales with the source luminosity. Therefore by determining this location either observationally through reverberation mapping or theoretically, one can use AGNs as an interesting laboratory to test cosmological models. In this article we focus on the theoretical side of BLR based on the Failed Radiatively Accelerated Dusty Outflow (FRADO) model. By simulating the dynamics of matter in BLR through a realistic model of radiation of accretion disk (AD) including the shielding effect, as well as incorporating the proper values of dust opacities, we investigate how the radial extension and geometrical height of the BLR depends on the Eddington ratio [and blackhole mass], and modeling of shielding effect. We show that assuming a range of Eddington ratios and shielding we are able to explain the measured time-delays in a sample of reverberation-measured AGNs.
- [24] arXiv:2004.02033 [pdf, ps, other]
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Title: Interstellar Comet 2I/Borisov exhibits a structure similar to native Solar System cometsAuthors: F. Manzini (1), V. Oldani (1), P. Ochner (2,3), L. R. Bedin (3). ((1) Stazione Astronomica di Sozzago, Cascina Guascona, (2) INAF-Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, (3) Department of Physics and Astronomy-University of Padova)Comments: 5 pages, 6 figures (low resolution). Full-resolution figures and bonus material at this url this https URL Accepted for publication in MNRAS Letters on 2020 April 1st (not a joke ;)Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
We processed images taken with the Hubble Space Telescope (HST) to investigate any morphological features in the inner coma suggestive of a peculiar activity on the nucleus of the interstellar comet 2I/Borisov. The coma shows an evident elongation, in the position angle (PA) ~0-180d direction, which appears related to the presence of a jet originating from a single active source on the nucleus. A counterpart of this jet directed towards PA ~10d was detected through analysis of the changes of the inner coma morphology on HST images taken in different dates and processed with different filters. These findings indicate that the nucleus is probably rotating with a spin axis projected near the plane of the sky and oriented at PA ~100d-280d, and that the active source is lying in a near-equatorial position. Subsequent observations of HST allowed us to determine the direction of the spin axis at RA=17h20m+/-15d and Dec = -35d+\-10d.
- [25] arXiv:2004.02039 [pdf, ps, other]
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Title: A Comparison of Properties of Quasars with and without Rapid Broad Absorption Line VariabilityComments: 22 pagesSubjects: Astrophysics of Galaxies (astro-ph.GA)
We investigate the correlation between rest-frame UV flux variability of broad absorption line (BAL) quasars and their variability in BAL equivalent widths (EWs) in a various timescale from $<10$~days to a few years in the quasar rest-frame. We use the data sets of BAL EWs taken by the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project and photometric data taken by the intermediate Palomar Transient Factory (iPTF) in $g$ and $R$-bands and the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) in $grizy$ bands. Our results are summarized as below; (1) the distributions of flux variability versus BAL variability show weak, moderate, or a strong positive correlation, (2) there is no significant difference in flux variability amplitudes between BAL quasar with significant short timescale EW variability (called class S1) and without (class S2), (3) in all time scales considered in this paper, the class S1 quasars show systematically larger BAL variability amplitudes than those of the class S2 quasars, and (4) there are possible correlations between BAL variability and physical parameters of the quasars such as black hole masses (moderate positive), Eddington ratios, and accretion disk temperature (strong negative) in the class S2 quasars. These results indicate that the BAL variability requires changing in the ionizing continuum and an ancillary mechanism such as variability in X-ray shielding gas located at the innermost region of an accretion disk.
- [26] arXiv:2004.02045 [pdf, other]
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Title: Presupernova neutrinos: directional sensitivity and prospects for progenitor identificationComments: LaTeX, 16 pages, 9 figures, 7 tablesSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph); Nuclear Theory (nucl-th)
We explore the potential of current and future liquid scintillator neutrino detectors of O(10) kt mass to localize a presupernova neutrino signal in the sky. In the hours preceding the core collapse of a nearby star (at distance D < 1 kpc), tens to hundreds of inverse beta decay events will be recorded, and their reconstructed topology in the detector can be used to estimate the direction to the star. Although the directionality of inverse beta decay is weak (~8% forward-backward asymmetry for currently available liquid scintillators), we find that for a fiducial signal of 200 events (which is realistic for Betelgeuse), a positional error of ~60 degrees can be achieved, resulting in the possibility to narrow the list of potential stellar candidates to less than ten, typically. For a configuration with improved forward-backward asymmetry (~40%, as expected for a lithium-loaded liquid scintillator), the angular sensitivity improves to ~15 degrees, and - when a distance upper limit is obtained from the overall event rate - it is in principle possible to uniquely identify the progenitor star. Any localization information accompanying an early supernova alert will be useful to multi-messenger observations and to particle physics tests using collapsing stars.
- [27] arXiv:2004.02054 [pdf]
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Title: Interarm islands in the Milky Way -- the one near the Cygnus spiral armAuthors: Jacques P ValléeComments: 26 pages; 4 figures; 3 tables; 71 references; 1 equation. Accepted for publicationSubjects: Astrophysics of Galaxies (astro-ph.GA)
This study extends to the structure of the Galaxy. Our main goal is to focus on the first spiral arm beyond the Perseus arm, often called the Cygnus arm or the Outer Norma arm, by appraising the distributions of the masers near the Cygnus arm. The method is to employ masers whose trigonometric distances were measured with accuracy. The maser data come from published literature, having been obtained via the existing networks (US VLBA, the Japanese VERA, the European VLBI, and the Australian LBA). The new results for Cygnus are split in two groups: those located near a recent CO fitted global model spiral arm, and those congregating within an interarm island located halfway between the Perseus arm and the Cygnus arm. Next, we compare this island with other similar interarm objects near other spiral arms. Thus we delineate an interarm island (6 x 2 kpc) located between the two long spiral arms (Cygnus and Perseus arms); this is reminiscent of the small Local Orion arm (4 x 2 kpc) found earlier between the Perseus and Sagittarius arms, and of the old Loop (2 x 0.5 kpc) found earlier between the Sagittarius and Scutum arms. Various arm models are compared, based on observational data (masers, HII regions, HI gas, young stars, CO gas).
- [28] arXiv:2004.02055 [pdf, other]
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Title: On the character of turbulence in self-consistent models of core-collapse supernovaeAuthors: Jordi Casanova, Eirik Endeve, Eric J. Lentz, O. E. Bronson Messer, W. Raphael Hix, J. Austin Harris, Stephen W. BruennComments: Accepted Special Issue Article in Physica ScriptaSubjects: Solar and Stellar Astrophysics (astro-ph.SR); High Energy Astrophysical Phenomena (astro-ph.HE)
Neutrino-driven convection plays a crucial role in the development of core-collapse supernova (CCSN) explosions. However, the complex mechanism that triggers the shock revival and the subsequent explosion has remained inscrutable for many decades. Multidimensional simulations suggest that the growth of fluid instabilities and the development of turbulent convection will determine the morphology of the explosion. We have performed 3D simulations using spherical-polar coordinates covering a reduced angular extent (90 degree computational domain), and with angular resolutions of 2 degrees, 1 degree, 1/2 degree, and 1/4 degree, to study the development of turbulence in core-collapse supernova explosions on a time scale of order 100 ms. We have employed the multi-physics Chimera code that includes detailed nuclear physics and spectral neutrino transport. Coarse resolution models do not develop an inertial range, presumably due to the bottleneck effect, such that the energy is prevented from cascading down to small scales and tends to accumulate at large scales. High-resolution models instead, start to recover the k^{-5/3} scaling of Kolmogorov's theory. Stochasticity and few simulation samples limit our ability to predict the development of explosions. Over the simulated time period, our models show no clear trend in improving (or diminishing) conditions for explosion as the angular resolution is increased. However, we find that turbulence provides an effective pressure behind the shock (approx. 40 - 50 % of the thermal pressure), which can contribute to the shock revival and be conducive for the development of the explosion. Finally, we show that the turbulent energy power spectrum of reduced angular extent and full 4 pi models are consistent, thus indicating that a 90 degree computational domain is an adequate configuration to study the character of turbulence in CCSNe.
- [29] arXiv:2004.02079 [pdf, other]
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Title: Luminosity-duration relations and luminosity functions of repeating and non-repeating fast radio burstsAuthors: Tetsuya Hashimoto, Tomotsugu Goto, Ting-Wen Wang, Seong Jin Kim, Simon C.-C. Ho, Alvina Y. L. On, Ting-Yi Lu, Daryl Joe D. SantosComments: Accepted by MNRAS. For a summary of the paper, please see below. this https URLSubjects: Astrophysics of Galaxies (astro-ph.GA); High Energy Astrophysical Phenomena (astro-ph.HE)
Fast radio bursts (FRBs) are mysterious radio bursts with a time scale of approximately milliseconds. Two populations of FRB, namely repeating and non-repeating FRBs, are observationally identified. However, the differences between these two and their origins are still cloaked in mystery. Here we show the time-integrated luminosity-duration ($L_{\nu}$-$w_{\rm int,rest}$) relations and luminosity functions (LFs) of repeating and non-repeating FRBs in the FRB Catalogue project. These two populations are obviously separated in the $L_{\nu}$-$w_{\rm int,rest}$ plane with distinct LFs, i.e., repeating FRBs have relatively fainter $L_{\nu}$ and longer $w_{\rm int,rest}$ with a much lower LF. In contrast with non-repeating FRBs, repeating FRBs do not show any clear correlation between $L_{\nu}$ and $w_{\rm int,rest}$. These results suggest essentially different physical origins of the two. The faint ends of the LFs of repeating and non-repeating FRBs are higher than volumetric occurrence rates of neutron-star mergers and accretion-induced collapse (AIC) of white dwarfs, and are consistent with those of soft gamma-ray repeaters (SGRs), type Ia supernovae, magnetars, and white-dwarf mergers. This indicates two possibilities: either (i) faint non-repeating FRBs originate in neutron-star mergers or AIC and are actually repeating during the lifetime of the progenitor, or (ii) faint non-repeating FRBs originate in any of SGRs, type Ia supernovae, magnetars, and white-dwarf mergers. The bright ends of LFs of repeating and non-repeating FRBs are lower than any candidates of progenitors, suggesting that bright FRBs are produced from a very small fraction of the progenitors regardless of the repetition. Otherwise, they might originate in unknown progenitors.
- [30] arXiv:2004.02091 [pdf, ps, other]
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Title: Simulations of the Early Post-Bounce Phase of Core-Collapse Supernovae in Three-Dimensional Space with Full Boltzmann Neutrino TransportAuthors: Wakana Iwakami, Hirotada Okawa, Hiroki Nagakura, Akira Harada, Shun Furusawa, Kosuke Sumiyoshi, Hideo Matsufuru, Shoichi YamadaComments: 24 pages, 17 figures, submitted to ApJSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
We report on the core-collapse supernova simulation we conducted for a 11.2M progenitor model in three-dimensional space up to 20 ms after bounce, using a radiation hydrodynamics code with full Boltzmann neutrino transport. We solve the six-dimensional Boltzmann equations for three neutrino species and the three-dimensional compressible Euler equations with Furusawa and Togashi's nuclear equation of state. We focus on the prompt convection at ~10 ms after bounce and investigate how neutrinos are transported in the convective matter. We apply a new analysis based on the eigenvalues and eigenvectors of the Eddington tensor and make a comparison between the Boltzmann transport results and the M1 closure approximation in the transition regime between the optically thick and thin limits. We visualize the eigenvalues and eigenvectors using an ellipsoid, in which each principal axis is parallel to one of the eigenvectors and has a length proportional to the corresponding eigenvalue. This approach enables us to understand the difference between the Eddington tensor derived directly from the Boltzmann simulation and the one given by the M1 prescription from a new perspective. We find that the longest principal axis of the ellipsoid is almost always nearly parallel to the energy flux in the M1 closure approximation whereas in the Boltzmann simulation it becomes perpendicular in some transition regions, where the mean free path is ~0.1 times the radius. In three spatial dimensions, the convective motions make it difficult to predict where this happens and possibly improves the closure relation there.
- [31] arXiv:2004.02155 [pdf, other]
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Title: Hints of a Local Matter Underdensity or Modified Gravity in the Low $z$ Pantheon dataComments: 16 pages, 12 figures, 2 Tables. The mathematica files for the production of the figures can be downloaded from this url this https URLSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)
A redshift tomography of the Pantheon type Ia supernovae (SnIa) data focusing on the best fit value of the absolute magnitude $M$ and/or Hubble constant $H_0$ in the context of $\Lambda$CDM indicates a local variation ($z\lesssim 0.2$) at $2\sigma$ level, with respect to the best fit of the full dataset. If this variation is physical, it can be interpreted either as a locally higher value of $H_0$, corresponding to a local matter underdensity $\delta \rho_0/\rho_0 \simeq -0.10 \pm 0.04$ or as a time variation of Newton's constant which implies an evolving Chandrasekhar mass and thus an evolving absolute magnitude $M$ of SnIa. The local void scenario would predict an anisotropy in the best fit value of $H_0$ (and/or $M$) since it is unlikely that we are located at the center of a local spherical underdensity. Using a hemisphere comparison method we find an anisotropy level consistent with simulated isotropic datasets. We show however, that the anisotropic sky distribution of the Pantheon SnIa data induces a preferred range of directions even in simulated Pantheon data obtained in the context of isotropic $\Lambda$CDM. We thus construct a more isotropically distributed subset of the Pantheon SnIa and show that the preferred range of directions disappears. Using this subset we again find no evidence for anisotropy using either the hemisphere comparison method or the dipole fit method. In the context of the modified gravity scenario, we allow for an evolving normalized Newton's constant consistent with General Relativity (GR) at early and late times $\mu(z)=1+g_a z^2/(1+z)^2-g_a z^4/(1+z)^4$ and fit for $g_a$ assuming $L\sim G_{\rm{eff}}^b$. For $b=-3/2$ indicated by previous studies we find $g_a=-0.47 \pm 0.36$ which is more than $1.5\sigma$ away from the GR value of $g_a=0$. This weak hint for weaker gravity at low $z$ is consistent with similar evidence from growth and weak lensing data.
- [32] arXiv:2004.02204 [pdf, other]
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Title: Star Formation Enhancement in Barred Disk Galaxies in Interacting Galaxy ClustersComments: 12 pages, 8 figures, 1 table, accepted for publication in the ApJSubjects: Astrophysics of Galaxies (astro-ph.GA)
A recent study shows that bars can be induced via interaction of galaxy clusters, but it has been unclear if the bar formation by the interaction between clusters is related to the enhancement of star formation. We study galaxies in 105 galaxy clusters at $0.015<z<0.060$ detected from Sloan Digital Sky Survey data, in order to examine whether the fraction of star-forming galaxies ($f_\mathrm{sf}$) in 16 interacting clusters is enhanced compared with that of the other non-interacting clusters and to investigate the possible connection between the $f_\mathrm{sf}$ enhancement and the bar formation in interacting clusters. We find that $f_\mathrm{sf}$ is moderately higher ($\sim20\%$) in interacting clusters than in non-interacting clusters and that the enhancement of star formation in interacting clusters occurs only in moderate-mass disk-dominated galaxies ($10^{10.0} \le M_\mathrm{star}/M_{\odot} < 10^{10.4}$ and the bulge-to-total light ratio is $\le0.5$). We also find that the enhancement of $f_\mathrm{sf}$ in moderate-mass disk-dominated galaxies in interacting clusters is mostly due to the increase of the number of barred galaxies. Our result suggests that the cluster-cluster interaction can simultaneously induce bars and star formation in disk galaxies.
- [33] arXiv:2004.02225 [pdf]
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Title: Simple $Δ$V Approximation for Optimization of Debris-to-Debris TransfersSubjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Earth and Planetary Astrophysics (astro-ph.EP); Optimization and Control (math.OC)
A method for the rapid estimation of transfer costs for the removal of debris in low Earth orbit is proposed. Debris objects among a population with similar inclination values are considered. The proposed approximate analysis can provide estimations of actual Deltav between any debris object pair as a function of time; these estimations allow for the rapid evaluation of the costs of large sequences of targets to be removed. The effect of Earth's oblateness perturbation (J2) is exploited to reduce transfer costs. The debris removal problem of the 9th edition of the Global Trajectory Optimization Competition is used to evaluate the estimation accuracy; Deltav estimations of the transfers between objects pairs are verified by comparing them with the GTOC9 solution proposed by the winning team from JPL. The comparison of the results demonstrates the very good accuracy of the simple approximation. Key words: Space debris; approximation; trajectory optimization; J2 perturbation
- [34] arXiv:2004.02237 [pdf]
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Title: SADAS: an integrated software system for the data of the SuperAGILE experimentComments: 5 pages, 4 figuresJournal-ref: Francesco Lazzarotto and Ettore Del Monte, "SADAS: an integrated software system for the data of the SuperAGILE experiment", in Proceedings of ADA III conference, (S. Agata sui due Golfi, Naples), 2004, DOI:10.14236/ewic/ADA-III2004.11Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Software Engineering (cs.SE)
SuperAGILE (SA) is a detection system on board of the AGILE satellite (Astro-rivelatore Gamma a Immagini LEggero), a Gamma-ray astronomy mission approved by the Italian Space Agency (ASI) as first project for the Program for Small Scientific Missions, with launch planned in the second part of 2005. The developing and testing of the instrument took a big effort in software building and applications, we realized an integrated system to handle and to analyse measurement data since prototype tests until flight observations. The software system was created with an Object Oriented software design approach, and this permits to employ suitable libraries developed by other research teams and the integration of applications developed during our past work. This method allowed us to apply our schemas and written code on several prototypes, to share the work among different developers with the help of standard modeling instruments such as UML schemas. We also used SQL-based database techniques to access large amounts of data stored in the archives, this will improve the scientific return from space observations. All this has allowed our team to minimize the cost of developing in terms of man-power and resources, to dispone of a flexible system to face future needs of the mission and to invest it on other experiments.
- [35] arXiv:2004.02250 [pdf, other]
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Title: Study of AGN contribution on morphological parameters of their host galaxiesAuthors: Tilahun Getachew-Woreta, Mirjana Pović, Josefa Masegosa, Jaime Perea, Zeleke Beyoro-Amado, Isabel Marquez PerezComments: Proceedings paper of the IAU symposium "Nuclear Activity in Galaxies Across Cosmic Time" (Ethiopia) accepted to be published under the Cambridge University Press, eds. M. Povi\'c, P. Marziani, J. Masegosa, H. Netzer, S. H. Negu, and S. B. TessemaSubjects: Astrophysics of Galaxies (astro-ph.GA)
We tested how the AGN contribution (5% - 75% of the total flux) may affect different morphological parameters commonly used in galaxy classification. We carried out all analysis at $z$,$sim$,0 and at higher redshifts that correspond to the COSMOS field. Using a local training sample of $>$,2000 visually classified galaxies, we carried out all measurements with and without the central source and quantified how the contribution of a bright nuclear point source could affect different morphological parameters, such as: Abraham and Concelice-Bershady indices, Gini, Asymmetry, $M20$ moment of light, and Smoothness. We found that concentration indexes are less sensitive to both redshift and brightness in comparison to the other parameters. We also found that all parameters change significantly with AGN contribution. At $z$$\sim$0, up to a 10% of AGN contribution the morphological classification will not be significantly affect, but for $\ge$25% of AGN contribution late-type spirals follow the range of parameters of elliptical galaxies and can therefore be misclassified early types.
- [36] arXiv:2004.02259 [pdf, other]
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Title: Exomoon indicators in high-precision transit light curvesComments: 13 pages, 9 figures, 1 tableSubjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
While the solar system contains about 20 times more moons than planets, no moon has been confirmed around any of the thousands of extrasolar planets known so far. Tools for an uncomplicated identification of the most promising exomoon candidates could be beneficial to streamline follow-up studies.} Here we study three exomoon indicators that emerge if well-established planet-only models are fitted to a planet-moon transit light curve: transit timing variations (TTVs), transit duration variations (TDVs), and apparent planetary transit radius variations (TRVs). We re-evaluate under realistic conditions the previously proposed exomoon signatures in the TTV and TDV series. We simulate light curves of a transiting exoplanet with a single moon. These model light curves are then fitted with a planet-only transit model, pretending there were no moon, and we explore the resulting TTV, TDV, and TRV series for evidence of the moon. The previously described ellipse in the TTV-TDV diagram of an exoplanet with a moon emerges only for high-density moons. Low-density moons distort the sinusoidal shapes of the TTV and the TDV series due to their photometric contribution to the combined planet-moon transit. Sufficiently large moons can produce periodic apparent TRVs of their host planets that could be observable. We find that Kepler and PLATO have similar performances in detecting the exomoon-induced TRV effect around simulated bright ($m_V=8$) stars. These stars, however, are rare in the Kepler sample but will be abundant in the PLATO sample. Moreover, PLATO's higher cadence yields a stronger TTV signal. The periodogram of the sequence of transit radius measurements can indicate the presence of a moon. The TTV and TDV series of exoplanets with moons can be more complex than previously assumed. We propose that TRVs could be a more promising means to identify exomoons in large exoplanet surveys.
- [37] arXiv:2004.02305 [pdf, ps, other]
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Title: Accretion and jets in a low luminosity AGN: the nucleus of NGC 1052Comments: Accepted in A&A. 17 pages, 5 figuresSubjects: Astrophysics of Galaxies (astro-ph.GA); High Energy Astrophysical Phenomena (astro-ph.HE)
We aim to determine the properties of the central region of NGC 1052 using X-ray and radio data. NGC 1052 (z=0.005) has been investigated for decades in different energy bands and shows radio lobes and a low luminosity active galactic nucleus (LLAGN). We use X-ray images from Chandra and radio images from Very Large Array (VLA) to explore the morphology of the central area. We also study the spectra of the nucleus and the surrounding region using observations from Chandra and XMM-Newton. We find diffuse soft X-ray radiation and hotspots along the radio lobes. The spectrum of the circum-nuclear region is well described by a thermal plasma (T~0.6 keV) and a power law with photon index Gamma~2.3. The nucleus shows a hard power law (Gamma~1.4) modified by complex absorption. A narrow iron K-alpha line is also clearly detected in all observations, but there is no evidence for relativistic reflection. The extended emission is consistent with originating from extended jets and from jet-triggered shocks in the surrounding medium. The hard power-law emission from the nucleus and the lack of relativistic reflection supports the scenario of inefficient accretion in an Advection Dominated Accretion Flow (ADAF).
- [38] arXiv:2004.02341 [pdf, other]
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Title: The tachocline revisitedAuthors: Pascale GaraudComments: Invited review for the meeting Dynamics of the Sun and Stars: Honoring the Life and Work of Michael J. Thompson (Boulder, Colorado, 24-26 September 2019)Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Fluid Dynamics (physics.flu-dyn)
The solar tachocline is a shear layer located at the base of the solar convection zone. The horizontal shear in the tachocline is likely turbulent, and it is often assumed that this turbulence would be strongly anisotropic as a result of the local stratification. What role this turbulence plays in the tachocline dynamics, however, remains to be determined. In particular, it is not clear whether it would result in a turbulent eddy diffusivity, or anti-diffusivity, or something else entirely. In this paper, we present the first direct numerical simulations of turbulence in horizontal shear flows at low Prandtl number, in an idealized model that ignores rotation and magnetic fields. We find that several regimes exist, depending on the relative importance of the stratification, viscosity and thermal diffusivity. Our results suggest that the tachocline is in the stratified turbulence regime, which has very specific properties controlled by a balance between buoyancy, inertia, and thermal diffusion.
- [39] arXiv:2004.02343 [pdf, other]
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Title: Precision angular diameters for 16 southern stars with VLTI/PIONIERComments: Published in MNRAS, 22 pages, 7 figuresJournal-ref: Monthly Notices of the Royal Astronomical Society, Volume 493, Issue 2, April 2020, Pages 2377-2394Subjects: Solar and Stellar Astrophysics (astro-ph.SR)
In the current era of Gaia and large, high signal to noise stellar spectroscopic surveys, there is an unmet need for a reliable library of fundamentally calibrated stellar effective temperatures based on accurate stellar diameters. Here we present a set of precision diameters and temperatures for a sample of 6 dwarf, 5 sub-giant, and 5 giant stars observed with the PIONIER beam combiner at the VLTI. Science targets were observed in at least two sequences with five unique calibration stars each for accurate visibility calibration and to reduce the impact of bad calibrators. We use the standard PIONIER data reduction pipeline, but bootstrap over interferograms, in addition to employing a Monte-Carlo approach to account for correlated errors by sampling stellar parameters, limb darkening coefficients, and fluxes, as well as predicted calibrator angular diameters. The resulting diameters were then combined with bolometric fluxes derived from broadband Hipparcos-Tycho photometry and MARCS model bolometric corrections, plus parallaxes from Gaia to produce effective temperatures, physical radii, and luminosities for each star observed. Our stars have mean angular diameter and temperatures uncertainties of 0.8% and 0.9% respectively, with our sample including diameters for 10 stars with no pre-existing interferometric measurements. The remaining stars are consistent with previous measurements, with the exception of a single star which we observe here with PIONIER at both higher resolution and greater sensitivity than was achieved in earlier work.
- [40] arXiv:2004.02364 [pdf, other]
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Title: Formation of massive stars under protostellar radiation feedback: Very metal-poor starsAuthors: Hajime Fukushima, Takashi Hosokawa, Gen Chiaki, Kazuyuki Omukai, Naoki Yoshida, Rolf KuiperComments: 17 pages, 11 figures, submitted to MNRASSubjects: Astrophysics of Galaxies (astro-ph.GA); Solar and Stellar Astrophysics (astro-ph.SR)
We study the formation of very metal-poor stars under protostellar radiative feedback effect. We use cosmological simulations to identify low-mass dark matter halos and star-forming gas clouds within them. We then follow protostar formation and the subsequent long-term mass accretion phase of over one million years using two-dimensional radiation-hydrodynamics simulations. We show that the critical physical process that sets the final mass is formation and expansion of a bipolar HII region. The process is similar to the formation of massive primordial stars, but radiation pressure exerted on dust grains also contributes to halting the accretion flow in the low-metallicity case. We find that the net feedback effect in the case with metallicity $Z = 10^{-2}~Z_{\odot}$ is stronger than in the case with $Z \sim 1~Z_{\odot}$. With decreasing metallicity, the radiation pressure effect becomes weaker, but photoionization heating of the circumstellar gas is more efficient owing to the reduced dust attenuation. In the case with $Z = 10^{-2}~Z_{\odot}$, the central star grows as massive as 200 solar-masses, similarly to the case of primordial star formation. We conclude that metal-poor stars with a few hundred solar masses can be formed by gas accretion despite the strong radiative feedback.
- [41] arXiv:2004.02408 [pdf, ps, other]
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Title: Accretion Flow Properties of XTE J1118+480 During Its 2005 OutburstComments: 12 Pages, 3 Figures, 2 Tables, Accepted for publication in RAASubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
We study spectral and temporal properties of Galactic short orbital period transient black hole XTE J1118+480 during its 2005 outburst using archival data of RXTE PCA and HEXTE instruments in the combined energy range of $3-100$ keV. Spectral analysis with the physical two-component advective flow (TCAF) model allows us to understand the accretion flow properties of the source. We found that this outburst of XTE J1118+480 is an unconventional outburst as the source was only in the hard state (HS). Our spectral analysis suggests that during the entire outburst, the source was highly dominated by the low angular momentum sub-Keplerian halo rate. Since the source was active in radio throughout the outburst, we make an effort to estimate X-ray contribution of jets in total observed X-ray emissions from the spectral analysis with the TCAF model. The total X-ray intensity shows a similar nature of evolution as of radio and jet X-ray fluxes. This allowed us to define this `outburst' also as a jet dominated `outburst'. Total X-ray flux also found to subside when jet activity disappears. Our detailed spectral analysis also showed that although the source was only in the HS during the outburst, in the late declining phase spectrum became slightly softer due to the slow rise in the Keplerian disk rate.
- [42] arXiv:2004.02436 [pdf, ps, other]
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Title: Ultradense Gases beyond Dusty Torus in a Partially Obscured QuasarSubjects: Astrophysics of Galaxies (astro-ph.GA)
The co-evolution between black holes and galaxies suggests that feedback of active galactic nuclei influence host galaxies through ejecting radiative and kinetic energies to surroundings. Larger scale outflow in local universe are frequently observed by spatially resolved spectroscopy, while smaller scale outflow cannot be directly resolved by current observations. At the scale of the dusty torus, radiative and kinetic energies ejected from the central active nucleus interact with the materials. However, observations of such outflow are rarely reported due to the lack detection of unambiguously gas emission. Here we report the detection of clear and rich emission lines origin from the scale of dusty tours in an partially obscured quasar. The lines share a common intermediate width with full width at half maximum about 1900 \kmps\ and are shown in two systems: a major system is unshifted and a minor system has a blue-shifts of about 2600 \kmps. The line intensity ratios, combining photo-ionization simulations, indicates an ultradense line-emitting region with the density as high as $\sim$ $10^{13}~\rm cm^{-3}$. We interpret this as the lines being excited by a shock induced by the high-density and high-temperature gases at the scale of dusty torus, rather than photo-ionized by the central accretion disk. We speculate that the outflow, launched from the accretion disk, collides onto the inner wall of the dusty torus and shock-heat the gases to cause the major emission lines. The outflowing gases may also collide onto surrounding isolated clouds, and give rise to blue-shifted minor emission lines.
- [43] arXiv:2004.02447 [pdf, other]
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Title: Characterization of the June epsilon Ophiuchids meteoroid stream and the comet 300P/CatalinaSubjects: Earth and Planetary Astrophysics (astro-ph.EP)
Prior to 2019, the June epsilon Ophiuchids (JEO) were known as a minor unconfirmed meteor shower with activity that was considered typically moderate for bright fireballs. An unexpected bout of enhanced activity was observed in June 2019, which even raised the possibility that it was linked to the impact of the small asteroid 2019 MO near Puerto Rico. Early reports also point out the similarity of the shower to the orbit of the comet 300P/Catalina. We aim to analyze the orbits, emission spectra, and material strengths of JEO meteoroids to provide a characterization of this stream, identify its parent object, and evaluate its link to the impacting asteroid 2019 MO. Our analysis is based on a sample of 22 JEO meteor orbits and four emission spectra observed by the AMOS network at the Canary Islands and in Chile. The link to potential parent objects was evaluated using a combination of orbital-similarity D-criteria and backwards integration of the orbit of comet 300P and the JEO stream. We confirm the reports of an unexpected swarm of meteoroids originating in the JEO stream. JEO meteoroids have low material strengths characteristic for fragile cometary bodies, and they exhibit signs of a porous structure. The emission spectra reveal slightly increased iron content compared to all other measured cometary streams, but they are generally consistent with a primitive chondritic composition. Further dynamical analysis suggests that the JEO stream is likely to originate from comet 300P/Catalina and that it was formed within the last 1000 years. Over longer timescales, the meteoroids in the stream move to chaotic orbits due to the turbulent orbital evolution of the comet. Our results also suggest that the impact of the small asteroid 2019 MO on June 22 was not connected to the JEO activity.
- [44] arXiv:2004.02486 [pdf, ps, other]
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Title: New molecular species at redshift z=0.89Comments: Accepted for publication in A&ASubjects: Astrophysics of Galaxies (astro-ph.GA)
We present the first detections of CH3SH, C3H+, C3N, HCOOH, CH2CHCN, and H2CN in an extragalactic source. Namely the spiral arm of a galaxy located at z=0.89 on the line of sight to the radio-loud quasar PKS 1830-211. OCS, SO2, and NH2CN were also detected, raising the total number of molecular species identified in that early time galaxy to 54, not counting isotopologues. The detections were made in absorption against the SW quasar image, at 2 kpc from the galaxy centre, over the course of a Q band spectral line survey made with the Yebes 40 m telescope (rest-frame frequencies: 58.7-93.5 GHz). We derived the rotational temperatures and column densities of those species, which are found to be subthermally excited. The molecular abundances, and in particular the large abundances of C3H+ and of several previously reported cations, are characteristic of diffuse or translucent clouds with enhanced UV radiation or strong shocks.
- [45] arXiv:2004.02496 [pdf, other]
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Title: Formation of secondary atmospheres on terrestrial planets by late disk accretionComments: Paper accepted and now published in Nature Astronomy. See the published version here: this https URLSubjects: Earth and Planetary Astrophysics (astro-ph.EP)
Recently, gas disks have been discovered around main sequence stars well beyond the usual protoplanetary disk lifetimes (i.e., > 10 Myrs), when planets have already formed. These gas disks, mainly composed of CO, carbon, and oxygen seem to be ubiquitous in systems with planetesimal belts (similar to our Kuiper belt), and can last for hundreds of millions of years. Planets orbiting in these gas disks will accrete a large quantity of gas that will transform their primordial atmospheres into new secondary atmospheres with compositions similar to that of the parent gas disk. Here, we quantify how large a secondary atmosphere can be created for a variety of observed gas disks and for a wide range of planet types. We find that gas accretion in this late phase is very significant and an Earth's atmospheric mass of gas is readily accreted on terrestrial planets in very tenuous gas disks. In slightly more massive disks, we show that massive CO atmospheres can be accreted, forming planets with up to sub-Neptune-like pressures. Our new results demonstrate that new secondary atmospheres with high metallicities and high C/O ratios will be created in these late gas disks, resetting their primordial compositions inherited from the protoplanetary disk phase, and providing a new birth to planets that lost their atmosphere to photoevaporation or giant impacts. We therefore propose a new paradigm for the formation of atmospheres on low-mass planets, which can be tested with future observations (JWST, ELT, ARIEL). We also show that this late accretion would show a very clear signature in Sub-Neptunes or cold exo-Jupiters. Finally, we find that accretion creates cavities in late gas disks, which could be used as a new planet detection method, for low mass planets a few au to a few tens of au from their host stars.
- [46] arXiv:2004.02506 [pdf, other]
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Title: An experimental study of the surface formation of methane in interstellar molecular cloudsSubjects: Solar and Stellar Astrophysics (astro-ph.SR); Earth and Planetary Astrophysics (astro-ph.EP); Astrophysics of Galaxies (astro-ph.GA)
Methane is one of the simplest stable molecules that is both abundant and widely distributed across space. It is thought to have partial origin from interstellar molecular clouds, which are near the beginning of the star formation cycle. Observational surveys of CH$_4$ ice towards low- and high-mass young stellar objects showed that much of the CH$_4$ is expected to be formed by the hydrogenation of C on dust grains, and that CH$_4$ ice is strongly correlated with solid H$_2$O. Yet, this has not been investigated under controlled laboratory conditions, as carbon-atom chemistry of interstellar ice analogues has not been experimentally realized. In this study, we successfully demonstrate with a C-atom beam implemented in an ultrahigh vacuum apparatus the formation of CH$_4$ ice in two separate co-deposition experiments: C + H on a 10 K surface to mimic CH$_4$ formation right before H$_2$O ice is formed on the dust grain, and C + H + H$_2$O on a 10 K surface to mimic CH$_4$ formed simultaneously with H$_2$O ice. We confirm that CH$_4$ can be formed by the reaction of atomic C and H, and that the CH$_4$ formation rate is 2 times greater when CH$_4$ is formed within a H$_2$O-rich ice. This is in agreement with the observational finding that interstellar CH$_4$ and H$_2$O form together in the polar ice phase, i.e., when C- and H-atoms simultaneously accrete with O-atoms on dust grains. For the first time, the conditions that lead to interstellar CH$_4$ (and CD$_4$) ice formation are reported, and can be incorporated into astrochemical models to further constrain CH$_4$ chemistry in the interstellar medium and in other regions where CH$_4$ is inherited.
- [47] arXiv:2004.02508 [pdf, other]
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Title: Multiwavelength study of potential blazar candidates among Fermi-LAT unidentified gamma-ray sourcesComments: 3 pages, IAUS356 Proceedings paperSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
Studying unidentified {\gamma}-ray sources is important as they may hide new discoveries. We conducted a multiwavelength analysis of 13 unidentified Fermi-LAT sources in the 3FGL catalog that have no known counterparts (Unidentified Gamma-ray Sources, UnIDs). The sample was selected for sources that have a single radio and X-ray candidate counterpart in their uncertainty ellipses. The purpose of this study is to find a possible blazar signature and to model the Spectral Energy Distribution (SED) of the selected sources using an empirical log parabolic model. The results show that the synchrotron emission of all sources peaks in the infrared (IR) band and that the high-energy emission peaks in MeV to GeV bands. The SEDs of sources in our sample are all blazar like. In addition, the peak position of the sample reveals that 6 sources (46%) are Low Synchrotron Peaked (LSP) blazars, 4 (31%) of them are High Synchrotron Peaked (HSP) blazars, while 3 of them (23%) are Intermediate Synchrotron Peaked (ISP) blazars.
- [48] arXiv:2004.02512 [pdf, other]
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Title: The origin of Neptune's unusual satellites from a planetary encounterComments: 6 figures; AJ 159 184Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
The Neptunian satellite system is unusual, comprising Triton, a large ($\sim2700$ km) moon on a close-in, circular, yet retrograde orbit, flanked by Nereid, the largest irregular satellite ($\sim$300 km) on a highly eccentric orbit. Capture origins have been previously suggested for both moons. Here we explore an alternative in-situ formation model where the two satellites accreted in the circum-Neptunian disk and are imparted irregular and eccentric orbits by a deep planetary encounter with an ice giant (IG), like that predicted in the Nice scenario of early solar system development. We use $N$-body simulations of an IG approaching Neptune to 20 Neptunian radi ($R_\mathrm{Nep}$), through a belt of circular prograde regular satellites at 10-30 $R_\mathrm{Nep}$. We find that half of these primordial satellites remain bound to Neptune and that 0.4-3\% are scattered directly onto wide and eccentric orbits resembling that of Nereid. With better matches to the observed orbit, our model has a success rate comparable to or higher than capture of large Nereid-sized irregular satellites from heliocentric orbit. At the same time, the IG encounter injects a large primordial moon onto a retrograde orbit with specific angular momentum similar to Triton's in 0.3-3\% of our runs. While less efficient than capture scenarios (Agnor & Hamilton 2006), our model does indicate that an in-situ origin for Triton is dynamically possible. We also simulate the post-encounter collisional and tidal orbital evolution of Triton analogue satellites and find they are decoupled from Nereid on timescales of $\sim$$10^4$ years, in agreement with Cuk & Gladman (2005).
- [49] arXiv:2004.02550 [pdf, other]
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Title: Mode conversion of two-fluid shocks in a partially-ionised, isothermal, stratified atmosphereComments: Accepted for publication in A&ASubjects: Solar and Stellar Astrophysics (astro-ph.SR); Space Physics (physics.space-ph)
The plasma of the lower solar atmosphere consists of mostly neutral particles, whereas the upper solar atmosphere is mostly ionised particles and electrons. A shock that propagates upwards in the solar atmosphere therefore undergoes a transition where the dominant fluid is either neutral or ionised. An upwards propagating shock also passes a point where the sound and Alfv\'en speed are equal. At this point the energy of the acoustic shock can separated into fast and slow components. How the energy is distributed between the two modes depends on the angle of magnetic field. The separation of neutral and ionised species in a gravitationally stratified atmosphere is investigated. The role of two-fluid effects on the structure of the shocks post-mode-conversion and the frictional heating is quantified for different levels of collisional coupling. Two-fluid numerical simulations are performed using the (P\underline{I}P) code of a wave steepening into a shock in an isothermal, partially-ionised atmosphere. The collisional coefficient is varied to investigate the regimes where the plasma and neutral species are weakly, strongly and finitely coupled. The propagation speeds of the compressional waves hosted by neutral and ionised species vary, therefore velocity drift between the two species is produced as the plasma attempts to propagate faster than the neutrals. This is most extreme for a fast-mode shock. We find that the collisional coefficient drastically changes the features present in the system, specifically the mode conversion height, type of shocks present, and the finite shock widths created by the two-fluid effects. In the finitely-coupled regime fast-mode shock widths can exceed the pressure scale height leading to a new potential observable of two-fluid effects in the lower solar atmosphere.
- [50] arXiv:2004.02638 [pdf, ps, other]
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Title: The Effect of Massive Neutrinos on the Galaxy Spin Flip PhenomenonAuthors: Jounghun Lee (1), Noam I Libeskind (2 and 3), Suho Ryu (1) ((1) Seoul National University, (2) Leibniz-Institut für Astrophysik Potsdam, (3) University of Lyon)Comments: 5 pages, 7 figures, comments welcomeSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
The galaxy spin flip refers to the phenomenon that the spin axes of galaxies with masses above a certain threshold tend to be preferentially aligned perpendicular to the hosting large-scale filaments, while low mass or early type galaxies tend to have their spin axes aligned parallel to such structures. Extensive work has so far been conducted to understand this phenomenon under the assumption of cold dark matter and suggested that its origin should be closely related to the nonlinear evolution of the galaxy angular momentum in the anisotropic cosmic web. We present, for the first time, a numerical examination of this phenomenon assuming the presence of massive neutrinos, finding a clear and robust dependence of the threshold mass for the spin flip on the total neutrino mass. Our physical explanation is that the presence of more massive neutrinos retard the nonlinear evolution of the cosmic web, which in turn allows the galaxy spin vectors to better retain their memories of the initial tidal interactions even in the highly nonlinear regime. Our finding in principle implies that the statistical alignment of galaxy spins with the large-scale structures can be used as a probe of the total neutrino mass.
- [51] arXiv:2004.02650 [pdf, other]
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Title: Time-dependent high-energy gamma-ray signal from accelerated particles in core-collapse supernovae: the case of SN 1993JAuthors: Pierre Cristofari, Matthieu Renaud, Alexandre Marcowith, Vikram V. Dwarkadas, Vincent TatischeffComments: Accepted to MNRAS, 7 pages, 7 figuresSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
Some core-collapse supernovae are likely to be efficient cosmic-ray accelerators up to the PeV range, and therefore, to potentially play an important role in the overall Galactic cosmic-ray population. The TeV gamma-ray domain can be used to study particle acceleration in the multi-TeV and PeV range. This motivates the study of the detectability of such supernovae by current and future gamma-ray facilities. The gamma-ray emission of core-collapse supernovae strongly depends on the level of the two-photon annihilation process: high-energy gamma-ray photons emitted at the expanding shock wave following the supernova explosion can interact with soft photons from the supernova photosphere through the pair production channel, thereby strongly suppressing the flux of gamma rays leaving the system. In the case of SN 1993J, whose photospheric and shock-related parameters are well measured, we calculate the temporal evolution of the expected gamma-ray attenuation by accounting for the temporal and geometrical effects. We find the attenuation to be of about $10$ orders of magnitude in the first few days after the SN explosion. The probability of detection of a supernova similar to SN 1993J with the Cherenkov Telescope Array is highest if observations are performed either earlier than 1 day, or later than 10 days after the explosion, when the gamma-ray attenuation decreases to about $2$ orders of magnitude.
- [52] arXiv:2004.02663 [pdf, other]
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Title: Modeling the complete set of Cassini's UVIS occultation observations of Enceladus' plumeSubjects: Earth and Planetary Astrophysics (astro-ph.EP)
The Cassini Ultraviolet Imaging Spectrograph (UVIS) observed a plume of water vapor spewing out from the south polar regions of Enceladus in occultation geometry 7 times during the Cassini mission. Five of them yielded data resolved spatially that allowed fits to a set of individually modeled jets. We created a direct simulation Monte Carlo (DSMC) model to simulate individual water vapor jets with the aim of fitting them to water vapor abundance along the UVIS line of sight during occultation observations. Accurate location and attitude of spacecraft together with positions of Enceladus and Saturn at each observation determine the relationship between the three-dimensional water vapor number density in the plume and the two-dimensional profiles of water vapor abundances along the line of sight recorded by UVIS. By individually fitting observed and modeled jets, every occultation observation of UVIS presented a unique perspective to the physical properties and distribution of the jets. The minimum velocity of water vapor in the jets is determined from the narrowest observed individual jet profile: it ranges from 800 m/s to 1.8 km/s for the UVIS occultation observations. 41 individual jets were required to fit the highest resolution UVIS dataset taken during the Solar occultation however, an alternative larger set of linearly-dependent jets can not be excluded without invoking additional preferably unrelated data from other instruments. A smaller number of jets is required to fit the stellar occultation data because of their spatial resolution and geometry. We identify a set of 37 jets that were repeatedly present in best fits to several UVIS occultation observations. These jets were probably active through the whole Cassini mission.
- [53] arXiv:2004.02698 [pdf, other]
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Title: Mass Functions of Giant Molecular Clouds and Young Star Clusters in Six Nearby GalaxiesComments: 26 pages, 10 figures; accepted for publication in the Astrophysical JournalSubjects: Astrophysics of Galaxies (astro-ph.GA)
We compare the mass functions of young star clusters (ages $\leq 10$ Myr) and giant molecular clouds (GMCs) in six galaxies that cover a large range in mass, metallicity, and star formation rate (LMC, M83, M51, NGC 3627, the Antennae, and NGC 3256). We perform maximum-likelihood fits of the Schechter function, $\psi(M) = dN/dM \propto M^{\beta} \exp(-M/M_*)$, to both populations. We find that most of the GMC and cluster mass functions in our sample are consistent with a pure power-law distribution ($M_* \rightarrow \infty$). M51 is the only galaxy that shows some evidence for an upper cutoff ($M_*$) in both populations. Therefore, physical upper mass cutoffs in populations of both GMCs and clusters may be the exception rather than the rule. When we perform power-law fits, we find a range of indices $\beta_{\rm PL}=-2.3\pm0.3$ for our GMC sample and $\beta_{\rm PL}=-2.0\pm0.3$ for the cluster sample. This result, that $\beta_{\rm Clusters} \approx \beta_{\rm GMC} \approx -2$, is consistent with theoretical predictions for cluster formation and suggests that the star-formation efficiency is largely independent of mass in the GMCs.
- [54] arXiv:2004.02703 [pdf, other]
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Title: TXS 2116$-$077: A Gamma-ray Emitting Relativistic Jet Hosted in a Galaxy MergerAuthors: Vaidehi S. Paliya, Enrique Pérez, Rubén García-Benito, Marco Ajello, Francisco Prada, Antxon Alberdi, Hyewon Suh, C. H. Ishwara Chandra, Alberto Domínguez, Stefano Marchesi, Tiziana Di Matteo, Dieter Hartmann, Marco ChiabergeComments: 13 pages, 7 figures, 1 table, published in the Astrophysical JournalSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics of Galaxies (astro-ph.GA)
What triggers collimated relativistic outflows or jets, from the centers of galaxies remains a fundamental question in astrophysics. The merging of two galaxies has been proposed to realize the conditions to successfully launch and drive such jets into the intergalactic medium. However, evidences for the operation of this mechanism are scarce. Here we report the first unambiguous detection of an ongoing merger of a narrow-line Seyfert 1 galaxy, TXS 2116$-$077, hosting a closely aligned, $\gamma$-ray emitting relativistic jet with a Seyfert 2 galaxy at a separation of $\sim$12 kpc, using the observations taken with 8.2 m Subaru telescope. Our subsequent followup observations with 10.4 m Gran Telescopio Canarias, 4.2 m William Herschel Telescope, and Chandra X-ray observatory have provided what is likely to be the first glimpse of the merging environment hosting a closely aligned relativistic jet. Our finding that the jet is considerably younger than the merger demonstrates that jet activity can be triggered by galaxy mergers and that $\gamma$-ray detected narrow-line Seyfert 1 galaxies represent the beginning phase of that activity. These results also highlight the crucial role of mergers in shaping the fate of galaxies in their cosmological evolution and are consistent with recent studies focused on the host galaxy imaging of this enigmatic class of active galactic nuclei.
- [55] arXiv:2004.02713 [pdf, other]
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Title: Infrared luminosity functions and dust mass functions in the EAGLE simulationAuthors: Maarten Baes, Ana Trčka, Peter Camps, James Trayford, Antonios Katsianis, Lucia Marchetti, Tom Theuns, Mattia Vaccari, Bert VandenbrouckeComments: 13 pages, 6 pages, accepted for publication in MNRASSubjects: Astrophysics of Galaxies (astro-ph.GA)
We present infrared luminosity functions and dust mass functions for the EAGLE cosmological simulation, based on synthetic multi-wavelength observations generated with the SKIRT radiative transfer code. In the local Universe, we reproduce the observed infrared luminosity and dust mass functions very well. Some minor discrepancies are encountered, mainly in the high luminosity regime, where the EAGLE-SKIRT luminosity functions mildly but systematically underestimate the observed ones. The agreement between the EAGLE-SKIRT infrared luminosity functions and the observed ones gradually worsens with increasing lookback time. Fitting modified Schechter functions to the EAGLE-SKIRT luminosity and dust mass functions at different redshifts up to $z=1$, we find that the evolution is compatible with pure luminosity/mass evolution. The evolution is relatively mild: within this redshift range, we find an evolution of $L_{\star,250}\propto(1+z)^{1.68}$, $L_{\star,\text{TIR}}\propto(1+z)^{2.51}$ and $M_{\star,\text{dust}}\propto(1+z)^{0.83}$ for the characteristic luminosity/mass. For the luminosity/mass density we find $\varepsilon_{250}\propto(1+z)^{1.62}$, $\varepsilon_{\text{TIR}}\propto(1+z)^{2.35}$ and $\rho_{\text{dust}}\propto(1+z)^{0.80}$, respectively. The mild evolution of the dust mass density is in relatively good agreement with observations, but the slow evolution of the infrared luminosity underestimates the observed luminosity evolution significantly. We argue that these differences can be attributed to increasing limitations in the radiative transfer treatment due to increasingly poorer resolution, combined with a slower than observed evolution of the SFR density in the EAGLE simulation and the lack of AGN emission in our EAGLE-SKIRT post-processing recipe.
- [56] arXiv:2004.02715 [pdf, other]
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Title: New high-quality strong lens candidates with deep learning in the Kilo Degree SurveyAuthors: R. Li, N. R. Napolitano, C. Tortora, C. Spiniello, L. V. E. Koopmans, Z. Huang, G. Vernardos, S. Chatterjee, B. Giblin, F. Getman, G. CovoneComments: Submitted to APJSubjects: Astrophysics of Galaxies (astro-ph.GA)
We report new high-quality galaxy scale strong lens candidates found in the Kilo Degree Survey data release 4 using Machine Learning. We have developed a new Convolutional Neural Network (CNN) classifier to search for gravitational arcs, following the prescription by Petrillo et al. 2019 and using only $r-$band images. We have applied the CNN to two "predictive samples": a Luminous red galaxy (LRG) and a "bright galaxy" (BG) sample ($r<21$). We have found 286 new high probability candidates, 133 from the LRG sample and 153 from the BG sample. We have then ranked these candidates based on a value that combines the CNN likelihood to be a lens and the human score resulting from visual inspection (P-value) and we present here the highest 82 ranked candidates with P-values $\ge 0.5$. All these high-quality candidates have obvious arc or point-like features around the central red defector. Moreover, we define the best 26 objects, all with scores P-values $\ge 0.7$ as a "golden sample" of candidates. This sample is expected to contain very few false positives and thus it is suitable for follow-up observations. The new lens candidates come partially from the the more extended footprint adopted here with respect to the previous analyses, partially from a larger predictive sample (also including the BG sample). These results show that machine learning tools are very promising to find strong lenses in large surveys and more candidates that can be found by enlarging the predictive samples beyond the standard assumption of LRGs. In the future, we plan to apply our CNN to the data from next-generation surveys such as the Large Synoptic Survey Telescope, Euclid, and the Chinese Space Station Optical Survey.
- [57] arXiv:2004.02728 [pdf]
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Title: Sulfur-driven Haze Formation in Warm CO2-rich Exoplanet AtmospheresAuthors: Chao He, Sarah M. Horst, Nikole K. Lewis, Xinting Yu, Julianne I. Moses, Patricia McGuiggan, Mark S. Marley, Eliza M.-R. Kempton, Sarah E. Moran, Caroline V. Morley, Veronique VuittonJournal-ref: Nature Astronomy 2020Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Sulfur gases significantly affect the photochemistry of planetary atmospheres in our Solar System, and are expected to be important components in exoplanet atmospheres. However, sulfur photochemistry in the context of exoplanets is poorly understood due to a lack of chemical-kinetics information for sulfur species under relevant conditions. Here, we study the photochemical role of hydrogen sulfide (H2S) in warm CO2-rich exoplanet atmospheres (800 K) by carrying out laboratory simulations. We find that H2S plays a significant role in photochemistry, even when present in the atmosphere at relatively low concentrations (1.6%). It participates in both gas and solid phase chemistry, leading to the formation of other sulfur gas products (CH3SH/SO, C2H4S/OCS, SO2/S2, and CS2) and to an increase in solid haze particle production and compositional complexity. Our study shows that we may expect thicker haze with small particle sizes (20 to 140 nm) for warm CO2-rich exoplanet atmospheres that possess H2S.
- [58] arXiv:2004.02761 [pdf, other]
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Title: Bayesian methods for fitting Baryon Acoustic Oscillations in the Lyman-$α$ forestComments: 18 pages, 4 figuresSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
We study and compare fitting methods for the Lyman-$\alpha$ (Ly$\alpha$) forest 3D correlation function. We use the nested sampler PolyChord and the community code picca to perform a Bayesian analysis which we compare with previous frequentist analyses. By studying synthetic correlation functions, we find that the frequentist profile likelihood produces results in good agreement with a full Bayesian analysis. On the other hand, Maximum Likelihood Estimation with the Gaussian approximation for the uncertainties is inadequate for current data sets. We compute for the first time the full posterior distribution from the Ly$\alpha$ forest correlation functions measured by the extended Baryon Oscillation Spectroscopic Survey (eBOSS). We highlight the benefits of sampling the full posterior distribution by expanding the baseline analysis to better understand the contamination by Damped Ly$\alpha$ systems (DLAs). We make our improvements and results publicly available as part of the picca package.
- [59] arXiv:2004.02765 [pdf, other]
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Title: Blazar variability power spectra from radio up to TeV photon energies: Mrk 421 and PKS 2155-304Authors: Arti GoyalComments: MNRAS acceptedSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
We present the results of the power spectral density (PSD) analysis for the blazars Mrk\,421 and PKS\,2155$-$304, using good-quality, densely sampled light curves at multiple frequencies, covering 17 decades of the electromagnetic spectrum, and variability timescales from weeks up to a decade. The data were collected from publicly available archives of observatories at radio from OVRO, optical and infrared (B, V, R, I, J, H, and K-bands), X-rays from the {\it Swift} and the {\it Rossi} X-ray Timing Explorer, high and very high energy $\gamma-$rays from the {\it Fermi} and Very Energetic Radiation Imaging Telescope Array System as well as the High Energy Stereoscopic System. Our results are: (1) the power-law form of the variability power spectra at radio, infra-red and optical frequencies have slopes $\sim$1.8, indicative of random-walk type noise processes; (2) the power-law form of the variability power spectra at higher frequencies, from X-rays to very high energy \,$\gamma$-rays, however, have slopes $\sim$1.2, suggesting a flicker noise type process; (3) there is significantly more variability power at X-rays, high and very high energy $\gamma$-rays on timescales $\lesssim$ 100 days, as compared to lower energies. Our results do not easily fit into a simple model, in which a single compact emission zone is dominating the radiative output of the blazars across all the timescales probed in our analysis. Instead, we argue that the frequency-dependent shape of the variability power spectra points out a more complex picture, with highly inhomogeneous outflow producing non-thermal emission over an extended, stratified volume.
- [60] arXiv:2004.02775 [pdf, ps, other]
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Title: Velocity Response of the Observed Explosive Events in the Lower Solar Atmosphere: I. Formation of the Flowing Cool Loop SystemAuthors: A.K. Srivastava, Yamini K. Rao, P. Konkol, K. Murawski, M. Mathioudakis, Sanjiv K. Tiwari, E. Scullion, J.G. Doyle, B.N. DwivediComments: In Press; The Astrophysical Journal; 14 Pages; 9 FiguresSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
We observe plasma flows in cool loops using the Slit-Jaw Imager (SJI) onboard the Interface Region Imaging Spectrometer (IRIS). Huang et al. (2015) observed unusually broadened Si IV 1403 angstrom line profiles at the footpoints of such loops that were attributed to signatures of explosive events (EEs). We have chosen one such uni-directional flowing cool loop system observed by IRIS where one of the footpoints is associated with significantly broadened Si IV line profiles. The line profile broadening indirectly indicates the occurrence of numerous EEs below the transition region (TR), while it directly infers a large velocity enhancement /perturbation further causing the plasma flows in the observed loop system. The observed features are implemented in a model atmosphere in which a low-lying bi-polar magnetic field system is perturbed in the chromosphere by a velocity pulse with a maximum amplitude of 200 km/s. The data-driven 2-D numerical simulation shows that the plasma motions evolve in a similar manner as observed by IRIS in the form of flowing plasma filling the skeleton of a cool loop system. We compare the spatio-temporal evolution of the cool loop system in the framework of our model with the observations, and conclude that their formation is mostly associated with the velocity response of the transient energy release above their footpoints in the chromosphere/TR. Our observations and modeling results suggest that the velocity responses most likely associated to the EEs could be one of the main candidates for the dynamics and energetics of the flowing cool loop systems in the lower solar atmosphere.
- [61] arXiv:2004.02815 [pdf]
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Title: The turbulent dynamics of Jupiter's and Saturn's weather layers: order out of chaos?Comments: 27 pages, including 7 figures. Submitted to Geoscience Letters as invited review from 2019 assembly of the Asia-Oceania Geosciences SocietySubjects: Earth and Planetary Astrophysics (astro-ph.EP)
The weather layers of the gas giant planets, Jupiter and Saturn, comprise the shallow atmospheric layers that are influenced energetically by a combination of incoming solar radiation and localised latent heating of condensates, as well as by upwelling heat from their planetary interiors. They are also the most accessible regions of those planets to direct observations. Recent analyses in Oxford of cloud-tracked winds on Jupiter have demonstrated that kinetic energy is injected into the weather layer at scales comparable to the Rossby radius of deformation and cascades both upscale, mostly into the extra-tropical zonal jets, and downscale to the smallest resolvable scales in Cassini images. The large-scale flow on both Jupiter and Saturn appears to equilibrate towards a state which is close to marginal instability according to Arnol'd's 2nd stability theorem. This scenario is largely reproduced in a hierarchy of numerical models of giant planet weather layers, including relatively realistic models which seek to predict thermal and dynamical structures using a full set of parameterisations of radiative transfer, interior heat sources and even moist convection. Such models include the Jason GCM, developed in Oxford, which also represents the formation of (energetically passive) clouds of NH3, NH4SH and H2O condensates and the transport of condensable tracers. Recent results show some promise in comparison with observations from the Cassini and Juno missions, but some observed features (such as Jupiter's Great Red Spot and other compact ovals) are not yet captured spontaneously by any weather layer model. We review recent work in this vein and discuss a number of open questions for future study.
- [62] arXiv:2004.02862 [pdf, other]
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Title: Detection of Repeating FRB 180916.J0158+65 Down to Frequencies of 300 MHzAuthors: P. Chawla, B. C. Andersen, M. Bhardwaj, E. Fonseca, A. Josephy, V. M. Kaspi, D. Michilli, Z. Pleunis, K. M. Bandura, C. G. Bassa, P. J. Boyle, T. Cassanelli, D. Cubranic, M. Dobbs, F. Q. Dong, B. M. Gaensler, D. C. Good, J. W. T. Hessels, T. L. Landecker, C. Leung, D. Z. Li, H. -. H. Lin, K. Masui, R. Mckinven, J. Mena-Parra, M. Merryfield, B. W. Meyers, A. Naidu, C. Patel, M. Rafiei-Ravandi, M. Rahman, P. Sanghavi, P. Scholz, K. Shin, K. M. Smith, I. H. Stairs, S. P. Tendulkar, K. VanderlindeComments: Submitted to ApJ LettersSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
We report on the detection of seven bursts from the periodically active, repeating fast radio burst (FRB) source FRB 180916.J0158+65 in the 300-400-MHz frequency range with the Green Bank Telescope (GBT). Emission in multiple bursts is visible down to the bottom of the GBT band, suggesting that the cutoff frequency (if it exists) for FRB emission is lower than 300 MHz. Observations were conducted during predicted periods of activity of the source, and had simultaneous coverage with the Low Frequency Array (LOFAR) and the FRB backend on the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope. We find that one of the GBT-detected bursts has potentially associated emission in the CHIME band (400-800 MHz) but we detect no bursts in the LOFAR band (110-190 MHz), placing a limit of $\alpha > -1.0$ on the spectral index of broadband emission from the source. We also find that emission from the source is severely band-limited with burst bandwidths as low as $\sim$40 MHz. In addition, we place the strictest constraint on observable scattering of the source, $<$ 1.7 ms, at 350 MHz, suggesting that the circumburst environment does not have strong scattering properties. Additionally, knowing that the circumburst environment is optically thin to free-free absorption at 300 MHz, we find evidence against the association of a hyper-compact HII region or a young supernova remnant (age $<$ 50 yr) with the source.
Cross-lists for Tue, 7 Apr 20
- [63] arXiv:1810.03722 (cross-list from hep-ph) [pdf, other]
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Title: Photon enhancement in a homogeneous axion dark matter backgroundAuthors: Ariel ArzaComments: 4 pages, 3 figuresSubjects: High Energy Physics - Phenomenology (hep-ph); Astrophysics of Galaxies (astro-ph.GA)
We study the propagation of photons in a homogeneous axion dark matter background. When the axion decay into two photons is stimulated, the photon field exhibits a parametric instability in a small bandwidth centered on one half of the axion mass. We estimate analytically the enhancement for both coherent and non-coherent axion fields and we find that this effect could be relevant in the context of miniclusters and galactic halos.
- [64] arXiv:2004.02024 (cross-list from physics.ins-det) [pdf, other]
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Title: SiPM-matrix readout of two-phase argon detectors using electroluminescence in the visible and near infrared rangeAuthors: The DarkSide collaboration: C. E. Aalseth, S. Abdelhakim, P. Agnes, R. Ajaj, I. F. M. Albuquerque, T. Alexander, A. Alici, A. K. Alton, P. Amaudruz, F. Ameli, J. Anstey, P. Antonioli, M. Arba, S. Arcelli, R. Ardito, I. J. Arnquist, P. Arpaia, D. M. Asner, A. Asunskis, M. Ave, H. O. Back, V. Barbaryan, A. Barrado Olmedo, G. Batignani, M. G. Bisogni, V. Bocci, A. Bondar, G. Bonfini, W. Bonivento, E. Borisova, B. Bottino, M. G. Boulay, R. Bunker, S. Bussino, A. Buzulutskov, M. Cadeddu, M. Cadoni, A. Caminata, N. Canci, A. Candela, C. Cantini, M. Caravati, M. Cariello, F. Carnesecchi, A. Castellani, P. Castello, P. Cavalcante, D. Cavazza, S. Cavuoti, S. Cebrian, J. M. Cela Ruiz, B. Celano, R. Cereseto, S. Chashin, W. Cheng, A. Chepurnov, C. Cicalò, L. Cifarelli, M. Citterio, F. Coccetti, et al. (254 additional authors not shown)Comments: 25 pages, 22 figures, 3 tablesSubjects: Instrumentation and Detectors (physics.ins-det); Instrumentation and Methods for Astrophysics (astro-ph.IM); High Energy Physics - Experiment (hep-ex)
Proportional electroluminescence (EL) in noble gases is used in two-phase detectors for dark matter search to record (in the gas phase) the ionization signal induced by particle scattering in the liquid phase. The "standard" EL mechanism is considered to be due to noble gas excimer emission in the vacuum ultraviolet (VUV). In addition to it, there are two alternative mechanisms, producing light in the visible and near infrared (NIR) range. The first is due to bremsstrahlung of electrons scattered on neutral atoms (so-called neutral bremsstrahlung, NBrS). The second, responsible for electron avalanche scintillations in the NIR at higher electric fields, is due to transitions between excited atomic states. In this work, we have for the first time demonstrated two alternative techniques of the optical readout of two-phase argon detectors, in the visible and NIR range, using a SiPM matrix and electroluminescence due to either neutral bremsstrahlung or avalanche scintillations effects. The amplitude yield and position resolution were measured for these readout techniques, which allowed to assess the detection threshold for electron and nuclear recoils in two-phase argon detectors for dark matter search. It should be emphasized that this is the first practical application of the NBrS effect in detection science.
- [65] arXiv:2004.02058 (cross-list from physics.ins-det) [pdf, other]
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Title: Position reconstruction using photon timing for the DEAP-3600 dark matter experimentAuthors: Yu ChenComments: 7 pages, 4 figures, contribution to the Proceedings of "LIDINE 2019: LIght Detection In Noble Elements", University of Manchester, 28-30 August 2019Subjects: Instrumentation and Detectors (physics.ins-det); Instrumentation and Methods for Astrophysics (astro-ph.IM); High Energy Physics - Experiment (hep-ex)
DEAP-3600 is a single-phase liquid argon dark matter detector being operated 2 km underground at SNOLAB, Sudbury, Canada. The detector consists of 3.3 tonnes of ultra-pure liquid argon in a spherical acrylic cryostat instrumented with 255 photomultiplier tubes. Natural radioactive contamination in the acrylic vessel or TPB wavelength shifter can alpha-decay. Reconstruction of the position of the interactions taking place in the detector uses information about the number of photoelectrons detected in each PMT and when they were detected. Including this information in our suite of cuts allows us to identify and remove almost all surface background events. A method of event position reconstruction emphasizing photon timing is presented here.
- [66] arXiv:2004.02332 (cross-list from hep-ph) [pdf, other]
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Title: Gravitational Waves from Pati-Salam DynamicsComments: 12 pages, 6 figuresSubjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Theory (hep-th)
We show that it is possible to use gravitational wave detectors to observe the occurrence of a first order phase transition in Pati-Salam extensions of the Standard Model. We show that the peak frequency of the expected gravitational wave signals ranges within $0.1-10$ Hz. We find amusing that the next generation of gravity waves detectors are able to explore time honoured extensions of the Standard Model occurring at energy scales inaccessible by present and future particle physics accelerators.
- [67] arXiv:2004.02527 (cross-list from gr-qc) [pdf, other]
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Title: Interpreting Binary Neutron Star Mergers: Describing the Binary Neutron Star Dynamics, Modelling Gravitational Waveforms, and Analyzing DetectionsComments: invited review for General Relativity and Gravitation; any comment or suggestion is welcomeSubjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Astrophysical Phenomena (astro-ph.HE)
Gravitational waves emitted from the coalescence of neutron star binaries open a new window to probe matter and fundamental physics in unexplored, extreme regimes. To extract information about the supranuclear matter inside neutron stars and the properties of the compact binary systems, robust theoretical prescriptions are required. We give an overview about general features of the dynamics and the gravitational wave signal during the binary neutron star coalescence. We briefly describe existing analytical and numerical approaches to investigate the highly dynamical, strong-field region during the merger. We review existing waveform approximants and discuss properties and possible advantages and shortcomings of individual waveform models, and their application for real gravitational-wave data analysis.
- [68] arXiv:2004.02602 (cross-list from gr-qc) [pdf, other]
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Title: Orbital mechanics for, and QPOs' resonances in, black holes of Einstein-Æther theoryAuthors: Mustapha Azreg-Aïnou, Zihang Chen, Bojun Deng, Mubasher Jamil, Tao Zhu, Qiang Wu, Yen-Kheng LimComments: 21 pages, 15 captioned figuresSubjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Theory (hep-th)
In this paper, we study the motion of test particles around two exact charged black-hole solutions in Einstein-{\AE}ther theory. Specifically, we first consider the quasi-periodic oscillations (QPOs) and their resonances generated by the particle moving in the Einstein-{\AE}ther black hole and then turn to study the periodic orbits of the massive particles. For QPOs, we drop the usually adopted assumptions $\nu_U=\nu_\theta$, $\nu_L=\nu_r$, and $\nu_U/\nu_L=3/2$ with $\nu_U$ ($\nu_L$) and $\nu_r$ ($\nu_\theta$) being the upper (lower) frequency of QPOs and radial (vertical) epicyclic frequency of the orbiting particles, respectively. Instead, we put-forward a new working ansatz for which the Keplerian radius is much closer to that of the innermost stable circular orbit and explore in details the effects of the {\ae}ther field on the frequencies of QPOs. We then realize good curves for the frequencies of QPOs, which fit to data of three microquasars very well by ignoring any effects of rotation and magnetic fields. For the study of the periodic orbits of massive particle moving in the two Einstein-{\AE}ther black hole solutions, we first consider the geodesic equations in the two black holes and solve the geodesic equation for one of black hole (the black hole with \ae{}ther parameter $c_{14}=0$ but $c_{123}\neq 0$) analytically. The innermost stable circular orbits are also analyzed and we find the isco radius increases with increasing $c_{13}$ for the first type black hole while decreases with increasing $c_{14}$ for the second one. We also obtain several periodic orbits and find that they share similar taxonomy schemes as the periodic equatorial orbits in the Schwarzschild/Kerr metrics. The equations for null geodesics are also briefly considered, where we study circular photon orbits and bending angles for gravitational lensing.
- [69] arXiv:2004.02654 (cross-list from gr-qc) [pdf, other]
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Title: Extreme mass ratio inspirals with spinning secondary: a detailed study of equatorial circular motionComments: 14+12 pages, 6 figures. Longer companion paper of arXiv:2003.08448. Data available at this https URLSubjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph)
Extreme mass-ratio inspirals detectable by the future Laser Interferometer Space Antenna provide a unique way to test general relativity and fundamental physics. Motivated by this possibility, here we study in detail the EMRI dynamics in the presence of a spinning secondary, collecting and extending various results that appeared in previous work and also providing useful intermediate steps and new relations for the first time. We present the results of a frequency-domain code that computes gravitational-wave fluxes and the adiabatic orbital evolution for the case of circular, equatorial orbits with (anti)aligned spins. The spin of the secondary starts affecting the gravitational-wave phase to next-to-leading order in the mass ratio (being thus comparable to the leading-order conservative part and to the second-order dissipative part of the self-force) and introduces a detectable dephasing, which can be used to measure it at $5-25\%$ level, depending on individual spins. In a companion paper we discuss the implication of this effect for tests of the Kerr bound.
- [70] arXiv:2004.02675 (cross-list from physics.ins-det) [pdf]
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Title: Simulations and Design of a Single-Photon CMOS Imaging Pixel Using Multiple Non-Destructive Signal SamplingAuthors: Konstantin D. Stefanov, Martin Prest, Mark Downing, Elizabeth George, Naidu Bezawada, Andrew D. HollandComments: 12 page, 8 figures. Published in Sensors Special Issue: Multipixels Single Photon Detectors for Quantum ApplicationsJournal-ref: Sensors 2020, 20(7), 2031Subjects: Instrumentation and Detectors (physics.ins-det); Instrumentation and Methods for Astrophysics (astro-ph.IM)
A single-photon CMOS image sensor design based on pinned photodiode (PPD) with multiple charge transfers and sampling is described. In the proposed pixel architecture, the photogenerated signal is sampled non-destructively multiple times and the results are averaged. Each signal measurement is statistically independent and by averaging the electronic readout noise is reduced to a level where single photons can be distinguished reliably. A pixel design using this method has been simulated in TCAD and several layouts have been generated for a 180 nm CMOS image sensor process. Using simulations, the noise performance of the pixel has been determined as a function of the number of samples, sense node capacitance, sampling rate, and transistor characteristics. The strengths and the limitations of the proposed design are discussed in detail, including the trade-off between noise performance and readout rate and the impact of charge transfer inefficiency. The projected performance of our first prototype device indicates that single-photon imaging is within reach and could enable ground-breaking performance in many scientific and industrial imaging applications.
- [71] arXiv:2004.02733 (cross-list from hep-ph) [pdf, other]
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Title: Searching for solar axions at the Sudbury Neutrino ObservatoryComments: 5 pages, 1 figureSubjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO)
We explore a novel detection possibility for solar axions, which relies only on their couplings to nucleons, via the axion-induced dissociation of deuterons into their constituent neutrons and protons. An opportune target for this process is the now-concluded Sudbury Neutrino Observatory (SNO) experiment, which relied upon large quantities of heavy water to resolve the solar neutrino problem. From the full SNO dataset we exclude in a model-independent fashion isovector axion-nucleon couplings $|g^3_{aN}|\equiv\frac{1}{2}|g_{an}-g_{ap}|>2\times10^{-5}$GeV${}^{-1}$ at 95 % C.L. for sub-MeV axion masses, covering previously unexplored regions of the axion parameter space. In the absence of a precise cancellation between $g_{an}$ and $g_{ap}$ this result also exceeds comparable constraints from other laboratory experiments, and excludes regions of the parameter space for which astrophysical constraints from SN1987A and neutron star cooling are inapplicable due to axion trapping.
- [72] arXiv:2004.02840 (cross-list from gr-qc) [pdf, other]
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Title: Imprints of the Janis-Newman-Winicour spacetime on observations related to shadow and accretionComments: 21 pages, 8 figuresSubjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics of Galaxies (astro-ph.GA); High Energy Astrophysical Phenomena (astro-ph.HE)
The final fate of gravitational collapse of massive stars has been a subject of interest for a long time since such a collapse may lead to black holes and naked singularities alike. Since, the formation of naked singularities is forbidden by the cosmic censorship conjecture, exploring their observational differences from black holes may be a possible avenue to search for these exotic objects. The simplest possible naked singularity spacetime emerges from the Einstein massless scalar field theory with the advantage that it smoothly translates to the Schwarzschild solution by the variation of the scalar charge. This background, known as the Janis-Newman-Winicour spacetime is the subject of interest in this work. We explore electromagnetic observations around this metric which involves investigating the characteristics of black hole accretion and shadow. We compute the shadow radius in this spacetime and compare it with the image of M87*, recently released by the Event Horizon Telescope Collaboration. Similarly, we derive the expression for the luminosity from the accretion disk and compare it with the observed optical luminosity of eighty Palomar Green quasars. Our analysis indicates that the shadow of M87* favors the Schwarzschild background while the quasars on the other hand exhibit the existence of a non-trivial scalar charge from the accretion data thereby supporting the Janis-Newman-Winicour spacetime. The implications of this result are discussed.
Replacements for Tue, 7 Apr 20
- [73] arXiv:1509.08457 (replaced) [pdf, other]
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Title: The External Field Dominated Solution In QUMOND & AQUAL: Application To Tidal StreamsComments: 5 pages, 2 figures, 1 table. References updated, typos fixedJournal-ref: ScieFed Journal of Astrophysics, 1, 1000008 (2018)Subjects: Astrophysics of Galaxies (astro-ph.GA)
- [74] arXiv:1806.02505 (replaced) [pdf, ps, other]
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Title: Torsion driven Inflationary MagnetogenesisComments: 18 pages no figures, minor changesSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)
- [75] arXiv:1809.04854 (replaced) [pdf, other]
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Title: Multi-feature universe: large parameter space cosmology and the swamplandAuthors: Deng WangComments: 7 pages, 5 figures, 2 figs added, accepted version in Physics of the Dark UniverseSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph)
- [76] arXiv:1901.09210 (replaced) [pdf, ps, other]
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Title: Refinement of initial conditions for cosmological $N$-body simulationsAuthors: Takayuki TatekawaComments: 18 pages, 13 figures; ver.3. Major revisionSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [77] arXiv:1904.07872 (replaced) [pdf, other]
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Title: Self-Interacting Dark Matter Subhalos in the Milky Way's TidesComments: 6 pages, 3 figures. Updated figures and text. Accepted for publication in PRLSubjects: Astrophysics of Galaxies (astro-ph.GA); High Energy Physics - Phenomenology (hep-ph)
- [78] arXiv:1905.02278 (replaced) [pdf, other]
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Title: Super-CMB fluctuations and the Hubble tensionComments: 7 pages, 3 figures; v3: title changed, discussion of SDDR added, and other minor changes made to match published versionSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Theory (hep-th)
- [79] arXiv:1905.03450 (replaced) [pdf, other]
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Title: Axion core - halo mass and the black hole - halo mass relation: constraints on a few parsec scalesComments: (v1): 7 pages, 1 figure. To be submitted to MNRAS (v2): matches published versionSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Phenomenology (hep-ph)
- [80] arXiv:1905.04896 (replaced) [pdf, other]
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Title: Turbulent pressure support and hydrostatic mass-bias in the intracluster mediumAuthors: M. Angelinelli, F. Vazza, C. Giocoli, S. Ettori, T.W. Jones, G. Brunetti, M. Brüggen, D. EckertComments: 20 pages; 21 figures; Substantial Revision; MNRAS in pressSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [81] arXiv:1905.07335 (replaced) [pdf, other]
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Title: Description of CRESST-III DataAuthors: CRESST Collaboration: A. H. Abdelhameed, G. Angloher, P. Bauer, A. Bento, E. Bertoldo, C. Bucci, L. Canonica, A. D'Addabbo, X. Defay, S. Di Lorenzo, A. Erb, F. v. Feilitzsch, S. Fichtinger, N. Ferreiro Iachellini, A. Fuss, P. Gorla, D. Hauff, J. Jochum, A. Kinast, H. Kluck, H. Kraus, A. Langenkämper, M. Mancuso, V. Mokina, E. Mondragon, A. Münster, M. Olmi, T. Ortmann, C. Pagliarone, L. Pattavina, F. Petricca, W. Potzel, F. Pröbst, F. Reindl, J. Rothe, K. Schäffner, J. Schieck, V. Schipperges, D. Schmiedmayer, S. Schönert, C. Schwertner, M. Stahlberg, L. Stodolsky, C. Strandhagen, R. Strauss, C. Türkoglu, I. Usherov, M. Willers, V. ZemaComments: Added appendix with information for better reproducibilitySubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Instrumentation and Methods for Astrophysics (astro-ph.IM)
- [82] arXiv:1907.03775 (replaced) [pdf, other]
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Title: Screened Fifth Forces Mediated by Dark Matter-Baryon Interactions: Theory and Astrophysical ProbesComments: Eqn. 40 corrected and Fig. 7 (right) updated. Conclusions unchangedJournal-ref: Phys. Rev. D 100, 104035 (2019)Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)
- [83] arXiv:1907.12418 (replaced) [pdf, ps, other]
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Title: Void-dominated Cosmic Fluid: A Possible Estimation of the Cosmological ConstantComments: 6 pages, 3 figures, 1 table, Some sentences have been corrected in the abstract, text and resultsSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [84] arXiv:1907.13130 (replaced) [pdf, other]
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Title: Rapid Reionization by the Oligarchs: The Case for Massive, UV-Bright, Star-Forming Galaxies with High Escape FractionsAuthors: Rohan P. Naidu, Sandro Tacchella, Charlotte A. Mason, Sownak Bose, Pascal A. Oesch, Charlie ConroyComments: Accepted for publication in ApJSubjects: Astrophysics of Galaxies (astro-ph.GA); Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [85] arXiv:1908.05038 (replaced) [pdf, other]
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Title: Asymmetric accretion and thermal `mountains' in magnetized neutron star crustsComments: 13 pages, 6 figures, accepted by MNRASSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [86] arXiv:1908.08543 (replaced) [pdf, other]
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Title: A Real-Time Search for Interstellar Impacts on the MoonComments: 4 pages, 3 figures; accepted for publication in Acta AstronauticaSubjects: Earth and Planetary Astrophysics (astro-ph.EP)
- [87] arXiv:1909.04641 (replaced) [pdf, other]
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Title: Constraining structure formation using EDGESComments: 20 pages, 3 figures. Minor changes to text and figures, some references added. Published in JCAPJournal-ref: JCAP04(2020)004Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [88] arXiv:1910.00429 (replaced) [pdf, ps, other]
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Title: Observing a wormholeComments: 5 figures, accepted by PRDSubjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Theory (hep-th)
- [89] arXiv:1910.02361 (replaced) [pdf, ps, other]
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Title: Detectability of 21cm signal during the Epoch of Reionization with 21cm-Lyman-$α$ emitter cross-correlation. III. Model dependenceComments: 11 pages, 10 figures, accepted to Monthly Notices of the Royal Astronomical SocietySubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [90] arXiv:1910.03797 (replaced) [pdf, other]
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Title: Predicting the next local supernovaAuthors: John Middleditch (University of California, retired)Comments: 10 pages, 1 figure, v7 "(even in \textit{un}-red/blueshifted H-alpha" in abstractSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [91] arXiv:1910.06305 (replaced) [pdf, other]
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Title: The impact of relativistic effects on the 3D Quasar-Lyman-$α$ cross-correlationComments: 22 pages, 10 figures; added appendix on lensing; version matches one published in JCAPJournal-ref: JCAP04(2020)006Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [92] arXiv:1910.12917 (replaced) [pdf, other]
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Title: Probing dark matter signals in neutrino telescopes through angular power spectrumComments: 13 pages, 9 figures. v2: KM3NeT results updated after correcting the effective area normalizationSubjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Astrophysical Phenomena (astro-ph.HE)
- [93] arXiv:1910.14336 (replaced) [pdf, ps, other]
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Title: Magnetar birth: rotation rates and gravitational-wave emissionComments: 10 pages, 7 figures. Version accepted for publication in MNRAS; includes short discussion on FRBs and additional figure not in v1Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc)
- [94] arXiv:1911.01426 (replaced) [pdf, other]
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Title: Mass Segregation in Eccentric Nuclear Disks: Enhanced Tidal Disruption Event Rates for High Mass StarsComments: 14 pages, 13 figures, Accepted to ApJJournal-ref: ApJ, 890, 175 (2020)Subjects: Astrophysics of Galaxies (astro-ph.GA); High Energy Astrophysical Phenomena (astro-ph.HE)
- [95] arXiv:1911.01660 (replaced) [pdf, other]
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Title: The thermal-radiative wind in low mass X-ray binary H 1743-322: II. iron line predictions from Monte Carlo radiation transferComments: 8 gages, 12 figures, accepted by MNRASSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [96] arXiv:1911.04499 (replaced) [pdf, other]
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Title: Two-year Cosmology Large Angular Scale Surveyor (CLASS) Observations: 40 GHz Telescope Pointing, Beam Profile, Window Function, and Polarization PerformanceAuthors: Zhilei Xu, Michael K. Brewer, Pedro Fluxá Rojas, Yunyang Li, Keisuke Osumi, Bastián Pradenas, Aamir Ali, John W. Appel, Charles L. Bennett, Ricardo Bustos, Manwei Chan, David T. Chuss, Joseph Cleary, Jullianna Denes Couto, Sumit Dahal, Rahul Datta, Kevin L. Denis, Rolando Dünner, Joseph R. Eimer, Thomas Essinger-Hileman, Dominik Gothe, Kathleen Harrington, Jeffrey Iuliano, John Karakla, Tobias A. Marriage, Nathan J. Miller, Carolina Núñez, Ivan L. Padilla, Lucas Parker, Matthew A. Petroff, Rodrigo Reeves, Karwan Rostem, Deniz Augusto Nunes Valle, Duncan J. Watts, Janet Weiland, Edward J. WollackComments: 32 pages, 24 figures, published in ApJJournal-ref: The Astrophysical Journal, 891:134 (25pp), 2020 March 10Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)
- [97] arXiv:1911.09073 (replaced) [pdf, other]
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Title: Hints, neutrino bounds and WDM constraints from SDSS DR14 Lyman-$α$ and Planck full-survey dataAuthors: Nathalie Palanque-Delabrouille, Christophe Yèche, Nils Schöneberg, Julien Lesgourgues, Michael Walther, Solène Chabanier, Eric ArmengaudComments: accepted for publication in JCAPSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [98] arXiv:1911.09674 (replaced) [pdf, other]
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Title: The dynamics of stratified horizontal shear flows at low Péclet numberComments: 36 pages, 9 figuresSubjects: Fluid Dynamics (physics.flu-dyn); Solar and Stellar Astrophysics (astro-ph.SR)
- [99] arXiv:1912.10354 (replaced) [pdf, other]
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Title: The Broad-lined Ic Supernova ZTF18aaqjovh (SN 2018bvw): An Optically-discovered Engine-driven Supernova Candidate with Luminous Radio EmissionAuthors: Anna Y. Q. Ho (1), Alessandra Corsi (2), S. Bradley Cenko (3 and 4), Francesco Taddia (5), S. R. Kulkarni (1), Scott Adams (1), Kishalay De (1), Richard Dekany (6), Dmitry D. Frederiks (7), Christoffer Fremling (1), V. Zach Golkhou (8 and 9), Thomas Kupfer (10), Russ R. Laher (11), Ashish Mahabal (1 and 12), Frank J. Masci (11), Adam A. Miller (13 and 14), James D. Neill (6), Daniel Reiley (6), Reed Riddle (6), Anna Ridnaia (7), Ben Rusholme (11), Yashvi Sharma (1), Jesper Sollerman (5), Maayane T. Soumagnac (15 and 16), Dmitry S. Svinkin (7), David L. Shupe (11) ((1) Cahill Center for Astrophysics, Caltech, (2) Texas Tech University, (3) NASA Goddard, (4) University of Maryland, (5) Stockholm University, (6) Caltech Optical Observatories, (7) Ioffe Institute, (8) DIRAC Institute, University of Washington, (9) The eScience Institute, University of Washington, (10) Kavli Institute for Theoretical Physics, UCSB, (11) IPAC, Caltech, (12) Center for Data Driven Discovery, Caltech, (13) CIERA, Northwestern, (14) Adler Planetarium, (15) LBNL, (16) Weizmann Institute of Science)Comments: 18 pages, 8 figures. Accepted to the Astrophysical Journal on 2 March 2020. Revised from proofs on 4 Apr 2020Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [100] arXiv:1912.12538 (replaced) [pdf, other]
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Title: Full of Orions: a 200-pc mapping of the interstellar medium in the redshift-3 lensed dusty star-forming galaxy SDP.81Comments: 27 pages, 22 figures. 24 MB in total. MNRAS accepted 2020 March 17. Data available on requestSubjects: Astrophysics of Galaxies (astro-ph.GA)
- [101] arXiv:2001.00588 (replaced) [pdf, other]
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Title: The Gravitational Wave Treasure Map: A Tool to Coordinate, Visualize, and Assess the Electromagnetic Follow-Up of Gravitational Wave EventsAuthors: Samuel D. Wyatt, Aaron Tohuvavohu, Iair Arcavi, Michael J. Lundquist, D. Andrew Howell, David J. SandComments: 14 pages, 8 figures, Accepted to ApJSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); Instrumentation and Methods for Astrophysics (astro-ph.IM)
- [102] arXiv:2001.00838 (replaced) [pdf, other]
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Title: Dynamical Simulations of the First Globular ClustersAuthors: Raymond G. CarlbergComments: ApJ accepted, editedSubjects: Astrophysics of Galaxies (astro-ph.GA); Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [103] arXiv:2001.00930 (replaced) [pdf, other]
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Title: Observational evidence for the origin of high-energy neutrinos in parsec-scale nuclei of radio-bright active galaxiesAuthors: A.V. Plavin (ASC Lebedev, MIPT), Y.Y. Kovalev (ASC Lebedev, MIPT, MPIfR), Y.A. Kovalev (ASC Lebedev), S.V. Troitsky (INR)Comments: 19 pages, 5 figures, 3 tables; accepted to ApJ; v2: extended discussion, added a figure and electronic tableSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics of Galaxies (astro-ph.GA)
- [104] arXiv:2001.02451 (replaced) [pdf, other]
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Title: Is the Hubble tension a hint of AdS phase around recombination?Comments: 7 pages, 5 figures, matched published version in PRDSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)
- [105] arXiv:2001.10492 (replaced) [pdf, other]
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Title: The Birth Function for Black Holes and Neutron Stars in Close BinariesComments: submitted to ApJSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); Solar and Stellar Astrophysics (astro-ph.SR)
- [106] arXiv:2002.01367 (replaced) [pdf, other]
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Title: The observed velocity distribution of young pulsars II: analysis of complete PSR$π$Authors: Andrei P. IgoshevComments: 13 pages, 14 figures. Accepted to the MNRAS 2020 April 2Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [107] arXiv:2002.01920 (replaced) [pdf, other]
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Title: FRB-periodicity: mild pulsars in tight O/B-star binariesComments: 13 pages, 4 figuresSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [108] arXiv:2002.01972 (replaced) [pdf, ps, other]
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Title: Consistent Blandford-Znajek ExpansionComments: corrected few typosJournal-ref: JCAP 04 (2020) 009Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)
- [109] arXiv:2002.04621 (replaced) [pdf, other]
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Title: Dynamical friction-driven orbital circularisation in rotating discs: a semi-analytical descriptionComments: 7 pages, 3 figures, accepted for publication in MNRASSubjects: Astrophysics of Galaxies (astro-ph.GA); High Energy Astrophysical Phenomena (astro-ph.HE)
- [110] arXiv:2002.06918 (replaced) [pdf, ps, other]
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Title: Can we constrain the extragalactic magnetic field from very high energy observations of GRB 190114C?Comments: 6 pages, 3 figuresSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [111] arXiv:2002.09257 (replaced) [pdf, other]
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Title: Gas fractions and depletion times in galaxies with different degrees of interactionComments: Accepted for publication in A&A (February 21, 2020). 6 pages, 5 figuresSubjects: Astrophysics of Galaxies (astro-ph.GA)
- [112] arXiv:2002.11496 (replaced) [pdf, other]
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Title: On three-body decay ratesAuthors: Barak KolComments: 8 pagesSubjects: General Relativity and Quantum Cosmology (gr-qc); Earth and Planetary Astrophysics (astro-ph.EP); High Energy Physics - Theory (hep-th)
- [113] arXiv:2003.00285 (replaced) [pdf, other]
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Title: Linearized model for satellite station-keeping and tandem formations under the effects of atmospheric dragAuthors: David ArnasComments: 30 pages, 7 figuresSubjects: Earth and Planetary Astrophysics (astro-ph.EP); Space Physics (physics.space-ph)
- [114] arXiv:2003.02360 (replaced) [pdf, other]
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Title: The binary mass ratio in the black hole transient MAXI J1820+070Authors: M. A. P. Torres, J. Casares, F. Jiménez-Ibarra, A. Álvarez-Hernández, T. Muñoz-Darias, M. Armas Padilla, P. G. Jonker, M. HeidaComments: 8 pages, 2 figures. Accepted for publication in ApJLSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [115] arXiv:2003.02776 (replaced) [pdf, other]
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Title: Mean-Field Alpha Effect impacts Memory of the Solar CycleComments: 12 pages, 5 figures, Draft Version, Under Revision, Subject to ChangeSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
- [116] arXiv:2003.06874 (replaced) [pdf, other]
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Title: A dark matter telescope probing the 6 to 60 GHz bandAuthors: Javier De Miguel-HernándezComments: 26 pages, 8 figuresSubjects: Instrumentation and Detectors (physics.ins-det); High Energy Astrophysical Phenomena (astro-ph.HE); Instrumentation and Methods for Astrophysics (astro-ph.IM); High Energy Physics - Experiment (hep-ex); High Energy Physics - Phenomenology (hep-ph)
- [117] arXiv:2003.07446 (replaced) [pdf, other]
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Title: The Low Earth Orbit Satellite Population and Impacts of the SpaceX Starlink ConstellationAuthors: Jonathan C. McDowellComments: 20 pages, 14 figures. Published in Ap J LettersJournal-ref: ApJ 892 (2020), L36Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)
- [118] arXiv:2003.08516 (replaced) [pdf, ps, other]
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Title: Palatini quadratic gravity: spontaneous breaking of gauged scale symmetry and inflationAuthors: D. M. GhilenceaComments: 18 pages, 2 figures, LaTeXSubjects: High Energy Physics - Theory (hep-th); Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph)
- [119] arXiv:2003.08832 (replaced) [pdf, other]
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Title: Galaxy rotation curves from external influence on Schwarzschild geometryAuthors: A. BhattacharyayComments: 5 pages and one figure. This version adds the Einstein tensor for the system and its explanation and also provides other detailed explanation of the results which were not given in the previous versionSubjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics of Galaxies (astro-ph.GA)
- [120] arXiv:2003.09437 (replaced) [pdf, other]
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Title: A Deep CFHT Optical Search for a Counterpart to the Possible Neutron Star -- Black Hole Merger GW190814Authors: Nicholas Vieira, John J. Ruan, Daryl Haggard, Maria R. Drout, Melania C. Nynka, Hope Boyce, Kristine Spekkens, Samar Safi-Harb, Raymond G. Carlberg, Rodrigo Fernández, Anthony L. Piro, Niloufar Afsariardchi, Dae-Sik MoonComments: 20 pages, 14 figures including appendices; submitted to ApJ; updated legend of figure 5Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [121] arXiv:2003.09613 (replaced) [pdf, ps, other]
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Title: Suspended and restored activities of A Nearby Super Massive Black HoleComments: 8 pages, 4 figures and 1 table, accepted for publication in AJ (matches accepted version). arXiv admin note: text overlap with arXiv:1910.02392Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Astrophysics of Galaxies (astro-ph.GA)
- [122] arXiv:2003.10154 (replaced) [pdf, ps, other]
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Title: Boltzmann's $H$-theorem, entropy and the strength of gravity in theories with a nonminimal coupling between matter and geometryComments: 6 pages, no figures. Minor typos corrected, missing term in Boltzmann's equation inserted and accounted for. Main results unchangedSubjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Theory (hep-th)
- [123] arXiv:2003.12722 (replaced) [pdf, other]
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Title: Power and spatial complexity in stochastic reconnectionSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); Plasma Physics (physics.plasm-ph)
- [124] arXiv:2003.12876 (replaced) [pdf, other]
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Title: Screened fifth forces lower the TRGB-calibrated Hubble constant tooComments: 10 pages, 3 figures; correction to Eq 1, results changed slightly, conclusions unaffectedSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Solar and Stellar Astrophysics (astro-ph.SR); General Relativity and Quantum Cosmology (gr-qc)
- [125] arXiv:2003.14336 (replaced) [pdf, other]
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Title: HD 196390: A tight correlation of differential abundances with condensation temperatureComments: An updated and expanded version of a paper accepted by Research Notes of the AAS. Minor typos fixedSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
- [126] arXiv:2004.01196 (replaced) [pdf, other]
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Title: Fundamental differences in the radio properties of red and blue quasars: Insight from the LOFAR Two-metre Sky Survey (LoTSS)Authors: D. J. Rosario, V. A. Fawcett, L. Klindt, D. M. Alexander, L. K. Morabito (CEA, Durham University), S. Fotopoulou (University of Bristol), E. Lusso (University of Florence, INAF-Arcetri), G. Calistro Rivera (ESO)Comments: 20 pages, 16 Figures. Accepted for publication in MNRASSubjects: Astrophysics of Galaxies (astro-ph.GA)
- [127] arXiv:2004.01197 (replaced) [pdf, other]
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Title: Fundamental differences in the radio properties of red and blue quasars: enhanced compact AGN emission in red quasarsAuthors: V. A. Fawcett, D. J. Rosario, D. M. Alexander, L. Klindt (CEA, Durham University), S. Fotopoulou (University of Bristol), E. Lusso (University of Florence, INAF-Arcetri), L. K. Morabito (CEA, Durham University), G. Calistro Rivera (ESO)Comments: 17 pages, 17 Figures. Accepted for publication in MNRASSubjects: Astrophysics of Galaxies (astro-ph.GA)
- [128] arXiv:2004.01633 (replaced) [pdf, ps, other]
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Title: Stellar laboratories. X. New Cu IV - VII oscillator strengths and the first detection of copper and indium in hot white dwarfsAuthors: T. Rauch (1), S. Gamrath (2), P. Quinet (2,3), M. Demleitner (4), M. Knoerzer (1), K. Werner (1), J. W. Kruk (5) ((1) Institute for Astronomy and Astrophysics, Eberhard Karls University, Tuebingen, Germany, (2) Physique Atomique et Astrophysique, Universite de Mons - UMONS, Belgium, (3) IPNAS, Universite de Liege, Liege, Belgium, (4) Astronomisches Rechen-Institut, Zentrum fuer Astronomie, Ruprecht Karls University, Heidelberg, Germany, (5) NASA Goddard Space Flight Center, Greenbelt, USA)Comments: 32 pages, 7 figuresSubjects: Solar and Stellar Astrophysics (astro-ph.SR); Atomic Physics (physics.atom-ph)
- [129] arXiv:2004.01645 (replaced) [pdf, other]
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Title: Modeling the formation of the $^{13}$C neutron source in AGB starsComments: 4 pages, 2 figures, NPA IX proceedings. Accepted in JPCSSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
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