arXiv:0904.1003 [ps, pdf, other] Title: Halo streams in the 7th SDSS data release Authors: R. Klement (MPIA), H.-W. Rix (MPIA), C. Flynn (Tuorla), B. Fuchs (ARI), T. C. Beers (MSU), C. Allende Prieto (UT), D. Bizyaev (APO), H. Brewington (APO), Y. S. Lee (MSU), E. Malanushenko (APO), V. Malanushenko (APO), D. Oravetz (APO), K. Pan (APO), P. Re Fiorentin (MPIA), A. Simmons (APO), S. Snedden (APO) Comments: 57 pages, 22 figures, accepted for publication in ApJ Subjects: Galaxy Astrophysics (astro-ph.GA) We have detected stellar halo streams in the solar neighborhood using data from the 7th public data release of the Sloan Digital Sky Survey (SDSS), which includes the directed stellar program SEGUE: Sloan Extension For Galactic Understanding and Exploration. In order to derive distances to each star, we used the metallicity-dependent photometric parallax relation from Ivezic et al. (2008) for which we examine and quantify the accuracy. Our final sample consists of 22,321 nearby (d < 2 kpc), metal-poor ([Fe/H] < -0.5) main-sequence stars with 6D estimates of position and space velocity. We characterize the orbits of these stars through suitable kinematic proxies for their "effective" integrals of motion, angular momentum, eccentricity, and orbital polar angle and compare the observed distribution to expectations from a smooth distribution in four [Fe/H] bins. On this basis we identify at least five significant "phase-space overdensities" of stars on very similar orbits in the solar neighborhood to which we can assign unambiguously peaked [Fe/H] distributions. Three of them have been identified previously, including the halo stream discovered by Helmi et al. (1999) at a significance level of 12.0. In addition, we find at least two new genuine halo streams, judged by their kinematics and [Fe/H], at significance levels of 2.9 and 4.8, respectively. For one stream the stars even show coherence in configuration space, matching a spatial overdensity of stars found by Juric et al. (2008) at (R,z) \approx (9.5,0.8) kpc. Our results demonstrate the practical power of our search method to detect substructure in the phase-space distribution of nearby stars without making a-priori assumptions about the detailed form of the gravitational potential. date for proposal to council: dec 2010 arXiv:0904.1012 [pdf, other] Title: Kinematics of SDSS subdwarfs: Structure and substructure of the Milky Way halo Authors: M.C. Smith (1), N.W. Evans (1), V. Belokurov (1), P.C. Hewett (1), D.M. Bramich (2), G. Gilmore (1), M.J. Irwin (1), S. Vidrih (3), D.B. Zucker (4) ((1) Cambridge, (2) ING, (3) Heidelberg, (4) Macquarie) Comments: 14 pages, 11 figures, submitted to MNRAS Subjects: Galaxy Astrophysics (astro-ph.GA); Cosmology and Extragalactic Astrophysics (astro-ph.CO) We construct a new sample of ~1800 solar neighbourhood halo subdwarfs from the Sloan Digital Sky Survey, selected using a reduced proper motion diagram. Radial velocities come from the SDSS spectra and proper motions from the light-motion curve catalogue of Bramich et al. (2008). Using a photometric parallax relation to estimate distances gives us the full phase-space coordinates. Typical velocity errors are in the range 30-50 km/s. This halo sample is one of the largest constructed to-date and the disc contamination is at a level of < 0.1 per cent. This enables us to calculate the halo velocity dispersion to excellent accuracy. We find that the velocity dispersion tensor is aligned in spherical polar coordinates and that (sigma_r, sigma_phi, sigma_theta) = (142 \pm 2, 81 \pm 2, 77 \pm 2) km/s. The stellar halo exhibits no net rotation, although the distribution of v_phi shows tentative evidence for asymmetry. The kinematics are consistent with a mildly flattened stellar density falling with distance like r^{-3.8}. Using the full phase-space coordinates, we look for signs of kinematic substructure in the stellar halo. We find evidence for four discrete overdensities localised in angular momentum and suggest that they may be possible accretion remnants. The most prominent is the solar neighbourhood stream previously identified by Helmi et al. (1999), but the remaining three are new. One of these overdensities is potentially associated with a group of four globular clusters (NGC5466, NGC6934, M2 and M13) and raises the possibility that these could have been accreted as part of a much larger progenitor. arXiv:0904.1126 [ps, pdf, other] Title: Cosmologists in the dark Authors: Vicent J. Martinez, Virginia Trimble Comments: 10 pages, ASP style (asp2006.sty), invited talk, to be published in the proceedings of the conference "Cosmology across Cultures" (held at Granada, Spain, on 2008, September 8th to 12th), J. A. Belmonte, F. Prada, J. A. Rubino Martin, & A. Alberdi, Eds., ASP, S. Francisco. Comments are welcome Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO) We review the present status of cosmological discoveries and how these confirm our modern cosmological model, but at the same time we try to focus on its weaknesses and inconsistencies with an historical perspective, and foresee how the on-going big cosmological projects may change in the future our view of the universe. arXiv:0904.1126 [ps, pdf, other] Title: Cosmologists in the dark Authors: Vicent J. Martinez, Virginia Trimble Comments: 10 pages, ASP style (asp2006.sty), invited talk, to be published in the proceedings of the conference "Cosmology across Cultures" (held at Granada, Spain, on 2008, September 8th to 12th), J. A. Belmonte, F. Prada, J. A. Rubino Martin, & A. Alberdi, Eds., ASP, S. Francisco. Comments are welcome Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO) We review the present status of cosmological discoveries and how these confirm our modern cosmological model, but at the same time we try to focus on its weaknesses and inconsistencies with an historical perspective, and foresee how the on-going big cosmological projects may change in the future our view of the universe. [1] arXiv:0904.1200 [ps, pdf, other] Title: BLAST: Correlations in the Cosmic Far-Infrared Background at 250, 350, and 500 microns Reveal Clustering of Star-Forming Galaxies Authors: Marco P. Viero, Peter A. R. Ade, James J. Bock, Edward L. Chapin, Mark J. Devlin, Matthew Griffin, Joshua O. Gundersen, Mark Halpern, Peter C. Hargrave, David H. Hughes, Jeff Klein, Carrie J. MacTavish, Gaelen Marsden, Peter G. Martin, Philip Mauskopf, Lorenzo Moncelsi, Mattia Negrello, Calvin B. Netterfield, Luca Olmi, Enzo Pascale, Guillaume Patanchon, Marie Rex, Douglas Scott, Christopher Semisch, Nicholas Thomas, Matthew D. P. Truch, Carole Tucker, Gregory S. Tucker, Donald V. Wiebe Comments: Submitted to ApJ. Maps and other results available at this http URL Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO) We detect correlations in the cosmic far-infrared background due to the clustering of star-forming galaxies, in observations made with the Balloon-borne Large Aperture Submillimeter Telescope (BLAST), at 250, 350, and 500 microns. Since the star-forming galaxies which make up the far-infrared background are expected to trace the underlying dark matter in a biased way, measuring clustering in the far-infrared background provides a way to relate star formation directly to structure formation. We test the plausibility of the result by fitting a simple halo model to the data. We derive an effective bias b_eff = 2.2 +/- 0.2, effective mass log(M_eff/M_sun) = 13.2 (+0.3/-0.8), and minimum mass log(M_min/M_sun) = 9.9 (+1.5/-1.7). This is the first robust clustering measurement at submillimeter wavelengths. arXiv:0904.1201 [pdf] Title: Over half of the far-infrared background light comes from galaxies at z >= 1.2 Authors: Mark J. Devlin, Peter A. R. Ade, Itziar Aretxaga, James J. Bock, Edward L. Chapin, Matthew Griffin, Joshua O. Gundersen, Mark Halpern, Peter C. Hargrave, David H. Hughes, Jeff Klein, Gaelen Marsden, Peter G. Martin, Philip Mauskopf, Lorenzo Moncelsi, Calvin B. Netterfield, Henry Ngo, Luca Olmi, Enzo Pascale, Guillaume Patanchon, Marie Rex, Douglas Scott, Christopher Semisch, Nicholas Thomas, Matthew D. P. Truch, Carole Tucker, Gregory S. Tucker, Marco P. Viero, Donald V. Wiebe Comments: Accepted to Nature. Maps available at this http URL Journal-ref: Nature, vol. 458, 737-739 (2009) Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO) Submillimetre surveys during the past decade have discovered a population of luminous, high-redshift, dusty starburst galaxies. In the redshift range 1 <= z <= 4, these massive submillimetre galaxies go through a phase characterized by optically obscured star formation at rates several hundred times that in the local Universe. Half of the starlight from this highly energetic process is absorbed and thermally re-radiated by clouds of dust at temperatures near 30 K with spectral energy distributions peaking at 100 microns in the rest frame. At 1 <= z <= 4, the peak is redshifted to wavelengths between 200 and 500 microns. The cumulative effect of these galaxies is to yield extragalactic optical and far-infrared backgrounds with approximately equal energy densities. Since the initial detection of the far-infrared background (FIRB), higher-resolution experiments have sought to decompose this integrated radiation into the contributions from individual galaxies. Here we report the results of an extragalactic survey at 250, 350 and 500 microns. Combining our results at 500 microns with those at 24 microns, we determine that all of the FIRB comes from individual galaxies, with galaxies at z >= 1.2 accounting for 70 per cent of it. As expected, at the longest wavelengths the signal is dominated by ultraluminous galaxies at z > 1. arXiv:0904.1204 [ps, pdf, other] Title: Radio and mid-infrared identification of BLAST source counterparts in the Chandra Deep Field South Authors: Simon Dye, Peter A. R. Ade, James J. Bock, Edward L. Chapin, Mark J. Devlin, James S. Dunlop, Stephen A. Eales, Matthew Griffin, Joshua O. Gundersen, Mark Halpern, Peter C. Hargrave, David H. Hughes, Jeff Klein, Gaelen Marsden, Philip Mauskopf, Lorenzo Moncelsi, Calvin B. Netterfield, Luca Olmi, Enzo Pascale, Guillaume Patanchon, Marie Rex, Douglas Scott, Christopher Semisch, Nicholas Thomas, Matthew D. P. Truch, Carole Tucker, Gregory S. Tucker, Marco P. Viero, Donald V. Wiebe Comments: Submitted to ApJ. Maps available at this http URL Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO) We have identified radio and/or mid-infrared counterparts to 198 out of 351 sources detected at >= 5 sigma over ~ 9 sq. degrees centered on the Chandra Deep Field South (CDFS) by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) at 250, 350, and 500 microns. We have matched 92 of these counterparts to optical sources with previously derived photometric redshifts and fitted SEDs to the BLAST fluxes and fluxes at 70 and 160 microns acquired with the Spitzer Space Telescope. In this way, we have constrained dust temperatures, total far-infrared/submillimeter luminosities and star formation rates for each source. Our findings show that the BLAST sources lie at significantly lower redshifts and have significantly lower rest-frame dust temperatures compared to submm sources detected in surveys conducted at 850 microns. We demonstrate that an apparent increase in dust temperature with redshift in our sample arises as a result of selection effects. This paper constitutes the public release of the multi-wavelength catalog of >= 5 sigma BLAST sources contained within the full ~ 9 sq. degree survey area. arXiv:0904.1205 [ps, pdf, other] Title: BLAST: Resolving the Cosmic Submillimeter Background Authors: Gaelen Marsden, Peter A. R. Ade, James J. Bock, Edward L. Chapin, Mark J. Devlin, Simon R. Dicker, Matthew Griffin, Joshua O. Gundersen, Mark Halpern, Peter C. Hargrave, David H. Hughes, Jeff Klein, Philip Mauskopf, Benjamin Magnelli, Lorenzo Moncelsi, Calvin B. Netterfield, Henry Ngo, Luca Olmi, Enzo Pascale, Guillaume Patanchon, Marie Rex, Douglas Scott, Christopher Semisch, Nicholas Thomas, Matthew D. P. Truch, Carole Tucker, Gregory S. Tucker, Marco P. Viero, Donald V. Wiebe Comments: Submitted to ApJ. Maps are available at this http URL Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO) The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) has made one square-degree, deep, confusion-limited maps at three different bands, centered on the Great Observatories Origins Deep Survey South field. By calculating the covariance of these maps with catalogs of 24 micron sources from the Far-Infrared Deep Extragalactic Legacy Survey (FIDEL), we have determined that the total submillimeter intensities are 8.60 +/- 0.59, 4.93 +/- 0.34, and 2.27 +/- 0.20 nW m^-2 sr^-1 at 250, 350, and 500 microns, respectively. These numbers are more precise than previous estimates of the cosmic infrared background (CIB) and are consistent with 24 micron-selected galaxies generating the full intensity of the CIB. We find that more than half of the CIB originates from sources at z >= 1.2. At all BLAST wavelengths, the relative intensity of high-z sources is higher for 24 micron-faint sources than it is for 24 micron-bright sources. Galaxies identified very broadly as AGN by their Spitzer Infrared Array Camera (IRAC) colors contribute 32-48% of the CIB, although X-ray-selected AGN contribute only 7%. BzK-selected galaxies are found to be brighter than typical 24 micron-selected galaxies in the BLAST bands, and contribute 32-42% of the CIB. These data provide high-precision constraints for models of the evolution of the number density and intensity of star-forming galaxies at high redshift. arXiv:0904.1206 [ps, pdf, other] Title: BLAST: A Far-Infrared Measurement of the History of Star Formation Authors: Enzo Pascale, Peter A. R. Ade, James J. Bock, Edward L. Chapin, Mark J. Devlin, Simon Dye, Steve A. Eales, Matthew Griffin, Joshua O. Gundersen, Mark Halpern, Peter C. Hargrave, David H. Hughes, Jeff Klein, Gaelen Marsden, Philip Mauskopf, Lorenzo Moncelsi, Calvin B. Netterfield, Luca Olmi, Guillaume Patanchon, Marie Rex, Douglas Scott, Christopher Semisch, Nicholas Thomas, Matthew D. P. Truch, Carole Tucker, Gregory S. Tucker, Marco P. Viero, Donald V. Wiebe Comments: Submitted to ApJ. Maps available at this http URL Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO) We use measurements from the Balloon-borne Large Aperture Sub-millimeter Telescope (BLAST) at wavelengths spanning 250 to 500 microns, combined with data from the Spitzer Infrared telescope and ground-based optical surveys in GOODS-S, to determine the average star formation rate of the galaxies that comprise the cosmic infrared background (CIB) radiation from 70 to 500 microns, at redshifts 0 < z < 3. We find that different redshifts are preferentially probed at different wavelengths within this range, with most of the 70 micron background generated at z < ~1 and the 500 micron background generated at z > ~1. The spectral coverage of BLAST and Spitzer in the region of the peak of the background at ~200 microns allows us to directly estimate the mean physical properties (temperature, bolometric luminosity and mass) of the dust in the galaxies responsible for contributing more than 80% of the CIB. By utilizing available redshift information we directly measure the evolution of the far infrared luminosity density and therefore the optically obscured star formation history up to redshift z ~3. arXiv:0904.1209 [ps, pdf, other] Title: The Fundamental Planes of E+A galaxies and GALEX UV-excess early-type galaxies: Revealing their intimate connection Authors: Yumi Choi (1), Tomotsugu Goto (2,3), Suk-Jin Yoon (1) ((1) Yonsei University, (2) ISAS/JAXA, (3) University of Hawaii) Comments: 15 pages, 15 figures, Accepted for publication in MNRAS Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO) Strong Balmer absorption lines and the lack of Ha and [OII] emission lines signify that E+As are post-starburst systems. Recent studies suggest that E+As may undergo the transition from the `blue cloud' to the `red sequence' and eventually migrate to red sequence ETGs. An observational validation of this scenario is to identify the intervening galaxy population between E+As and the red-sequence. Motivated by recent findings with GALEX that a large fraction of ETGs exhibit UV-excess as a sign of RSF, we investigate the possible connection of the UV-excess galaxies to E+As. In particular, we examine the FP scaling relations of the largest sample of ~1,000 E+As selected from the SDSS and ~20,000 morphologically-selected SDSS ETGs with GALEX UV data. The FP parameters, combined with stellar population indicators, reveal a certain group of UV-excess ETGs that bridges between E+As and quiescent red galaxies. The newly identified galaxies are the post-starburst systems characterized by UV-excess but no Ha emission. This is a conceptual generalisation of "E+A", in that the Balmer absorption line in the "E+A" definition is replaced with UV-optical colours that are far more sensitive to RSF than the Balmer lines. We refer to these UV-excess galaxies as "E+a" galaxies, which stands for elliptical ("E") galaxies with a minority of A-type ("a") young stars. The species are either (1) galaxies that experienced starbursts weaker than those observed in E+As (1~10% of E+As, "mild E+As") or (2) the products of passively evolved E+As after quenching star formation quite a while ago (~1 Gyr, "old E+As"). We suggest that the latter type of E+a galaxies represents the most recent arrival to the red sequence in the final phase of the "E+A" to "red early-type" transition. (Abridged) arXiv:0904.1574 [ps, pdf, other] Title: A HR-like diagram for galaxies: the M_BH versus M_G sigma^2 relation Authors: Antonio Feoli (University of Sannio), Luigi Mancini (University of Salerno) Comments: 18 pages, 2 figures Subjects: Galaxy Astrophysics (astro-ph.GA) We show that the relation between the mass of supermassive black holes located in the center of the host galaxies and the kinetic energy of random motions of the corresponding bulges is a useful tool to study the evolution of galaxies. In the form log[M_BH] = b + m log[M_G sigma^2/c^2], the best--fitting results for a sample of 64 galaxies of various morphological types are the slope m=0.82 and the normalization b=4.46. We notice that, in analogy with the HR diagram for stars, each morphological type of galaxy generally occupies a different area in the M_BH - (M_G sigma^2)/c^2 plane. In particular, we find elliptical galaxies in the upper part of the line of best fit, the lenticular galaxies in the middle part, and the late-type galaxies in the lower part, the mass of the central black hole giving an estimate of the age, whereas the kinetic energy of the stellar bulges is directly connected with the temperature of each galactic system. Finally, the values of the linear correlation coefficient and the chi^2 obtained by using the M_BH - M_G sigma^2 relation are better than the corresponding ones obtained from the M_BH - sigma relation. arXiv:0904.2006 [ps, pdf, other] Title: Every BCG with a strong radio AGN has an X-ray cool core Authors: Ming Sun Comments: Submitted to ApJ, emulateapj5.sty, 22 pages, 11 figures and 4 tables,a high-resolution PDF is available at this http URL Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO); High Energy Astrophysical Phenomena (astro-ph.HE) Radio AGN feedback in cool cores has been proposed as a crucial ingredient in the evolution of baryonic structures. However, it has long been known that strong radio AGN also exist in noncool core clusters, which brings up the question whether a cool core is always required for radio feedback. In this work, we present a systematic analysis of BCGs and strong radio AGN in 145 groups and clusters from the Chandra archive. All 65 BCGs with radio AGN more luminous than 2x10^23 W Hz^-1 at 1.4 GHz are found to have X-ray cool cores. The BCG cool cores can be divided into two classes, the large-cool-core (LCC) class and the corona class. Small coronae, easily overlooked at z>0.1, can trigger strong heating episodes in groups and clusters, long before large cool cores are formed. Strong radio outbursts triggered by coronae may destroy embryonic large cool cores and thus provide another mechanism to prevent formation of large cool cores. However, it is unclear whether coronae are decoupled from the radio feedback cycles as they have to be largely immune to strong radio outbursts. Our sample study also shows no groups with luminous cool cores (L_0.5-2 keV > 10^41.8 ergs s^-1) hosting strong radio AGN with L_1.4GHz > 10^24 W Hz^-1, which is not observed in clusters. This may point to a greater impact of radio heating on low-mass systems than clusters. Few L_1.4GHz > 10^24 W Hz^-1 radio AGN (~ 16%) host a L_0.5 - 10 keV > 10^42 ergs s^-1 X-ray AGN, while above these thresholds, all X-ray AGN in BCGs are also radio AGN. As examples of the corona class, we also present detailed analyses of a BCG corona associated with a strong radio AGN (\ga in A3627) and one of the faintest coronae known (NGC 4709 in the Centaurus cluster). arXiv:0904.2032 [ps, pdf, other] Title: Galaxy Assembly and SMBH/AGN-growth from Cosmic Dawn to the End of Reionization Authors: Rolf A. Jansen (1), Rogier Windhorst (1), James Rhoads (1), Sangeeta Malhotra (1), Daniel Stern (2), Robert O'Connell (3), Paul Scowen (1), Matthew Beasley (4) ((1) Arizona State University, (2) NASA/Jet Propulsion Laboratory, (3) University of Virginia, (4) University of Colorado - Boulder) Comments: 8 pages, LaTeX2e requires 'fancyheadings_b.sty' (included), 4 postscript figures. Science White Paper submitted to the Astro2010 Decadal Survey. Compiled high-resolution PDF versions are available from either: this http URL or: this http URL Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO) [abridged] We propose a tiered, UV--near-IR, cosmological broad- and medium-band imaging and grism survey that covers ~10 deg^2 in two epochs to m_AB=28, ~3 deg^2 in seven epochs to m_AB=28, and ~1 deg^2 in 20 epochs to m_AB=30 mag. Such a survey is an essential complement to JWST surveys (<~0.1 deg^2 to m_AB<~31 mag at lambda>1100nm and z>~8). We aim to: (1) understand in how galaxies formed from perturbations in the primordial density field by studying faint Ly\alpha-emitting and Lyman-break galaxies at 5.5<~z<~8 and trace the metal-enrichment of the IGM; (2) measure the evolution of the faint end of the galaxy luminosity function (LF) from z~8 to z~0 by mapping the ramp-up of PopII star formation, (dwarf) galaxy formation and assembly, and hence, the objects that likely completed the H-reionization at z~6; (3) directly study the lambda<91.2nm escape fractions of galaxies and weak AGN from z~4.0--2.5, when the He reionization finished; (4) measure the mass- and environment-dependent galaxy assembly process from z~5 to z~0, combining accurate (sigma_z/(1+z) <~ 0.02) photo-z's with spatially resolved stellar populations and kpc-scale structure for >~5x10^6 galaxies; (5) trace the strongly epoch-dependent galaxy merger rate and constrain how Dark Energy affected galaxy assembly and the growth of SMBHs; (6) study >~10^5 weak AGN/feeding SMBHs in the faint-end of the QSO LF, over 10 deg^2 and measure how the growth of SMBHs kept pace with galaxy assembly and spheroid growth, and how this process was shaped by various feedback processes over cosmic times since z~8. The proposed study is not feasible with current instrumentation but argues for a wide-field (>~250 arcmin^2), high-resolution (<~0.02--0.11 [300--1700 nm]), UV--near-IR imaging facility on a 4m-class space observatory. [1