CHAMP+ is a dual-frequency heterodyne submillimeter array receiver built jointly by MPIfR and NOVA/SRON/DIMES for APEX. The mixer elements are developed and built at SRON and will ship to Bonn in the first half of 2004 for integration into the array. CHAMP+ will ship to Chajnantor in the second half of 2004 and be commissioned in 2005. The Netherlands astronomical community will have access to 42 24-hour observing days in the period of 2005-2010. CHAMP+ will be essential for the spectroscopic exploration of the 'warm' molecular Universe.
| Telescope | APEX |
|---|---|
| Location | Llano de Chajnantor |
| Elevation | 5000 m |
| Telescope Diameter | 12 m |
| Low-frequency band | |
| Number of pixels | 7 beams + 1 spare |
| Array configuration | 2:3:2 |
| RF range | 602-720 GHz (ALMA band 9) |
| Beam size | 9-7 arcsec |
| Mixer DSB noise temperature | <150-200 K |
| Expected Tsys | 1000-1500 K |
| IF | 2 GHz in the 4-8 GHz band |
| IF pass-band ripple | <3dB / 2 GHz |
| Polarization purity | >95% |
| Beam efficiency | >90% (Gaussian beam efficiency) |
| High-frequency band | |
| Number of pixels | 7 beams + 1 spare |
| Array configuration | 2:3:2 |
| RF range | 790-950 GHz (ALMA band 10; large overlap HIFI band 3) |
| Beam size | 7-6 arcsec |
| Mixer DSB noise temperature | <350-400 K |
| Expected Tsys | 1800-2500 K |
| IF | 2 GHz in the 4-8 GHz band |
| IF pass-band ripple | <3dB / 2 GHz |
| Polarization purity | >95% |
| Beam efficiency | >90% (Gaussian beam efficiency) |
Estimated sensitivity of a single pixel in a 2 MHz channel (1 km s-1: appropriate for galactic astronomy) after 20 min of integration: 40-60 mK at 602-720 GHz and 75-105 mK at 790-950 GHz. In a 40 MHz channel (20 km s-1: for extra-galactic astronomy) after 1 hour of integration: 5-8 mK at 602-720 GHz and 9-13 mK at 790-950 GHz.