Multiwavelength Followup of Chandra Fields
Abstract
NASA's Chandra X-ray Observatory (CXO, formerly AXAF), will be launched in 1999. The Chandra Multiwavelength Project (ChaMP) will bring together radio to X-ray observations of Chandra serendipitous X-ray sources, with an optical survey as its backbone. Optical identification of serendipitous X-ray sources has spawned important scientific advances, many unanticipated. However, great challenges have faced such campaigns because of the large ( ~ 1') X-ray positional uncertainties. Chandra's small half-power diameter (<3'') and good positional accuracy ( ~ 1'') enable unambiguous identification of optical counterparts. Even though ChaMP optical followup will exclude targeted deep fields, thanks to Chandra's PSF and its extremely low background, we will include sources as faint as f(0.2-8 keV) ~ 3*E(-16) erg cm(-2) s(-1) - about 20 times as deep as current wide-area surveys. At the same time, we plan for ChaMP to cover much larger areas ( ~ 7 degrees(2) per year) than current deep surveys. For the nominal 5 year length of the project, we expect to identify about 2000 high galactic latitude serendipitous X-ray sources per year, of which as many as 80% may be AGN. The broader (0.2-8keV) spectral range of Chandra will detect a much larger fraction of obscured AGN than in previous large-scale X-ray-selected samples. The detection of extended X-ray emission will immediately signal the presence of a group or cluster of galaxies. ChaMP should yield a sample of over 200 distant clusters of galaxies in the critical redshift range z ~ 0.2-1, which will be used for studies of cosmology and cluster evolution. A companion galactic plane pilot study will search efficiently for CVs, LMXBs and X-ray novae.
- Publication:
-
AAS/High Energy Astrophysics Division #4
- Pub Date:
- April 1999
- Bibcode:
- 1999HEAD....4.0602G