The NuSTAR Extragalactic Surveys: Number Counts and Directly Resolved Fraction of the Cosmic X-ray Background
Abstract
NuSTAR has carried out a multi-tiered extragalactic survey program, consisting of deep (~400 ks) observations of the ~0.3 deg2 Extended Chandra Deep Field South (ECDFS) and ~0.25 deg2 Extended Groth Strip (EGS), medium depth (~100 ks) observations of the 2 deg2 COSMOS field, and a serendipitous program covering >7 deg2 to a range of depths. I present measurements of the intrinsic number counts as a function of flux (logN-logS) from the combination of the three survey elements, including direct measurements of the number counts at 8-24 keV energies that reach two orders of magnitudes fainter in flux than previous studies. I will also show how NuSTAR has directly resolved >30% of the Cosmic X-ray background at 8-24 keV energies -- a factor ~30 times more than previous >10 keV observatories.
- Publication:
-
American Astronomical Society Meeting Abstracts #225
- Pub Date:
- January 2015
- Bibcode:
- 2015AAS...22522208A