The Burst and Transient Source Experiment (BATSE) Earth Occultation Catalog of Low‐Energy Gamma‐Ray Sources

Autor: B. A. Harmon, Mark H. Finger, J. E. Grindlay, Valerie Connaughton, Bradley M. Peterson, Gerald J. Fishman, Colleen A. Wilson, Didier Barret, W. Henze, Chris Shrader, M. Sahi, William S. Paciesas, M. L. McCollough
Rok vydání: 2004
Předmět:
Zdroj: The Astrophysical Journal Supplement Series. 154:585-622
ISSN: 1538-4365
0067-0049
DOI: 10.1086/421940
Popis: The Burst and Transient Source Experiment (BATSE), aboard the Compton Gamma Ray Observatory (CGRO), provided a record of the low-energy gamma-ray sky (20-1000 keV) between 1991 April and 2000 May (9.1y). Using the Earth Occultation Technique to extract flux information, a catalog of sources using data from the BATSE large area detectors has been prepared. The first part of the catalog consists of results from the monitoring of 58 sources, mostly Galactic. For these sources, we have included tables of flux and spectral data, and outburst times for transients. Light curves (or flux histories) have been placed on the world wide web. We then performed a deep-sampling of 179 objects (including the aforementioned 58 objects) combining data from the entire 9.1y BATSE dataset. Source types considered were primarily accreting binaries, but a small number of representative active galaxies, X-ray-emitting stars, and supernova remnants were also included. The deep sample results include definite detections of 83 objects and possible detections of 36 additional objects. The definite detections spanned three classes of sources: accreting black hole and neutron star binaries, active galaxies and supernova remnants. Flux data for the deep sample are presented in four energy bands: 20-40, 40-70, 70-160, and 160-430 keV. The limiting average flux level (9.1 y) for the sample varies from 3.5 to 20 mCrab (5 sigma) between 20 and 430 keV, depending on systematic error, which in turn is primarily dependent on the sky location. To strengthen the credibility of detection of weaker sources (5-25 mCrab), we generated Earth occultation images, searched for periodic behavior using FFT and epoch folding methods, and critically evaluated the energy-dependent emission in the four flux bands.
Comment: 64 pages, 17 figures, abstract abridged, Accepted by ApJS
Databáze: OpenAIRE