BATSE observations of the Piccinotti sample of active galactic nuclei

Citation
A. Malizia et al., BATSE observations of the Piccinotti sample of active galactic nuclei, ASTROPHYS J, 519(2), 1999, pp. 637-641
Citations number
41
Categorie Soggetti
Space Sciences
Journal title
ASTROPHYSICAL JOURNAL
ISSN journal
0004637X → ACNP
Volume
519
Issue
2
Year of publication
1999
Part
1
Pages
637 - 641
Database
ISI
SICI code
0004-637X(19990710)519:2<637:BOOTPS>2.0.ZU;2-L
Abstract
BATSE Earth-occultation data have been used to search for emission in the 2 0-100 keV band from all sources in the Piccinotti sample, which represents the only complete 2-10 keV survey to date of the extragalactic sky down to a limiting flux of 3.1 x 10(-11) ergs cm(-2) s(-1). Nearly 4 yr of observat ions have been analyzed to reach a 5 sigma sensitivity level of about 7.8 x 10(-11) ergs cm(-2) s(-1) in the band considered. Of the 36 sources in the sample:, 14 have been detected above the 5 sigma confidence level, while m arginal detection (3 less than or equal to sigma less than or equal to 5) c an be claimed for 13 sources; for nine objects 2 sigma upper limits are rep orted. A comparison of BATSE results with data at higher energies is used t o estimate the robustness of our data analysis: while the detection level o f each source is reliable, the flux measurement maybe overestimated in some sources by as much as 35%, probably because of incomplete data cleaning. C omparison of BATSE fluxes with X-ray fluxes obtained in the 2-10 keV range and averaged over years indicates that a canonical power law of photon inde x 1.7 gives a good description of the broadband spectra of bright active ga lactic nuclei (AGNs) and that spectral breaks preferentially occur above 10 0 keV.