@inproceedings{oai:jaxa.repo.nii.ac.jp:00005292,
 author = {Gandhi, Poshak},
 book = {宇宙航空研究開発機構特別資料, JAXA Special Publication: Astrophysics with All-Sky X-Ray observations: 3rd International MAXI Workshop},
 month = {Feb},
 note = {Astrophysics with All-Sky X-Ray observations: 3rd International MAXI Workshop (RIKEN, 10-12 June 2008), Light bending due to strong gravity has recently been invoked to explain variability and flux correlations between different bands in some accreting black holes. A characteristic feature of light bending is reflection-dominated spectra, especially if photon sources lie in the deepest parts of the gravitational potential within a few gravitational radii of the event horizon. We use the spectrum of the hard X-ray background in order to constrain the prevalence of such reflection-dominated sources. We first explore the broad-band properties of realistic spectra that incorporate light bending and then use these spectra, in conjunction with the observed 2 - 10 keV AGN luminosity functions in order to predict the hard X-ray background spectrum over 3 - 100 keV, and provide limits on the fraction of reflection-dominated sources, dependent on the flare height. Our results allow for a cosmologically significant fraction of sources that incorporate strong light bending. The luminosity function based on intrinsic flare luminosities is derived. We discuss prospects for missions such as NeXT and Simbol-X that can image such sources as well as confirm the precise spectral shape of the background near its peak, important for constraining the universal relevance of light bending., Physical characteristics: Original contains color illustrations, 資料番号: AA0064306053, レポート番号: JAXA-SP-08-014E},
 pages = {264--269},
 publisher = {宇宙航空研究開発機構, Japan Aerospace Exploration Agency (JAXA)},
 title = {Light bending and the hard X-ray background},
 volume = {JAXA-SP-08-014E},
 year = {2009}
}