2004/08/10 by M. G. Revnivtsev, E. M. Churazov, S. Yu. Sazonov +6 · 3 citations
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Star Formation Studies #X-ray Spectroscopy and Fluorescence Analysis #astro-ph
paper · pdf · doi:10.1051/0004-6361:200400064
published as Astron.Astrophys. 425 (2004) L49-L52 · 5 pages, 3 fugures. Submmitted to A&A Letters. Version with original quality figures can be taken from http://integral.rssi.ru/~mikej/sgr_aa.ps.gz
arxiv created 2004/08/10 · openalex publication_date 2004/09/28 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report the association of the recently discovered hard X-ray source IGR J17475-2822 with the giant molecular cloud Sgr B2 in the Galactic Center region. The broad band (3–200 keV) spectrum of the source constructed from data of different observatories strongly supports the idea that the X-ray emission of Sgr B2 is Compton scattered and reprocessed radiation emitted in the past by the Sgr A source. We conclude that 300–400 years ago Sgr A was a low luminosity ( erg s-1 at 2–200 keV) AGN with a characteristic hard X-ray spectrum (photon index ). We estimate the mass and iron abundance of the Sgr B2 scattering gas at and 1.9 solar, respectively (where r is the radius of the cloud).