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CHANDRA/HETGS OBSERVATIONS OF THE BRIGHTEST FLARE SEEN FROM Sgr A*
文献类型：期刊论文
| 作者 | Nowak, M. A.1; Neilsen, J.1; Markoff, S. B.2; Baganoff, F. K.1; Porquet, D.3; Grosso, N.3; Levin, Y.4,5,6; Houck, J.1; Eckart, A.7; Falcke, H.8,9,10 |
| 刊名 | ASTROPHYSICAL JOURNAL
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| 出版日期 | 2012-11-10 |
| 卷号 | 759期号:2页码:95(5pp) |
| 关键词 | accretion, accretion disks black hole physics radiation mechanisms: non-thermal |
| ISSN号 | 0004-637X |
| 英文摘要 | Starting in 2012, we began an unprecedented observational program focused on the supermassive black hole in the center of our Galaxy, Sgr A*, utilizing the High Energy Transmission Grating Spectrometer (HETGS) instrument on the Chandra X-Ray Observatory. These observations will allow us to measure the quiescent X-ray spectra of Sgr A* for the first time at both high spatial and spectral resolution. The X-ray emission of Sgr A*, however, is known to flare roughly daily by factors of a few to ten times over quiescent emission levels, with rarer flares extending to factors of greater than 100 times quiescence. Here we report an observation performed on 2012 February 9 wherein we detected what are the highest peak flux and fluence flare ever observed from Sgr A*. The flare, which lasted for 5.6 ks and had a decidedly asymmetric profile with a faster decline than rise, achieved a mean absorbed 2-8 keV flux of (8.5 +/- 0.9) x 10(-12) erg cm(-2) s(-1). The peak flux was 2.5 times higher, and the total 2-10 keV emission of the event was approximately 10(39) erg. Only one other flare of comparable magnitude, but shorter duration, has been observed in Sgr A* by XMM-Newton in 2002 October. We perform spectral fits of this Chandra-observed flare and compare our results to the two brightest flares ever observed with XMM-Newton. We find good agreement among the fitted spectral slopes (Gamma similar to 2) and X-ray absorbing columns (N-H similar to 15 x 10(22) cm(-2)) for all three of these events, resolving prior differences (which are most likely due to the combined effects of pileup and spectral modeling) among Chandra and XMM-Newton observations of Sgr A* flares. We also discuss fits to the quiescent spectra of Sgr A*. |
| WOS标题词 | Science & Technology ; Physical Sciences |
| 学科主题 | Astronomy & Astrophysics |
| 类目[WOS] | Astronomy & Astrophysics |
| 研究领域[WOS] | Astronomy & Astrophysics |
| 关键词[WOS] | X-RAY FLARE ; SUPERMASSIVE BLACK-HOLE ; VARIABLE INFRARED-EMISSION ; ACTIVE GALACTIC NUCLEI ; SAGITTARIUS-A ; XMM-NEWTON ; INTERSTELLAR-MEDIUM ; FUNDAMENTAL PLANE ; CROSS-SECTIONS ; GAMMA-RAY |
| 收录类别 | SCI |
| 语种 | 英语 |
| WOS记录号 | WOS:000310911300018 |
| 公开日期 | 2013-01-31 |
| 源URL | [http://libir.pmo.ac.cn/handle/332002/7972]  |
| 专题 | 紫金山天文台_毫米波和亚毫米波技术实验室 |
| 作者单位 | 1.MIT, Kavli Inst Astrophys, Cambridge, MA 02139 USA 2.Univ Amsterdam, Astron Inst Anton Pannekoek, Amsterdam, Netherlands 3.Univ Strasbourg, CNRS, UMR 7550, Observ Astron Strasbourg, F-67000 Strasbourg, France 4.Monash Univ, Sch Phys, Clayton, Vic 3800, Australia 5.Monash Univ, CSPA, Clayton, Vic 3800, Australia 6.Leiden Univ, Leiden Observ, NL-2300 RA Leiden, Netherlands 7.Univ Cologne, Inst Phys, D-50937 Cologne, Germany 8.Radboud Univ Nijmegen, IMAPP, Dept Astrophys, NL-6500 GL Nijmegen, Netherlands 9.ASTRON, NL-7990 AA Dwingeloo, Netherlands 10.Max Planck Inst Radioastron, D-53121 Bonn, Germany |
| 推荐引用方式 GB/T 7714 | Nowak, M. A.,Neilsen, J.,Markoff, S. B.,et al. CHANDRA/HETGS OBSERVATIONS OF THE BRIGHTEST FLARE SEEN FROM Sgr A*[J]. ASTROPHYSICAL JOURNAL,2012,759(2):95(5pp). |
| APA | Nowak, M. A..,Neilsen, J..,Markoff, S. B..,Baganoff, F. K..,Porquet, D..,...&Wang, Q. D..(2012).CHANDRA/HETGS OBSERVATIONS OF THE BRIGHTEST FLARE SEEN FROM Sgr A*.ASTROPHYSICAL JOURNAL,759(2),95(5pp). |
| MLA | Nowak, M. A.,et al."CHANDRA/HETGS OBSERVATIONS OF THE BRIGHTEST FLARE SEEN FROM Sgr A*".ASTROPHYSICAL JOURNAL 759.2(2012):95(5pp). |
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来源：紫金山天文台
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