热门
Intrinsic size of Sagittarius A*: 72 Schwarzschild radii
文献类型：期刊论文
| 作者 | Lo, KY; Shen, ZQ; Zhao, JH; Ho, PTP |
| 刊名 | ASTROPHYSICAL JOURNAL
 |
| 出版日期 | 1998-11-20 |
| 卷号 | 508期号:1页码:L61-L64 |
| 关键词 | galaxies : active Galaxy : center scattering |
| 英文摘要 | Recent proper motion studies of stars at the very center of the Galaxy strongly suggest that Sagittarius A*, the compact nonthermal radio source at the Galactic center, is a 2.5 x 10(6) M. black hole. By means of near-simultaneous multiwavelength Very Long Baseline Array measurements, we determine for the first time the intrinsic size and shape of Sgr A* to be 72 R-sc(star) by less than 20 R-sc(star), with the major axis oriented essentially north-south, where R-sc(star)(= 7.5 x 10(11) cm) is the Schwarzschild radius for a 2.5 x 10(6) M. black hole. Contrary to previous expectation that the intrinsic structure of Sgr A* is observable only at lambda less than or equal to 1 mm, we can discern the intrinsic source size at lambda = 7 mm because (1) the scattering size along the minor axis is half that along the major axis and (2) the near-simultaneous multiwavelength mapping of Sgr A* with the same interferometer makes it possible to extrapolate precisely the minor axis scattering angle at lambda = 7 mm. The intrinsic size and shape place direct constraints on the various emission models for Sgr A*. In particular, the advection-dominated accretion flow model may have to incorporate a radio jet in order to account for the structure of Sgr A*. |
| WOS标题词 | Science & Technology ; Physical Sciences |
| 类目[WOS] | Astronomy & Astrophysics |
| 研究领域[WOS] | Astronomy & Astrophysics |
| 关键词[WOS] | STELLAR PROPER MOTIONS ; SOURCE SGR-A ; GALACTIC-CENTER ; SCINTILLATION ; TURBULENCE ; LIMIT ; MODEL ; VLBI |
| 收录类别 | SCI |
| 语种 | 英语 |
| WOS记录号 | WOS:000077780300015 |
| 源URL | [http://119.78.226.72/handle/331011/28136]  |
| 专题 | 上海天文台_星系宇宙学重点实验室 |
| 作者单位 | 1.Acad Sinica, Inst Astron & Astrophys, Taipei 115, Taiwan 2.Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA 3.Acad Sinica, Shanghai Observ, Shanghai 200030, Peoples R China |
| 推荐引用方式 GB/T 7714 | Lo, KY,Shen, ZQ,Zhao, JH,et al. Intrinsic size of Sagittarius A*: 72 Schwarzschild radii[J]. ASTROPHYSICAL JOURNAL,1998,508(1):L61-L64. |
| APA | Lo, KY,Shen, ZQ,Zhao, JH,&Ho, PTP.(1998).Intrinsic size of Sagittarius A*: 72 Schwarzschild radii.ASTROPHYSICAL JOURNAL,508(1),L61-L64. |
| MLA | Lo, KY,et al."Intrinsic size of Sagittarius A*: 72 Schwarzschild radii".ASTROPHYSICAL JOURNAL 508.1(1998):L61-L64. |
入库方式： OAI收割
来源：上海天文台
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。