THE VARIABILITY OF SAGITTARIUS A* AT 3 MILLIMETER
文献类型：期刊论文
| 作者 | Li, Juan1,2 ; Shen, Zhi-Qiang1; Miyazaki, Atsushi3; Huang, Lei1,4,7; Sault, R. J.5; Miyoshi, Makoto3; Tsuboi, Masato6; Tsutsumi, Takahiro3
|
| 刊名 | ASTROPHYSICAL JOURNAL
 |
| 出版日期 | 2009-07-20 |
| 卷号 | 700期号:1页码:417-425 |
| 关键词 | Galaxy: center techniques: interferometric |
| 英文摘要 | We have performed monitoring observations of the 3 mm flux density toward the Galactic center compact radio source Sagittarius A* (Sgr A*) with the Australia Telescope Compact Array since 2005 October. Careful calibrations of both elevation-dependent and time-dependent gains have enabled us to establish the variability behavior of Sgr A*. Sgr A* appeared to undergo a high and stable state in the 2006 June session, and a low and variable state in the 2006 August session. We report the results, with emphasis on two detected intraday variation events during its low states. One is on 2006 August 12 when Sgr A* exhibited a 33% fractional variation in about 2.5 hr. The other is on 2006 August 13 when two peaks separated by about 4 hr, with a maximum variation of 21% within 2 hr, were seen. The observed short timescale variations are discussed in light of two possible scenarios, i.e., the expanding plasmon model and the sub-Keplerian orbiting hot spot model. The fitting results indicate that for the adiabatically expanding plasmon model, the synchrotron cooling cannot be ignored, and a minimum mass-loss rate of 9.7 x 10(-10) M(circle dot) yr(-1) is obtained based on parameters derived for this modified expanding plasmon model. Simultaneous multiwavelength observation is crucial to our understanding of the physical origin of rapid radio variability in Sgr A*. |
| WOS标题词 | Science & Technology ; Physical Sciences |
| 学科主题 | 星系与宇宙学研究中心 |
| 类目[WOS] | Astronomy & Astrophysics |
| 研究领域[WOS] | Astronomy & Astrophysics |
| 关键词[WOS] | ADVECTION-DOMINATED ACCRETION ; SUPERMASSIVE BLACK-HOLE ; NEAR-INFRARED FLARES ; SGR-A ; X-RAY ; GALACTIC-CENTER ; FLARING ACTIVITY ; EMISSION ; FLOW ; WAVELENGTHS |
| 收录类别 | SCI |
| 语种 | 英语 |
| WOS记录号 | WOS:000267768900034 |
| 公开日期 | 2010-11-08 |
| 源URL | [http://119.78.226.72//handle/331011/12371]  |
| 专题 | 上海天文台_星系宇宙学重点实验室 |
| 作者单位 | 1.Chinese Acad Sci, Shanghai Astron Observ, Key Lab Res Galaxies & Cosmol, Shanghai 200030, Peoples R China 2.Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China 3.Natl Astron Observ Japan, Tokyo 1818588, Japan 4.Univ Sci & Technol China, Key Lab Res Galaxies & Cosmol, Hefei 230026, Peoples R China 5.Univ Melbourne, Sch Phys, Parkville, Vic 3052, Australia 6.Japan Aerosp Explorat Agcy, Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan 7.Acad Sinica, Inst Astron & Astrophys, Taipei 106, Taiwan |
| 推荐引用方式 GB/T 7714 | Li, Juan,Shen, Zhi-Qiang,Miyazaki, Atsushi,et al. THE VARIABILITY OF SAGITTARIUS A* AT 3 MILLIMETER[J]. ASTROPHYSICAL JOURNAL,2009,700(1):417-425. |
| APA | Li, Juan.,Shen, Zhi-Qiang.,Miyazaki, Atsushi.,Huang, Lei.,Sault, R. J..,...&Tsutsumi, Takahiro.(2009).THE VARIABILITY OF SAGITTARIUS A* AT 3 MILLIMETER.ASTROPHYSICAL JOURNAL,700(1),417-425. |
| MLA | Li, Juan,et al."THE VARIABILITY OF SAGITTARIUS A* AT 3 MILLIMETER".ASTROPHYSICAL JOURNAL 700.1(2009):417-425. |
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。