A broadband microwave burst produced by electron beams
文献类型：期刊论文
| 作者 | Altyntsev, A. T.1,2; Fleishman, G. D.3,4,5; Huang, G. -L.1; Melnikov, V. F.6 |
| 刊名 | ASTROPHYSICAL JOURNAL
 |
| 出版日期 | 2008-04-20 |
| 卷号 | 677期号:2页码:1367-1377 |
| 关键词 | acceleration of particles Sun : flares Sun : radio radiation Sun : X-rays, gamma |
| ISSN号 | 0004-637X |
| 英文摘要 | The theoretical and experimental study of fast electron beams attracts much attention in astrophysics and the laboratory. In the case of solar flares, the problem of reliable beam detection and diagnostics is of exceptional importance. This paper explores the fact that electron beams moving obliquely to the magnetic field or along the field with some angular scatter around the beam's propagation direction can generate microwave continuum bursts through the gyrosynchrotron mechanism. The characteristics of the microwave bursts produced by beams differ from those in the case of isotropic or loss-cone distributions, which suggests a new quantitative diagnostic for beams in the solar corona. To demonstrate the potential of this tool, we analyze a radio burst that occurred during an impulsive class 1B/M6.7 flare on 2001 March 10 (NOAA AR 9368; N27 degrees, W42 degrees). Based on detailed analysis of the spectral, temporal, and spatial relationships, we obtain firm evidence that the microwave continuum burst was produced by electron beams. We develop and apply a new forward-fitting algorithm based on the exact gyrosynchrotron formulae and employing both total-power and polarization measurements to solve the inverse problem of the beam diagnostics. The burst is found to have been generated by an oblique beam in a region of reasonably strong magnetic field (similar to 200-300 G) and observed at a quasi-transverse viewing angle. We find that the lifetime of the emitting electrons in the radio source was relatively short, tau(l) approximate to 0.5 s, consistent with a single reflection of the electrons from a magnetic mirror at the footpoint with the stronger magnetic field. We discuss the implications of these findings for electron acceleration in flares and beam diagnostics. |
| 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] | SOLAR RADIO-TELESCOPE ; GYROSYNCHROTRON RADIATION ; MAGNETOACTIVE PLASMA ; INFRARED CONTINUUM ; THERMAL ELECTRONS ; SPATIAL STRUCTURE ; IMPULSIVE FLARE ; MARCH 10 ; EMISSION ; RAY |
| 收录类别 | SCI |
| 语种 | 英语 |
| WOS记录号 | WOS:000254898000046 |
| 公开日期 | 2011-12-30 |
| 源URL | [http://159.226.72.40/handle/332002/2029]  |
| 专题 | 紫金山天文台_太阳活动的多波段观测研究团组 |
| 作者单位 | 1.Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Peoples R China 2.Inst Solar Terr Phys, Irkutsk 664033, Russia 3.New Jersey Inst Technol, Dept Phys, Newark, NJ 07102 USA 4.New Jersey Inst Technol, Ctr Solar Terr Res, Newark, NJ 07102 USA 5.AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia 6.Radiophys Res Inst, Nizhnii Novgorod 603950, Russia |
| 推荐引用方式 GB/T 7714 | Altyntsev, A. T.,Fleishman, G. D.,Huang, G. -L.,et al. A broadband microwave burst produced by electron beams[J]. ASTROPHYSICAL JOURNAL,2008,677(2):1367-1377. |
| APA | Altyntsev, A. T.,Fleishman, G. D.,Huang, G. -L.,&Melnikov, V. F..(2008).A broadband microwave burst produced by electron beams.ASTROPHYSICAL JOURNAL,677(2),1367-1377. |
| MLA | Altyntsev, A. T.,et al."A broadband microwave burst produced by electron beams".ASTROPHYSICAL JOURNAL 677.2(2008):1367-1377. |
入库方式： OAI收割
来源：紫金山天文台
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。