| 报告题目： |
Nonthermal Processes of Fast Outflows from Centaurus A, M87, and G1.9+0.3 |
| 报告人： |
孙晓娜 博士 |
| 报告人单位： |
南京大学 |
| 报告时间： |
2019年10月22日 (星期二)上午10:00 |
| 报告地点： |
东七楼，四楼427 |
| 邀请单位： |
粒子与天体物理研究所 |
| 报告摘要： |
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Outflows are ubiquitous phenomena in the universe. They have been widely observed in both Galactic and extragalactic objects. Here I report three individual sources. Firstly, we analyze the high energy gamma-ray data of Fermi-LAT on the giant lobes of Centaurus A. We utilize for the first time the Planck observations to derive the fluxes of the lobes. The multiwave-length SEDs reveal a possible leptonic-hadronic origin of the non-thermal emission. Secondly, we analyze Chandra observations of the M87 jet with a total exposure time of 1500 kiloseconds to explore the X-ray emission characteristics along the jet. The variabilsities of the nucleus and HST-1, as well as the photon spectra for all knots are investigated. Fitting the radio to X-ray SEDs assuming a synchrotron origin, we show that a broken power-law electron spectrum allows a satisfactory description of the SEDs for most knots except for B, C and D, for which an additional component is needed. We discuss the implications and suggest that a stratified jet model may account for the differences. Finally, we derive the energy distribution of ultrarelativistic electron in G1.9+0.3, which is the youngest known SNR in the Galaxy, under the assumption that the detected X-ray with Chandra and NuSTAR are of entirely synchrotron origin. The electron acceleration is found to be an order of magnitude slower than the maximum rate provided by the shock acceleration in the nominal Bohm diffusion regime. We discuss the resultant implications in the context of contribution of SNRs to the Galactic Cosmic Rays at PeV energies. |
| 报告人简介： |
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主要从事活动星系核的多波段数据分析和理论研究。
09/2011 - 06/2014 广西大学 硕士研究生。
10/2014 - 12/2017 海德堡大学&马克斯-普朗克核物理研究所，博士研究生。
03/2018 – 现在， 南京大学 博士后。 |
