人马座A*事件视界附近动力学重要的磁场
高能天体物理现象
2020-09-15 v2
摘要
我们研究2018年7月28日GRAVITY仪器观测到的Sgr A*亮NIR耀发期间的时变线偏振。受观测天体测量与偏振特征时间演化的启发，我们以固定背景磁场几何中绕黑洞运动的致密区（'热斑'）偏振发射来解释数据。我们计算了广义相对论光线追踪模型网格，通过模拟仪器响应生成模拟观测，并将预测的偏振量直接与测量值比较。我们考虑了现已包含仪器随时间响应的改进仪器校准，并探索了多种理想化磁场构型。我们发现线偏振角在耀发期间旋转，与先前结果一致。热斑模型可解释观测到的线偏振演化。为匹配此次耀发的天体测量周期，近视界磁场需具显著极向分量，其关联于强且动力学重要的场。观测到的线偏振度小于模型预测值（）。发射很可能被束去偏振，表明耀发发射区解析了黑洞附近的磁场结构。
引用
@article{arxiv.2009.01859,
title = {Dynamically important magnetic fields near the event horizon of Sgr A*},
author = {GRAVITY Collaboration and A. Jiménez-Rosales and J. Dexter and F. Widmann and M. Bauböck and R. Abuter and A. Amorim and J. P. Berger and H. Bonnet and W. Brandner and Y. Clénet and P. T. de Zeeuw and A. Eckart and F. Eisenhauer and N. M. Förster Schreiber and P. Garcia and F. Gao and E. Gendron and R. Genzel and S. Gillessen and M. Habibi and X. Haubois and G. Heissel and T. Henning and S. Hippler and M. Horrobin and L. Jochum and L. Jocou and A. Kaufer and P. Kervella and S. Lacour and V. Lapeyrère and J. -B. Le Bouquin and P. Léna and M. Nowak and T. Ott and T. Paumard and K. Perraut and G. Perrin and O. Pfuhl and G. Rodríguez-Coira and J. Shangguan and S. Scheithauer and J. Stadler and O. Straub and C. Straubmeier and E. Sturm and L. J. Tacconi and F. Vincent and S. von Fellenberg and I. Waisberg and E. Wieprecht and E. Wiezorrek and J. Woillez and S. Yazici and G. Zins},
journal= {arXiv preprint arXiv:2009.01859},
year = {2020}
}
备注
13 pages, 14 figures, to be published in A&A