arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1604.01769astro-ph.HEastro-ph.CO
收藏

微透镜作为类星体事件视界结构的可能探测

Microlensing as a possible probe of event-horizon structure in quasars

Mihai Tomozeiu, Irshad Mohammed, Manuel Rabold, Prasenjit Saha, Joachim Wambsganss

摘要:

在被星系透镜化的类星体中,点状图像有时会显示出尖锐且不相关的亮度变化(微透镜效应)。这些亮度变化与类星体最里面的区域通过透镜星系中恒星产生的复杂焦散图案有关。在本文中,我们研究的普遍性质的光学焦散是否可以使提取的形状信息的中央引擎的类星体。我们提出了一个玩具模型,一个新月形的源穿过一个折叠焦散。黑洞在吸积盘上的轮廓往往会产生近似新月形的源。当一个新月形的光源穿过一个折叠焦散时,产生的光变曲线与圆形光度分布或高斯光源的情况明显不同。只要有足够好的监测数据,除了一个简并度外,新月体的参数是可以恢复的。

英文摘要:

In quasars which are lensed by galaxies, the point-like images sometimes show sharp and uncorrelated brightness variations (microlensing). These brightness changes are associated with the innermost region of the quasar passing through a complicated pattern of caustics produced by the stars in the lensing galaxy. In this paper, we study whether the universal properties of optical caustics could enable extraction of shape information about the central engine of quasars. We present a toy model with a crescent-shaped source crossing a fold caustic. The silhouette of a black hole over an accretion disk tends to produce roughly crescent sources. When a crescent-shaped source crosses a fold caustic, the resulting light curve is noticeably different from the case of a circular luminosity profile or Gaussian source. With good enough monitoring data, the crescent parameters, apart from one degeneracy, can be recovered.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑