Advanced search for the extension of unresolved TeV sources with H.E.S.S.: First measurement of the extension of the Crab nebula at TeV energies
Advanced search for the extension of unresolved TeV sources with H.E.S.S.: First measurement of the extension of the Crab nebula at TeV energies
复制标题
使用 H.E.S.S. 对未解决的 TeV 源的扩展进行高级搜索：首次测量 TeV 能量下的蟹状星云的扩展
DOI：
10.22323/1.301.0676
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
R. Parsons
中科院分区：
文献类型：
--
作者：
M. Holler;D. Berge;J. Hahn;D. Khangulyan;R. Parsons
目前成像大气切伦科夫望远镜的分辨率仅限于几角分的尺度。在甚高能（VHE; E > 100 GeV）伽马射线状态中，与仪器分辨率相当或更小的源尺寸的测量通常受到统计数据的限制，特别是受到仪器特征的不确定性的限制点扩散函数（PSF）。PSF随观测和仪器条件变化很大，需要对这些条件进行随时间变化的模拟。采用这种模拟，我们大大提高了我们对H.E.S.S.的理解。PSF和现在能够探测远低于一弧分尺度的源扩展。我们提出的结果，这种新的方法应用于已知的VHE伽马射线源，并显示这如何使我们能够揭示第一次在TeV的伽马射线能量的蟹状星云的扩展，假设高斯源形状的宽度为52弧秒。
The resolution power of current Imaging Atmospheric Cherenkov Telescopes is presently restricted to scales of a few arcminutes. In the very high-energy (VHE; E > 100 GeV) gamma-ray regime, the measurement of source sizes that are comparable to or smaller than the resolution of the instrument is usually limited by statistics and in particular by the uncertainties in the characterisation of the instrument Point Spread Function (PSF). The PSF varies strongly with observation and instrument conditions, demanding time-dependent simulations of these conditions. Employing such simulations, we substantially improve our understanding of the H.E.S.S. PSF and are now able to probe source extensions well below one arcminute scale. We present the results of this new approach applied to known VHE gamma-ray sources and show how this enables us to reveal for the first time the extension of the Crab nebula at TeV gamma-ray energies, with a width of 52 arcsec assuming a Gaussian source shape.