论文标题
建模银河系非常高的能量$γ$ ray源人群
Modelling the Galactic very-high-energy $γ$-ray source population
论文作者
论文摘要
高能立体镜系统（H.E.S.S.）银河飞机调查（HGPS）迄今为止是非常高能的银河$γ$ - 雷来源的最全面的人口普查（vhe; $ 100 \，\，\，\ Mathrm {gev}由于这项调查的敏感性有限，这78个检测到$γ$ ray的来源仅包含整个总体的小且有偏见的子样本。尽管如此，数值建模仍使我们能够根据该样本以银河系的方式研究VHE $γ$ ray源人群。在这项工作中，比较了几种方位对称和螺旋臂模型的空间源分布。种群的光度和半径函数来自HGPS数据集的源特性，并校正HGPS的灵敏度偏置。基于这些模型，模拟了VHE源群体，并根据HGPS将可检测到的源子集与HGPS源进行比较。亮度和半径功能的幂律指数确定为亮度的$ -1.6 $和$ -1.9 $，半径为$ -1.1 $和$ -1.6 $。没有银河棒的四臂螺旋结构之后的方位对称分布和分布很好地描述了HGPS数据。预计银河系来源的总数在800到7000范围内，总发光度和通量为$（1.6-6.3）\ CDOT 10^{36} $ 〜ph〜s $^s $^{ - 1} $ and $（3-15）和$（3-15）和$（3-15） 分别。根据模型，HGPS样本占扫描地区人口排放的$（68-87）\％$。这表明未解决的来源代表了HGP中可测量的弥漫发射的关键组成部分。随着Cherenkov望远镜阵列的灵敏度的预见跳跃，预计可检测到的来源的数量将增加在5-9之间。
The High Energy Stereoscopic System (H.E.S.S.) Galactic plane survey (HGPS) is to date the most comprehensive census of Galactic $γ$-ray sources at very high energies (VHE; $100\,\mathrm{GeV}\leq E\leq 100\,\mathrm{TeV}$). As a consequence of the limited sensitivity of this survey, the 78 detected $γ$-ray sources comprise only a small and biased subsample of the overall population. Still, numerical modelling allows us to study the VHE $γ$-ray source population in the Milky Way based on this sample. In this work, several azimuth-symmetric and spiral-arm models are compared for spatial source distribution. The luminosity and radius function of the population are derived from the source properties of the HGPS data set and are corrected for the sensitivity bias of the HGPS. Based on these models, VHE source populations are simulated and the subsets of sources detectable according to the HGPS are compared with HGPS sources. The power-law indices of luminosity and radius functions are determined to range between $-1.6$ and $-1.9$ for luminosity and $-1.1$ and $-1.6$ for radius. Azimuth-symmetric distributions and a distribution following a four-arm spiral structure without Galactic bar describe the HGPS data reasonably well. The total number of Galactic VHE sources is predicted to be in the range from 800 to 7000 with a total luminosity and flux of $(1.6-6.3) \cdot 10^{36}$~ph~s$^{-1}$ and $(3-15) \cdot 10^{-10}$~ph~cm$^{-2}$~s$^{-1}$, respectively. Depending on the model, the HGPS sample accounts for $(68-87)\%$ of the emission of the population in the scanned region. This suggests that unresolved sources represent a critical component of the diffuse emission measurable in the HGPS. With the foreseen jump in sensitivity of the Cherenkov Telescope Array, the number of detectable sources is predicted to increase by a factor between 5 - 9.
