Effect of the uncertainty in the hadronic interaction models on the estimation of the sensitivity of the Cherenkov telescope array
Effect of the uncertainty in the hadronic interaction models on the estimation of the sensitivity of the Cherenkov telescope array
复制标题
DOI：
10.1088/1361-6471/abfce0
复制
发表时间：
2021-05
期刊：
影响因子：
--
通讯作者：
M. Ohishi;L. Arbeletche;V. de Souza;G. Maier;K. Bernlöhr;A. M. Olaizola;J. Bregeon;L. Arrabito;T. Yoshikoshi
中科院分区：
文献类型：
--
作者：
M. Ohishi;L. Arbeletche;V. de Souza;G. Maier;K. Bernlöhr;A. M. Olaizola;J. Bregeon;L. Arrabito;T. Yoshikoshi
成像大气切伦科夫望远镜（IACTs）是能量超过数十GeV的宇宙伽马射线的地面间接探测器。IACT中γ射线观测的主要背景是宇宙射线带电粒子。拒绝这些背景的能力是决定IACT系统的伽马射线灵敏度的最重要因素。蒙特卡罗模拟被用来估计剩余的本底率和灵敏度的系统在设计和施工阶段。宇宙射线与空气中的原子核的高能强子相互作用的建模中的unexplained传播到剩余背景率的估计，随后到估计的仪器灵敏度。我们调查的影响，在目前的强子相互作用模型的差异估计的γ射线灵敏度的切伦科夫望远镜阵列使用四个相互作用模型（QGSJET-II-03，QGSJET-II-04，EPOS-LHC，和SIBYLL2.3c）实现的空气淋浴模拟工具CORSIKA。在模型之间观察到QGSJET-II-03的背景速率变化高达2倍，这主要是由于生产谱的差异。这些导致在1 - 30 TeV区域中估计的伽马射线灵敏度的差异约为30%，假设对伽马射线点状源进行50小时的观测。所给出的结果也表明，IACTs在强子相互作用模型的验证中具有显著的能力。
Imaging Atmospheric Cherenkov Telescopes (IACTs) are ground-based indirect detectors for cosmic gamma rays with energies above tens of GeV. The major backgrounds for gamma-ray observations in IACTs are cosmic-ray charged particles. The capability to reject these backgrounds is the most important factor determining the gamma-ray sensitivity of IACT systems. Monte Carlo simulations are used to estimate the residual background rates and sensitivity of the systems during the design and construction phase. Uncertainties in the modeling of high-energy hadronic interactions of cosmic rays with nuclei in the air propagate into the estimates of residual background rates and subsequently into the estimated instrument sensitivity. We investigate the influence of the difference in the current hadronic interaction models on the estimated gamma-ray sensitivity of the Cherenkov Telescope Array using four interaction models (QGSJET-II-03, QGSJET-II-04, EPOS-LHC, and SIBYLL2.3c) implemented in the air shower simulation tool CORSIKA. Variations in background rates of up to a factor 2 with respect to QGSJET-II-03 are observed between the models, mainly due to differences in the $\pi^0$ production spectrum. These lead to ~30% differences in the estimated gamma-ray sensitivity in the 1 - 30 TeV region, assuming a 50-hour observation of a gamma-ray point-like source. The presented results also show that IACTs have a significant capability in the verification of hadronic interaction models.