Prospects for the detection of high-energy (E > 25 GeV) Fermi pulsars with the Cherenkov Telescope Array
Prospects for the detection of high-energy (E > 25 GeV) Fermi pulsars with the Cherenkov Telescope Array
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DOI：
10.1093/mnras/stx1582
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发表时间：
2017-06
影响因子：
4.8
通讯作者：
A. Burtovoi;A. Burtovoi;T. Saito;L. Zampieri;T. Hassan
中科院分区：
文献类型：
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作者：
A. Burtovoi;A. Burtovoi;T. Saito;L. Zampieri;T. Hassan
自 2008 年以来，费米大面积望远镜 (LAT) 发现了大约 160 颗伽马射线脉冲星。其中能量最高的 12 个发射量超过 25 GeV 的天体，是当前和未来几十 GeV 以上的大气成像切伦科夫望远镜探测的合适候选者。我们对这些高能脉冲星的费米-LAT 数据进行分析，以确定是否可以使用切伦科夫望远镜阵列 (CTA) 探测到此类物体。我们的目标是预测 CTA 点源检测的重要性。我们分析了 5 年的费米-LAT 数据，用幂律函数拟合能量 E>10 GeV 下每个脉冲星的光谱。假设没有光谱截止，我们将所得光谱外推到非常高的能量范围（VHE，E>0.1 TeV），并使用 ctools 软件包模拟所有 12 颗脉冲星的 CTA 观测。使用不同的分析工具，独立计算每个脉冲星的单独的 CTA 灵敏度曲线，并与 ctools 结果进行交叉检查。我们的模拟结果是在 50 小时内对多达 8 颗脉冲星进行了显着的 CTA 检测。利用 CTA 对能量最高的费米脉冲星进行观测将揭示脉冲星高能发射的本质，澄清蟹状脉冲星光谱中检测到的 VHE 发射是否也存在于其他伽马射线脉冲星中。
Around 160 gamma-ray pulsars were discovered by the Fermi Large Area Telescope (LAT) since 2008. The most energetic of them, 12 objects with emission above 25 GeV, are suitable candidates for the detection with the current and future Imaging Atmospheric Cherenkov Telescopes above few tens of GeV. We perform an analysis of the Fermi-LAT data of these high-energy pulsars in order to determine if such objects can be detected with the Cherenkov Telescope Array (CTA). Our goal is to forecast the significance of their point source detection with CTA. We analyze 5 years of the Fermi-LAT data fitting the spectra of each pulsar at energies E>10 GeV with a power-law function. Assuming no spectral cut-off, we extrapolate the resulting spectra to the very high energy range (VHE, E>0.1 TeV) and simulate CTA observations of all 12 pulsars with the ctools software package. Using different analysis tools, individual CTA sensitivity curves are independently calculated for each pulsar and cross-checked with the ctools results. Our simulations result in significant CTA detections of up to 8 pulsars in 50 h. Observations of the most energetic Fermi pulsars with CTA will shed light on the nature of the high-energy emission of pulsars, clarifying whether the VHE emission detected in the Crab pulsar spectrum is present also in other gamma-ray pulsars.