Spectral and spatial analysis of the dark matter subhalo candidates among Fermi Large Area Telescope unidentified sources
Spectral and spatial analysis of the dark matter subhalo candidates among Fermi Large Area Telescope unidentified sources
复制标题
费米大面积望远镜未识别源中暗物质子晕候选者的光谱和空间分析
DOI：
10.1088/1475-7516/2019/11/045
复制
发表时间：
2019
影响因子：
6.4
通讯作者：
N. Mirabal
中科院分区：
文献类型：
--
作者：
J. Coronado;M. S'anchez;M. D. Mauro;A. Aguirre;I. Ciucă;A. Domínguez;D. Kawata;N. Mirabal
费米-LAT 未识别源 (UNID) 已被证明是执行间接暗物质 (DM) 搜索的引人注目的目标。在之前的工作中，我们发现在 Fermi-LAT 目录（3FGL、2FHL 和 3FHL）的 1235 个 unID 中，只有 44 个是 DM subhalos 候选者。 We now implement a spectral analysis to test whether these remaining sources are compatible or not with DM origin.该分析是使用近 10 年的 Pass 8 Fermi-LAT 数据执行的。与其他更传统的天体物理来源相比，没有发现任何 unID 明显更喜欢DM引起的发射。为了区分脉冲星源和DM源，我们开发了一种基于源的光谱曲率、峰值能量及其检测意义的新方法。我们还寻找空间延伸，根据我们对 subhalo 种群的 N 体模拟研究，这可能是 DM 起源的暗示。此外，我们使用 Gaia DR2 数据来寻找与我们最好的 DM 子晕候选者潜在的恒星对应物，虽然没有找到可靠的关联，但其中之一与人马座流相一致。最后，先前对 DM 湮没截面的约束将更新为 unID 中剩余 DM 子晕候选者的新数量。我们的限制现在排除了 bb̄ 质量高达 10 GeV 和 τ+τ− 湮没通道质量高达 20 GeV 的典型热 WIMP，这样与从其他目标和探测器获得的质量一样敏感和互补。
Fermi-LAT unidentified sources (unIDs) have proven to be compelling targets for performing indirect dark matter (DM) searches. In a previous work, we found that among the 1235 unIDs in Fermi-LAT's catalogs (3FGL, 2FHL and 3FHL) only 44 of those are DM subhalos candidates. We now implement a spectral analysis to test whether these remaining sources are compatible or not with DM origin. This analysis is executed using almost 10 years of Pass 8 Fermi-LAT data. None of the unIDs are found to significantly prefer DM-induced emission compared to other, more conventional, astrophysical sources. In order to discriminate between pulsar and DM sources, we developed a new method which is based on the source's spectral curvature, peak energy, and its detection significance. We also look for spatial extension, which may be a hint for a DM origin according to our N-body simulation studies of the subhalo population. In addition, we used Gaia DR2 data to search for a potential stellar counterpart to our best DM subhalo candidates and, although no firm associations could be found, one of them coincides with the Sagittarius stream. Finally, previous constraints on the DM annihilation cross section are updated with the new number of remaining DM subhalo candidates among unIDs. Our limits now rule out canonical thermal WIMPs up to masses of 10 GeV for bb̄ and 20 GeV for τ+τ− annihilation channels, in this way being as sensitive and complementary to those obtained from other targets and probes.