A search for dark matter in Triangulum II with the MAGIC telescopes
A search for dark matter in Triangulum II with the MAGIC telescopes
复制标题
使用 MAGIC 望远镜寻找三角座 II 中的暗物质
DOI：
10.1016/j.dark.2020.100529
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发表时间：
2020
影响因子：
5.5
通讯作者：
Acciari V. A. et al.
中科院分区：
文献类型：
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作者：
Masatsugu Nagai;Ryo Yoshida;Tatsuki Yamada;Taira Tabakoya;Christoph E. Nebel;Satoshi Yamasaki;Toshiharu Makino;Tsubasa Matsumoto;Takao Inokuma and Norio Tokuda;Acciari V. A. et al.
我们展示了2016年8月至2017年8月期间使用MAGIC望远镜对矮球状卫星候选人三角座II进行的62.4小时高质量数据的极高能量观测的第一个结果。我们没有发现在三角座II的方向上的伽马射线过剩，和上限的微分和积分的伽马射线通量。目前，三角座II的运动学受到很大的不确定性的影响，导致在确定其暗物质晕属性时存在偏差。利用已知矮球状星系湮灭J因子与日心距离之间的比例关系，我们估计三角座II的WIMP暗物质湮灭J因子log [Jann（0.5 μ m）/GeV 2 cm− 5]= 19.35±0.37。我们还得到了暗物质密度分布依赖于银河系大小的暗物质晕的模拟结果。我们得到95%的置信水平限制的热平均湮没截面的WIMP湮没到各种标准模型通道。最严格的极限是在τ+ τ−终态下得到的，其中不包括低至<$σannv <$= 3.05× 10− 24 cm 3 s− 1的湮灭截面。
We present the first results from very-high-energy observations of the dwarf spheroidal satellite candidate Triangulum II with the MAGIC telescopes from 62.4 hours of good-quality data taken between August 2016 and August 2017. We find no gamma-ray excess in the direction of Triangulum II, and upper limits on both the differential and integral gamma-ray flux are presented. Currently, the kinematics of Triangulum II are affected by large uncertainties leading to a bias in the determination of the properties of its dark matter halo. Using a scaling relation between the annihilation J-factor and heliocentric distance of well-known dwarf spheroidal galaxies, we estimate an annihilation J-factor for Triangulum II for WIMP dark matter of log [Jann (0.5∘)/GeV2 cm− 5]= 19.35±0.37. We also derive a dark matter density profile for the object relying on results from resolved simulations of Milky Way sized dark matter halos. We obtain 95% confidence-level limits on the thermally averaged annihilation cross section for WIMP annihilation into various Standard Model channels. The most stringent limits are obtained in the τ+ τ− final state, where a cross section for annihilation down to⟨ σannv⟩= 3.05× 10− 24 cm3 s− 1 is excluded.