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arXiv 1012.2292astro-ph.HE
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用费米LAT间接寻找银河系中心的暗物质

The Indirect Search for Dark Matter from the centre of the Galaxy with the Fermi LAT

A. Morselli, B. Canadas, V. Vitale

摘要:

暗物质(DM)约占宇宙的25%,而重子仅占4%。DM可以合理地假设是由粒子组成的,许多理论(超对称性,宇宙额外维度等)。预测弱相互作用大质量粒子(WIMPs)作为弱尺度下的自然DM候选者。WIMP的自湮灭(或衰变)可能会通过强子化或终态辐射产生次级伽马射线。自2008年发射以来,费米伽马射线太空望远镜上的大面积望远镜已经探测到了迄今为止最大数量的伽马射线,在20 MeV至300 GeV的能量范围内,允许对DM进行非常灵敏的间接实验搜索(通过高能伽马射线)。DM形成了巨大的引力束缚结构,晕,它可以容纳整个星系,如银河系。尽管可能存在非常大的密度增强,但在晕的中心部分的DM分布在实验上是未知的。由于次级伽马射线的产生对WIMP密度非常敏感,因此可以从预期密度最大的区域进行非常有效的搜索。因此,DM晕N体模拟提供的信息是至关重要的。来自DM湮灭的最大伽马射线信号预计来自银河系中心。在同一区域,明亮的离散源和宇宙射线与星际气体和光子场相互作用产生了大的伽马射线背景。在这里,我们报告了从银河系中心(GC)间接搜索DM的最新情况。

英文摘要:

Dark matter (DM) constitutes around a 25% of the Universe, while baryons only a 4%. DM can be reasonably assumed to be made of particles, and many theories (Super-symmetry, Universal Extra Dimensions, etc.) predict Weakly Interacting Massive Particles (WIMPs) as natural DM candidates at the weak scale. Self-annihilation (or decay) of WIMPs might produce secondary gamma-rays, via hadronization or as final state radiation. Since its launch in the 2008, the Large Area Telescope on-board of the Fermi gamma-ray Space Telescope has detected the largest amount of gamma-rays to date, in the 20MeV 300GeV energy range, allowing to perform a very sensitive indirect experimental search for DM (by means of high-energy gamma-rays). DM forms large gravitationally bounded structures, the halos, which can host entire galaxies, such as the Milky Way. The DM distribution in the central part of the halos is not experimentally know, despite a very large density enhancement might be present. As secondary gamma rays production is very sensitive to WIMP density, a very effective search can be performed from the regions where the largest density is expected. Therefore the information provided by the DM halo N-body simulations are crucial. The largest gamma-ray signal from DM annihilation is expected from the centre of the Galaxy. In the same region a large gamma-ray background is produced by bright discrete sources and the cosmic-rays interacting with the interstellar gas and the photons fields. Here we report an update of the indirect search for DM from the Galactic Center (GC).

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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