Dark matter substructure cannot explain properties of the Fermi Galactic Centre excess
Dark matter substructure cannot explain properties of the Fermi Galactic Centre excess
复制标题
暗物质子结构无法解释费米银河中心过剩的特性
DOI：
10.1088/1475-7516/2018/07/060
复制
发表时间：
2016
影响因子：
6.4
通讯作者：
G. Lewis
中科院分区：
文献类型：
--
作者：
H. Clark;P. Scott;R. Trotta;G. Lewis
在银河系的中心已经发现了过量的伽马射线，暗物质的湮灭被认为是一个潜在的来源。这一假设面临着重大的挑战：难以描述天体物理背景，银河系暗物质晕内部的非平凡绝热收缩的需要，以及最近对光子聚集的观察，这表明大多数过剩是由于未解决的点源。在这里，我们指出，发射的明显点状性质完全排除了暗物质对过量的解释。试图用暗物质点源模拟发射，要么是忽略了内斜率的问题，要么是需要一个不切实际的大的朝向银河系中心的微晕分数，要么是在高纬度过度产生观测到的发射。
An excess of gamma rays has been identified at the centre of the Milky Way, and annihilation of dark matter has been posited as a potential source. This hypothesis faces significant challenges: difficulty characterizing astrophysical backgrounds, the need for a non-trivial adiabatic contraction of the inner part of the Milky Way's dark matter halo, and recent observations of photon clustering, which suggest that the majority of the excess is due to unresolved point sources. Here we point out that the apparent point-like nature of the emission rules out the dark matter interpretation of the excess entirely. Attempting to model the emission with dark matter point sources either worsens the problem with the inner slope, requires an unrealistically large minihalo fraction toward the Galactic Centre, or overproduces the observed emission at higher latitudes.