论文标题
研究银河系矮球星系扩展对使用费米 - 拉特数据的暗物质搜索的影响
Investigating the effect of Milky Way dwarf spheroidal galaxies extension on dark matter searches with Fermi-LAT data
论文作者
论文摘要
银河系的卫星星系具有较高的质量到光比和少量巴属含量的卫星星系，即矮球星系（DSPHS），是通过其最终歼灭产物中的最终歼灭产物进入高含量的光子的最有希望的目标之一。以前，使用Fermi大面积望远镜（LAT）的数据，使用DSPHS的DM发射类似点样的DM发射来对DM候选者进行强大限制。但是，由于其高的DM密度和接近性，DSPHS实际上具有足够的角伸展，可以由费米 - 拉特检测到。在这里，我们首次评估了对角度扩展的影响在搜索伽马射线DM信号对具有Fermi-LAT的已知DSPHS时的影响。我们表明，根据所考虑的DSPH，DM横截面上的限制可以削弱2-2.5倍，而对堆叠的影响，即合并的影响，最多是1.5-1.8，这取决于歼灭通道。当将DSPHS限制与其他多理解剂DM约束并测试异常“过量”的DM解释时，此结果是相关的。
Satellite galaxies of the Milky Way with high mass-to-light ratios and little baryon content, i.e. dwarf spheroidal galaxies (dSphs), are among the most promising targets to detect or constrain the nature of dark matter (DM) through its final annihilation products into high-energy photons. Previously, the assumption that DM emission from dSphs is point-like has been used to set strong constraints on DM candidates using data from the Fermi Large Area Telescope (LAT). However, due to their high DM densities and proximity, dSphs actually have sufficient angular extension to be detected by the Fermi-LAT. Here, we assess, for the first time, the impact of accounting for angular extension in the search for gamma-ray DM signals towards known dSphs with Fermi-LAT. We show that, depending on the dSph under consideration, limits on the DM cross section can be weakened by up to a factor of 2-2.5, while the impact on the stacked, i.e. combined, limits is at most 1.5-1.8 depending on the annihilation channel. This result is of relevance when comparing dSphs limits to other multi-messenger DM constraints and for testing the DM interpretation of anomalous "excesses".
