论文标题
搜索暗物质信号,以选择与H.E.S.S的银河系中最近发现的DES DEDWARF GARAXY卫星
Search for dark matter signals towards a selection of recently-detected DES dwarf galaxy satellites of the Milky Way with H.E.S.S
论文作者
论文摘要
银河系的矮球星系卫星是与伽玛射线间接检测暗物质的主要目标,这是由于其邻近性,高暗物质含量和缺乏非热发射过程。最近,黑暗能源调查(DES)揭示了南部半球天空中新的超生物矮人球形星系的存在,因此,理想的位置可用于基于地面的观测,并具有成像大气Cherenkov望远镜阵列H.E.S.S.S.我们提出了使用H.E.S.S.最近对网状II,图卡纳II,图卡纳III,图卡纳IV和Grus II卫星进行了观测。从对任何单个对象的观察值或对所有数据集的组合分析中的观察值中都没有发现明显的高能量伽马射线过量。使用矮星晕中暗物质分布的最新建模,我们首次对DES卫星个体进行了计算,并在弱相互作用的大型粒子的形式中对Cherenkov望远镜观察的结合约束。组合95%C.L. observed upper limits reach $\langle σv \rangle \simeq 1 \times 10^{-23}$ cm$^3$s$^{-1}$ in the $W^+W^-$ channel and $4 \times 10^{-26}$ cm$^3$s$^{-1}$ in the $γγ$ channels for a dark matter mass of 1.5 TeV. H.E.S.S.约束很好地补充了Fermi-Lat,HAWC,Magic和Veritas的结果,目前是多GEV/Multi-TEV质量范围中$γγ$通道中最严格的结果。
Dwarf spheroidal galaxy satellites of the Milky Way are prime targets for indirect detection of dark matter with gamma rays due to their proximity, high dark matter content and absence of non-thermal emission processes. Recently, the Dark Energy Survey (DES) revealed the existence of new ultra-faint dwarf spheroidal galaxies in the southern-hemisphere sky, therefore ideally located for ground-based observations with the imaging atmospheric Cherenkov telescope array H.E.S.S. We present a search for very-high-energy ($E\gtrsim100$ GeV) gamma-ray emission using H.E.S.S. observations carried out recently towards Reticulum II, Tucana II, Tucana III, Tucana IV and Grus II satellites. No significant very-high-energy gamma-ray excess is found from the observations on any individual object nor in the combined analysis of all the datasets. Using the most recent modeling of the dark matter distribution in the dwarf galaxy halo, we compute for the first time on DES satellites individual and combined constraints from Cherenkov telescope observations on the annihilation cross section of dark matter particles in the form of Weakly Interacting Massive Particles. The combined 95% C.L. observed upper limits reach $\langle σv \rangle \simeq 1 \times 10^{-23}$ cm$^3$s$^{-1}$ in the $W^+W^-$ channel and $4 \times 10^{-26}$ cm$^3$s$^{-1}$ in the $γγ$ channels for a dark matter mass of 1.5 TeV. The H.E.S.S. constraints well complement the results from Fermi-LAT, HAWC, MAGIC and VERITAS and are currently the most stringent in the $γγ$ channels in the multi-GeV/multi-TeV mass range.