New constraints on sterile neutrino dark matter from NuSTAR M31 observations
New constraints on sterile neutrino dark matter from NuSTAR M31 observations
复制标题
DOI：
10.1103/physrevd.99.083005
复制
发表时间：
2019-01
影响因子：
5
通讯作者：
K. Ng;B. Roach;K. Perez;J. Beacom;S. Horiuchi;R. Krivonos;D. Wik
中科院分区：
文献类型：
--
作者：
K. Ng;B. Roach;K. Perez;J. Beacom;S. Horiuchi;R. Krivonos;D. Wik
我们使用对M31的联合1.2ms的$NuSTAR$观测来搜索来自无菌中微子暗物质衰变的X射线线。在$NuSTAR$分析中，我们第一次始终如一地考虑了聚焦视野和非聚焦视野的信号贡献。我们还通过对每个观测单独执行频谱拟合并以统计方式合并结果来减少建模系统的不确定性，而不是堆叠频谱。我们没有发现未知线的证据，因此得出了不孕中微子参数的极限。我们的结果对暗物质质量施加了严格的限制，这使得中微子混合产生的稀薄中微子暗物质的可用参数空间减少了大约三分之一。额外的$NuSTAR$观测，加上改进的低能量背景建模，可能会在未来探测到剩余的参数空间。最后，我们还报道了一般暗物质衰减率和湮灭截面与模型无关的极限。
We use a combined 1.2 Ms of $NuSTAR$ observations of M31 to search for X-ray lines from sterile neutrino dark matter decay. For the first time in a $NuSTAR$ analysis, we consistently take into account the signal contribution from both the focused and unfocused fields of view. We also reduce the modeling systematic uncertainty by performing spectral fits to each observation individually and statistically combining the results, instead of stacking the spectra. We find no evidence of unknown lines, and thus derive limits on the sterile neutrino parameters. Our results place stringent constraints for dark matter masses $\gtrsim 12$ keV, which reduces the available parameter space for sterile neutrino dark matter produced via neutrino mixing ($e.g.$, in the $\nu$MSM) by approximately one-third. Additional $NuSTAR$ observations, together with improved low-energy background modeling, could probe the remaining parameter space in the future. Lastly, we also report model-independent limits on generic dark matter decay rates and annihilation cross sections.