论文标题
通过M31的无线电观察，对WIMP暗物质歼灭的最新约束
Updated constraints on WIMP dark matter annihilation by radio observations of M31
论文作者
论文摘要
目前的工作得出了利用M31的新无线电观察结果以及对其暗物质分布和其他特性的新研究，对歼灭WIMP参数的强大约束。使用专门针对M31适用的Galprop代码的2D银河模型框架计算了由于DM歼灭而产生的发射特性。这使我们能够完善对该主题的先前研究的各种不准确性。获得了两个代表性歼灭通道的DM约束：$χχ\ rightarrow b \ overline {b} $和$χ\χ\ rightarrowτ^+τ^ - $。在频率范围$ \ $ \ $（0.1--10）GHz中使用了多种无线电数据。结果，对于$ b \ overline {b} $ channel，$ \ $ \ $ \ $ \ $ \ $ \ $ \ $ \ $ \ $ \ $ \ $ \ $ \ $ 40 GEV的结果比$τ^+τ^ - $轻约$ 70 gev- $ \ $ \ $ 40 GEV。相应的质量阈值不确定性范围估计为20--210 GEV和18--89 GEV。所获得的排除率与矮人和AMS-02抗抗脂子测量值的Fermi-Lat观测值具有竞争力。我们的约束不排除M31的伽玛射线外光环和银河系中心过量的解释。用$ M_X \ $ 70 $ GEV的热w imp解释了外晕，将对M31核中的非热无线电通量做出重大贡献，非常适合光谱和形态。最后，我们质疑其他研究中要求的可能性，以通过M31上的无线电数据来稳健地用$ m_x> 100 $ GEV来限制重型热wimp。
The present work derived the robust constraints on annihilating WIMP parameters utilizing new radio observations of M31, as well as new studies of its dark matter distribution and other properties. The characteristics of emission due to DM annihilation were computed in the frame of 2D galactic model employing GALPROP code adapted specifically for M31. This enabled us to refine various inaccuracies of previous studies on the subject. DM constraints were obtained for two representative annihilation channels: $χχ\rightarrow b\overline{b}$ and $χχ\rightarrow τ^+τ^-$. A wide variety of radio data was utilized in the frequency range $\approx$(0.1--10) GHz. As the result the thermal WIMP lighter than fiducially $\approx$ 70 GeV for $b\overline{b}$ channel and $\approx$ 40 GeV for $τ^+τ^-$ was excluded. The corresponding mass threshold uncertainty ranges were estimated to be 20--210 GeV and 18--89 GeV. The obtained exclusions are competitive to those from Fermi-LAT observations of dwarfs and AMS-02 measurements of antiprotons. Our constraints do not exclude the explanation of the gamma-ray outer halo of M31 and the Galactic center excess by annihilating DM. The thermal WIMP with $m_x \approx 70$ GeV, which explains the outer halo, would make a significant contribution to the non-thermal radio flux in M31 nucleus, fitting well both the spectrum and morphology. And, finally, we questioned the possibility claimed in other studies to robustly constrain heavy thermal WIMP with $m_x > 100$ GeV by radio data on M31.
