Multimessenger constraints on dark matter annihilation into electron–positron pairs
Multimessenger constraints on dark matter annihilation into electron–positron pairs
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DOI：
10.1093/mnras/stt2488
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发表时间：
2012-12
影响因子：
4.8
通讯作者：
M. Wechakama;Y. Ascasibar
中科院分区：
文献类型：
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作者：
M. Wechakama;Y. Ascasibar
我们在暗物质湮灭的背景下研究了银河系中电子和正电子的产生。相关截面的上限是通过将不同波长的观测数据（来自Haslam， WMAP和Fermi全天强度图）与PAMELA， Fermi和HESS最近对太阳附近电子和正电子光谱的测量相结合而获得的。我们考虑了无线电和微波波段的同步辐射，以及逆康普顿散射和伽玛射线能量的终态辐射。根据我们的结果，如果候选暗物质的质量小于几个GeV，则暗物质湮灭成电子-正电子对的横截面不应高于热遗迹的规范值。此外，我们还推导了银河系暗物质晕密度剖面的内对数斜率alpha的严格上限（如果m_dm < 5 GeV, alpha < 1；如果m_dm < 100 GeV, alpha < 1.3；如果m_dm < 2 TeV, alpha < 1.5），假设截面= 3 × 10^(-26) cm^3 s（-1）。一个比alpha陡约1.5的对数斜率很难与一个比1tev轻的热遗迹兼容，不管主导湮灭通道是什么。
We investigate the production of electrons and positrons in the Milky Way within the context of dark matter annihilation. Upper limits on the relevant cross-section are obtained by combining observational data at different wavelengths (from Haslam, WMAP, and Fermi all-sky intensity maps) with recent measurements of the electron and positron spectra in the solar neighbourhood by PAMELA, Fermi, and HESS. We consider synchrotron emission in the radio and microwave bands, as well as inverse Compton scattering and final-state radiation at gamma-ray energies. According to our results, the dark matter annihilation cross-section into electron-positron pairs should not be higher than the canonical value for a thermal relic if the mass of the dark matter candidate is smaller than a few GeV. In addition, we also derive a stringent upper limit on the inner logarithmic slope, alpha, of the density profile of the Milky Way dark matter halo (alpha < 1 if m_dm < 5 GeV, alpha < 1.3 if m_dm < 100 GeV and alpha < 1.5 if m_dm < 2 TeV) assuming that cross-section = 3 x 10^(-26) cm^3 s(-1). A logarithmic slope steeper than alpha about 1.5 is hardly compatible with a thermal relic lighter than about 1 TeV, regardless of the dominant annihilation channel.