论文标题
结构形成限制轴突状暗物质
Structure Formation Limits on Axion-Like Dark Matter
论文作者
论文摘要
我们得出了由kev尺度轴测颗粒（ALP）组成的暗物质（DM）的结构形成限制，该粒子（ALP）通过与光子和标准模型（SM）费米子的相互作用而产生的。我们采用Lyman-Alpha（Ly-α）森林数据集以及观察到的银河系（MW）Subhalos数量。我们比较了使用Maxwell-Boltzmann和量子统计来描述SM浴的结果。应该强调的是，对数差异的存在使生产率的计算变得复杂，这无法通过简单的功率定律行为进行参数化。获得的结果，结合X射线边界，排除了质量低于$ \ sim 19 \，\ Mathrm {kev} $的光pophilic“冷冻” ALP DM的可能性。对于主要与Sm fermions的DM夫妇的辐照ALP场景，ALP DM分布函数在较低的动量下达到峰值，因此，对于这种实现，我们发现DM质量的限制较弱。未来的设施，例如即将到来的Vera C. Rubin天文台，将提供可将当前界限可显着提高到$ \ sim 80 \，\ mathrm {kev} $的测量值。
We derive structure formation limits on dark matter (DM) composed of keV-scale axion-like particles (ALPs), produced via freeze-in through the interactions with photons and Standard Model (SM) fermions. We employ Lyman-alpha (Ly-α) forest data sets as well as the observed number of Milky Way (MW) subhalos. We compare results obtained using Maxwell-Boltzmann and quantum statistics for describing the SM bath. It should be emphasized that the presence of logarithmic divergences complicates the calculation of the production rate, which can not be parameterized with a simple power law behaviour. The obtained results, in combination with X-ray bounds, exclude the possibility for a photophilic "frozen-in" ALP DM with mass below $\sim 19\,\mathrm{keV}$. For the photophobic ALP scenario, in which DM couples primarily to SM fermions, the ALP DM distribution function is peaked at somewhat lower momentum and hence for such realization we find weaker limits on DM mass. Future facilities, such as the upcoming Vera C. Rubin observatory, will provide measurements with which the current bounds can be significantly improved to $\sim 80\,\mathrm{keV}$.
