We investigate the possibilities for probing MeV dark matter (DM) particles and primordial black holes (PBHs) (for masses ~ 10¹⁵–10¹⁷ g) at the upcoming radio telescope SKA, using photon signals from the Inverse Compton (IC) effect within a galactic halo. Pair-annihilation or decay of MeV DM particles (into e⁺ e^- pairs) or Hawking radiation from a population of PBHs generates mildly relativistic e which can lead to radio signals through the IC scattering on low energy cosmic microwave background (CMB) photons. We study the ability of SKA to detect such signals coming from nearby ultra-faint dwarf galaxies Segue I and Ursa Major II as well as the globular cluster ω-cen and the Coma cluster. We find that with ~ 100 hours of observation, the SKA improves the Planck constraints on the DM annihilation/decay rate and the PBH abundance for masses in the range ~ 1 to few tens of MeV and above 10¹⁵ to 10¹⁷ g, respectively. Importantly, the SKA limits are independent of the assumed magnetic fields within the galaxies. Previously allowed regions of diffusion parameters of MeV electrons inside a dwarf galaxy that give rise to observable signals at the SKA are also excluded. For objects like dwarf galaxies, predicted SKA constraints depend on both the DM and diffusion parameters. Independent observations in different frequency bands, e.g., radio and γ-ray frequencies, may break this degeneracy and thus enable one to constrain the combined parameter space of DM and diffusion. However, the constraints are independent of diffusion parameters for galaxy clusters such as Coma.

我们研究了在即将到来的射电望远镜SKA上探测MeV暗物质（DM）粒子和原始黑洞（PBH）（质量约为10 ¹⁵ –10 ¹⁷ g）的可能性，并利用来自康普斯逆子（IC）效应的光子信号银河系的光环。一对湮灭或MeV的DM颗粒的衰减（到电子书⁺ ë ^-双）或从PBHs群体霍金辐射产生轻度相对论ë它可以通过低能宇宙微波背景（CMB）光子上的IC散射产生无线电信号。我们研究了SKA探测来自附近超微弱矮星系Segue I和Ursa Major II以及球状星团ω-cen和昏迷星团的信号的能力。我们发现，通过〜100小时的观察，对于质量范围在1〜几十MeV且在10 ¹⁵到10 ¹⁷以上的质量，SKA改善了普朗克对DM hil没/衰减率和PBH丰度的约束。g，分别。重要的是，SKA限制与星系内假定的磁场无关。矮星系内部的MeV电子的扩散参数先前允许的区域（在SKA处产生可观察到的信号）也被排除在外。对于像矮星系这样的物体，预测的SKA约束取决于DM和扩散参数。在不同频带（例如，无线电频率和γ射线频率）中进行独立观察可能会破坏这种退化，从而使人们能够限制DM和扩散的组合参数空间。但是，约束条件与诸如彗星之类的星系团的扩散参数无关。