标题： 早期物质主导时期媒介子衰变产生的暗物质 显示英文标题

标题： Dark matter from mediator decay in early matter domination

摘要： 我们研究在早期物质主导时期的场景中，通过媒介子衰变产生的暗物质。 只要媒介子的质量低于宇宙暴胀后的再加热温度，它们就可以在热浴中被动力学访问。 然后，实壳媒介子的衰变可能导致在早期物质主导时期或之前的辐射主导阶段大量产生暗物质。 特别是对于在标准模型下带电的媒介子，由于在远低温度下的逆湮灭，其产生速率可能超过标准的冻结输入通道。 为了获得正确的残留丰度，对高于几TeV的暗物质质量的参数空间有严格的限制。 显示英文摘要

摘要： We study dark matter production from mediator decays in scenarios with an epoch of early matter domination. Particles that mediate interactions between dark matter and the standard model particles are kinematically accessible to the thermal bath as long as their mass is below the reheating temperature of the Universe after inflation. Decay of on-shell mediators can then lead to copious production of dark matter during early matter domination or a preceding radiation-dominated phase. In particular, for mediators that are charged under the standard model, it can exceed the standard freeze-in channel due to inverse annihilations at much lower temperatures (often by many orders of magnitude). The requirement to obtain the correct relic abundance severely constrains the parameter space for dark matter masses above a few TeV.