We study the impact of thermalization and number-changing processes in the dark sector on the yield of gravitationally produced dark matter (DM). We take into account the DM production through the s-channel exchange of a massless graviton both from the scattering of inflatons during the reheating era, and from the Standard Model bath via the UV freeze-in mechanism. By considering the DM to be a scalar, a fermion, and a vector boson we show, in a model-independent way, that DM self-interaction gives rise to a larger viable parameter space by allowing lower reheating temperature to be compatible with Planck observed relic abundance. As an example, we also discuss our findings in the context of the ℤ₂-symmetric scalar singlet DMmodel.

我们研究了暗区中的热化和数量变化过程对引力产生的暗物质 (DM) 产量的影响。我们考虑了通过无质量引力子的s通道交换产生的 DM 产生，这既来自再加热时代的暴胀子散射，也来自标准模型浴通过 UV 冻结机制。通过将 DM 视为标量、费米子和矢量玻色子，我们以独立于模型的方式展示了 DM 自相互作用通过允许较低的再加热温度与普朗克观察到的兼容而产生更大的可行参数空间遗迹丰富。作为一个例子，我们还在 ℤ _{2 -}对称标量单线态 DM 模型的背景下讨论我们的发现。