Quantum and thermal corrections to dark matter annihilation

随着暗物质观测和探测能力变得更加精确和多样化，基于树级湮灭的理论计算往往不再足够。拟议的项目侧重于暗物质过程和模型，其中循环效应很重要。在缺乏确定的暗物质非引力证据的情况下，目标不是精确的物理，而是量子效应，它是巨大的，导致暗物质湮灭的一阶或定性修改。它们通过索默菲尔德效应影响了早期宇宙中大量暗物质粒子的冻结，以及今天的暗物质湮灭。在这里，索默菲尔德效应、大电弱对数以及电弱规色子辐射可能导致宇宙射线中可探测到的光子、中微子和带电粒子光谱的改变。该项目通过对撞机物理学中更熟悉的方法（有效场论、重整化群进化、恢复技术）来解决这些循环效应，并将它们与暗物质现象学相结合。它主要关注质量大于电弱尺度的重弱相互作用暗物质粒子（wimp），其中上述效应很大。此外，还研究了热等离子体对冻结过程的影响。对于一般的暗物质湮灭，这些研究具有纯粹的理论意义，并阐明了红外有限性的基本问题。然而，当湮灭过程的某些部分对与等离子体温度相称的尺度敏感时，就不再是这种情况了，就像索默菲尔德效应一样。

As dark matter observation and detection capabilities become more precise and more diverse, theoretical calculations based on tree-level annihilation are often no longer sufficient. The proposed project focuses on dark matter processes and models where loop effects are important. In the absence of definitive non-gravitational evidence of dark matter, the goal is not so much on precision physics, but on quantum effects, which are large and result in order one or qualitative modifications of dark matter annihilation. These affect the freeze-out of the relic abundance of dark matter particles in the early Universe through the Sommerfeld effect, as well as dark matter annihilation today. Here the Sommerfeld effect and large electroweak logarithms as well as electroweak gauge-boson radiation may result in modifications of photon, neutrino and charged-particle spectra detectable in cosmic rays. The project addresses these loop effects through methods more familiar from collider physics (effective field theory, renormalization-group evolution, resummation techniques) and combines them with dark matter phenomenology. It focuses mainly on heavy weakly interacting dark matter particles (WIMPs) with mass larger than the electroweak scale, where the above effects are large. In addition, the influence of the hot thermal plasma on the freeze-out process will be investigated. For generic dark matter annihilation these investigations are of purely theoretical interest and clarify fundamental questions of infrared finiteness. However, this is no longer the case when parts of the annihilation process are sensitive to scales commensurate with the temperature of the plasma, as is the case for the Sommerfeld effect.