论文标题
早期宇宙中能量颗粒的多物种热化级联
Multi-Species Thermalization Cascade of Energetic Particles in the Early Universe
论文作者
论文摘要
BSM物理学中的重型颗粒很丰富，在一般情况下，将占主导地位的宇宙能量密度。由此产生的事物主导的ERA必须在大爆炸核合成开始之前通过质量$ m $的重物成分的衰减到温度$ t $的热浴中。热化的过程主要涉及能量颗粒的近乎共线分布成两个能量较低的颗粒。这些过程的正确处理需要包含抑制分裂率的连贯效应。我们写下并在数值上求解所得的耦合玻尔兹曼方程，包括标准模型（SM）的所有仪表玻色子和费米子。然后，我们评论非热光谱对比率$ m/t $的依赖性，以及物质衰减率和分支比对各种SM颗粒的依赖性。
Heavy long-lived particles are abundant in BSM physics and will, under generic circumstances, get to dominate the energy density of the universe. The resulting matter dominated era has to end before the onset of Big Bang Nucleosynthesis through the decay of the heavy matter component of mass $M$ into a thermal bath of temperature $T$. The process of thermalization primarily involves near-collinear splittings of energetic particles into two particles with lower energy. The correct treatment of these processes requires the inclusion of coherence effects which suppress the splitting rate. We write down and numerically solve the resulting coupled Boltzmann equations including all gauge bosons and fermions of the Standard Model (SM). We then comment on the dependence of the nonthermal spectra on the ratio $M/T$, as well as on the matter decay rate and branching ratios into various SM particles.
