AI 中文总结
该研究提出跷跷板宇宙学，探讨暴胀子通过RHNs传递能量的微扰再加热过程，分析其热演化规律及对暗物质产生的影响，关联中微子质量、原初热历史与暗物质等现象。
AI 中文摘要
我们研究微扰再加热过程，其中暴胀子通过I型跷跷板机制中负责轻中微子质量的右手轻子（RHNs）将能量传递给标准模型，我们将由此产生的非标准热历史称为跷跷板宇宙学。当RHNs以相对论性产生且寿命足够长时，会形成暴胀子、相对论性RHNs、非相对论性RHNs以及标准模型辐射主导的特征序列。我们求解玻尔兹曼方程组，同时保留非热RHNs分布的产生时间依赖性及其相对论性到非相对论性的转变。在暴胀子主导期间，标准模型温度迅速趋近于一个平台，随后在相对论性RHNs主导期间按$a^{-1/4}$缩放，在非相对论性RHNs主导期间按$a^{-3/8}$缩放。我们研究跷跷板宇宙学对暗物质产生的影响：通过暴胀子衰变的直接产生相较于常规再加热可增强约$m_\theta/(2m_N)$倍，而紫外区的冻结产生呈现出临界温度幂次$p=12$和$20$，在最终辐射主导时代前可能产生较大贡献。因此，跷跷板宇宙学将中微子质量产生、原初核合成（BBN）前的热历史以及暗物质产生、重子生成等现象联系起来。
英文摘要
We study perturbative reheating in which the inflaton transfers its energy to the Standard Model through right-handed neutrinos (RHNs) responsible for light-neutrino masses via the type-I seesaw mechanism. We refer to the resulting nonstandard thermal history as $seesaw$ $cosmology$. When produced relativistically and sufficiently long lived, the RHNs generate a characteristic sequence of inflaton, relativistic-RHN, nonrelativistic-RHN, and Standard Model radiation domination. We solve the Boltzmann system while retaining the production-time dependence of the nonthermal RHN distribution and its relativistic-to-nonrelativistic transition. The Standard Model temperature rapidly approaches a plateau during inflaton domination and subsequently scales as $a^{-1/4}$ and $a^{-3/8}$ during relativistic- and nonrelativistic-RHN domination, respectively. We investigate the implications of seesaw cosmology for dark-matter production. Direct production through inflaton decays can be enhanced relative to conventional reheating by a factor of order $m_ϕ/(2m_N)$, while ultraviolet freeze-in exhibits the critical temperature powers $p = 12$ and $20$, leading to potentially large contributions before the final radiation-dominated era. Seesaw cosmology therefore connects neutrino-mass generation, the pre-BBN thermal history and phenomena such as dark-matter production and baryogenesis.
Comments16+4 pages, 3 figures
