研究聚焦于温暗物质（WDM），特别是3 keV附近的质量区域，该区域的密度扰动受到抑制，导致低质量星系形成延迟，进而使再离子化过程向晚期转移。通过分析星系光度函数、再电离历史和Gunn-Petersson效应，即使调整模拟中的恒星形成效率以匹配观测到的紫外星系光度函数，WDM模型的Gunn-Peterson光学深度仍保留了再离子化延迟的显著特征。然而，由于现代星系形成模拟中恒星形成和恒星反馈模型的不确定性，基于再离子化观测得出的暗物质性质结论仍然依赖于模型设定。
摘要：
In models with dark matter made of particles with keV masses, such as a sterile neutrino, small-scale density perturbations are suppressed, delaying the period at which the lowest mass galaxies are formed and therefore shifting the reionization processes to later epochs. In this study, focusing on Warm Dark Matter (WDM) with masses close to its present lower bound, i.e. around the $3$ keV region, we derive constraints from galaxy luminosy functions, the ionization history and the Gunn-Peterson effect. We show that even if star formation efficiency in the simulations is adjusted to match the observed UV galaxy luminosity functions in both CDM and WDM models, the full distribution of Gunn-Peterson optical depth retains the strong signature of delayed reionization in the WDM model. However, until the star formation and stellar feedback model used in modern galaxy formation simulations is constrained better, any conclusions on the nature of dark matter derived from reionization observables remain model-dependent.
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