Speaker
Description
The Lyman-alpha forest is a powerful cosmological probe of matter density fluctuations in the weakly non-linear regime through the high redshift and underdense intergalactic medium (IGM). The most commonly used statistic to characterize these fluctuations is the 1D flux power spectrum. On small scales, the Lyman-alpha forest traces the properties of dark matter, encoding information on its still unknown nature. At the same time, the flux power spectrum is sensitive to complex gas dynamics arising from IGM photoheating during reionization. As such, the Lyman-alpha forest provides constraints that are complementary to other probes, such as the CMB. In this talk, I will present recent constraints on Cold+Warm Dark Matter (CWDM), in which structure growth is affected by the free-streaming of the warm component, using the Sherwood-Relics simulation suite and high signal-to-noise ratio, high-redshift spectra from UVES and HIRES spectrographs. These results highlight how small-scale features in the forest reveal fundamental aspects of both dark matter and the IGM thermal history.