Hints of dark matter-neutrino interactions in Lyman-? data

In this work we investigate the possibility that dark matter and (massive) neutrinos can interact via a simple, constant cross section. Building on previous numerical efforts, we constrain this model with Cosmic Microwave Background, Baryon Acoustic Oscillations, and, in particular, Lyman-?? data. We find that the latter hint to a significant departure from ACDM, with a preference for an interaction strength about 3?? away from zero. We trace the origin of this preference back to the additional tilt that the interacting scenario can imprint on the Lyman-?? flux power spectrum, solving a well-known tension in the determination of this quantity between early-time and Lyman-?? probes. Future work including complementary Lyman-?? data as well as dedicated numerical simulations will be crucial in order to test these results.