Hints of dark matter-neutrino interactions in Lyman-$\hat{I}\pm$ data

Abstract

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 CMB, BAO and, in particular, Lyman-$\hat{I}\pm$ data. We find that the latter hint to a significant departure from $\hat{I}›$CDM, with a preference for an interaction strength about 3$\ddot{I}ƒ$ away from zero. We trace the origin of this preference back to the additional tilt that the interacting scenario can imprint on the Lyman-$\hat{I}\pm$ flux power spectrum, solving a well-known tension in the determination of this quantity between early-time and Lyman-$\hat{I}\pm$ probes. Future work including complementary Lyman-$\hat{I}\pm$ data as well as dedicated numerical simulations will be crucial in order to test these results.

7+4 pages with 5 figures and 2 tables. Published version