Speaker
Sonali VERMA
(ULB, Brussels)
Description
In this talk, I will show how measurements of the intergalactic medium (IGM) temperature from the Lyman-α forest can be used to constrain long-lived dark sector particles. Such particles deposit energy into the IGM through decays to Standard Model states, thereby modifying the thermal history of the Universe. I will also revisit constraints on these models from Planck CMB measurements of the optical depth to reionization, and demonstrate that Lyman-α bounds provide a complementary probe to those from the CMB. The resulting model-independent constraints can be reinterpreted across a wide range of decaying dark sector scenarios, such as evaporating primordial black holes and dark photons.
Authors
Laura Lopez-Honorez
(ULB, Brussels)
Sonali VERMA
(ULB, Brussels)