Speaker
Description
We explore the possibility that light Dark Matter (DM) existence is related to first order phase transitions (FOPTs) in the early Universe. In particular, DM particles may be pseudo-Goldstone bosons of spontaneously broken global symmetries beyond the Standard Model. In this case, a new scalar field can interact with the Higgs boson and it can be related to a first order electroweak phase transition. We show the case of Majoron DM from a L or B-L global U(1) spontaneous symmetry breaking, generating a Majorana mass for neutrino.
We will show FOPTs related to Majoron DM can generate a GW stochastic background signal that can be tested in future space-based interferometers such as LISA, TAIJI and Tianqing projects.
We discuss the complementarity of GW physics with colliders and neutrinoless double-beta-decays searches of Majorons.
We also mention the possibility of relating light DM to FOPTs below the electroweak energy scale as a possible explanation of NANOGrav 15yrs anomaly.
