SciPost Physics (Mar 2023)

Hot and heavy dark matter from a weak scale phase transition

  • Iason Baldes, Yann Gouttenoire, Filippo Sala

DOI
https://doi.org/10.21468/scipostphys.14.3.033
Journal volume & issue
Vol. 14, no. 3
p. 033

Abstract

Read online

We point out that dark matter which is produced non-adiabatically in a phase transition (PT) with fast bubble walls receives a boost in velocity which leads to long free-streaming lengths. We find that this could be observed via the suppressed matter power spectrum for dark matter masses around $\mathbf{ 10^8 - 10^9}$ GeV and energy scales of the PT around $\mathbf{ 10^{2} - 10^3}$ GeV. The PT should take place at the border of the supercooled regime, i.e. approximately when the Universe becomes vacuum dominated. This work offers novel physics goals for galaxy surveys, Lyman-$\alpha$, stellar stream, lensing, and 21-cm observations, and connects these to the gravitational waves from such phase transitions, and more speculatively to possible telescope signals of heavy dark matter decay.