21st Patras Workshop on Axions, WIMPs and WISPs

Primordial Black Hole Dark Matter from Non-Topological Solitons

Not scheduled

20m

University of Western Australia

Oral Presentation

Speaker

Shunsuke Neda (Institute for Cosmic Ray Research, The University of Tokyo)

Description

Non-topological solitons arising in theories beyond the Standard Model can generate sizable Poisson density fluctuations in the early Universe. If the solitons temporarily dominate the energy density, these fluctuations grow during the resulting early matter-dominated era and can collapse into primordial black holes (PBHs), providing a possible origin of dark matter. Previous studies of this scenario assumed a monochromatic soliton mass distribution and did not fully address PBH formation from perturbations generated inside the horizon. We develop a general framework for evaluating density perturbations arising from an arbitrary soliton mass distribution and clarify the collapse condition for sub-horizon perturbations during an early matter-dominated era. Applying the formalism to gauge-mediated Q-balls with a charge distribution obtained from lattice simulations, we show that the resulting PBHs can constitute all of the dark matter.