PBH Formation from Overdensities in Delayed Vacuum Transitions 后印本

摘要: Primordial black hole (PBH) formation from first order phase transitions combines two prevalent elements of Beyond the Standard Model physics with wide-ranging consequences. We elaborate on a recently proposed scenario in which inhomogeneities in vacuum energy decay seed the overdensities that collapse to primordial black holes. In this scenario, the PBH mass is determined by the Hubble mass as in conventional formation scenarios, while its number density is determined by the nucleation dynamics of the first-order phase transition. We present a detailed study of the formation probability including some analytical treatments. In addition, we generate populations in the open mass window as well as for the HSC and OGLE candidate microlensing events. This mechanism inevitably creates PBHs in generic first order phase transitions, with significant populations produced in slow and moderately strong phase transitions.