Speaker
Piotr Toczek
(Uniwersytet Warszawski)
Description
Slow first-order phase transitions generate large inhomogeneities that can lead to the formation of primordial black holes (PBHs). We show that the gravitational wave (GW) spectrum then consists of a primary component sourced by bubble collisions and a secondary one induced by large perturbations. The latter gives the dominant peak if $\beta/H_0 <12$, impacting, in particular, the interpretation of the recent PTA data. The GW signal associated with a particular PBH population is stronger than in typical scenarios because of a negative non-Gaussianity of the perturbations and it has a distinguishable shape with two peaks.
Primary authors
Dr
Marek Lewicki
(Uniwersytet Warszawski)
Piotr Toczek
(Uniwersytet Warszawski)
Dr
Ville Vaskonen
(NICPB, Tallin)