A bstract In seesaw mechanism, if right handed (RH) neutrino masses are generated
dynamically by a gauged U (1) symmetry breaking, a stochastic gravitational wave …

Ultralight primordial black holes (PBHs)(≲ 10 9 g) completely evaporate via Hawking
radiation (HR) and produce all the particles in a given theory regardless of their other …

We study the possibility of cogenesis of baryon and dark matter (DM) from the out-of-
equilibrium CP violating decay of right handed neutrino (RHN) that are dominantly of non …

Ultra-light primordial black holes with masses M BH< 10 9 g evaporate before big-bang
nucleosynthesis producing all matter fields, including dark matter, in particular super-heavy …

In the classic type I seesaw mechanism with very heavy right-handed (RH) neutrinos, it is
possible to account for dark matter via RH neutrino portal couplings to a feebly interacting …

Inflaton seeds nonthermal leptogenesis by pair-producing right-handed neutrinos in the
seesaw model. We show that the inevitable graviton bremsstrahlung associated with inflaton …

Since the gravitational interaction is universal, any particle that ever existed, if kinematically
accessible, has to be produced through her. We explore the possibility that dark matter is …

We propose a scenario where dark matter (DM) with a wide mass range from a few keV to
PeV can be produced solely from evaporating primordial black holes (PBH), while being …

We study a minimal scenario to realize nonthermal leptogenesis and UV freeze-in of a
Standard Model (SM) gauge singlet fermionic dark matter (DM) simultaneously, with inflaton …

A bstract We consider a minimal type Ib seesaw model where the effective neutrino mass
operator involves two different Higgs doublets, and the two right-handed neutrinos form a …