Related papers: Rescuing High-Scale Leptogenesis using Primordial …
Leptogenesis induced by the oscillations of GeV-scale neutrinos provides a minimal and testable explanation of the baryon asymmetry of the Universe. In this work we extend previous studies invoking only two heavy neutrinos to the case of…
Instead of creating the observed baryon asymmetry of the universe by the decay of right-handed (RH) neutrinos to left-handed leptons, we propose to generate it dominantly by the decay of the RH neutrinos to RH leptons. This mechanism turns…
We explore the possibility of embedding thermal leptogenesis within a first-order phase transition (FOPT) such that RHNs remain massless until a FOPT arises. Their sudden and violent mass gain allows the neutrinos to become thermally…
If primordial black holes (PBHs) contribute more than 10 percent of the dark matter (DM) density, their energy density today is of the same order as that of the baryons. Such a cosmic coincidence might hint at a mutual origin for the…
We present a novel realization of leptogenesis from the decays of sterile (right-handed) neutrinos (RHNs) produced from runaway bubble collisions at a first order phase transition. Such configurations can produce heavy RHNs with mass many…
Although the dark matter is usually assumed to be some form of elementary particle, primordial black holes (PBHs) could also provide some of it. However, various constraints restrict the possible mass windows to $10^{16}$ - $10^{17}\,$g,…
Theories of large extra dimensions (LEDs) such as the Arkani-Hamed, Dimopoulos & Dvali scenario predict a "true" Planck scale $M_\star$ near the TeV scale, while the observed $M_{pl}$ is due to the geometric effect of compact extra…
With entropy injection, an early matter-dominated epoch (EMD) impels the axion decay constant $f_a$ towards larger values to produce correct axion dark matter (DM) abundance, thereby unfolding the low-mass axion ($m_a\lesssim 10^{-5}$ eV)…
Primordial Black Hole Remnants(PBHRs) can be considered as a primary source of cold dark matter. Hybrid inflation provides a possible framework for production of primordial black holes(PBHs) and these PBHs evaporate subsequently to produce…
Measuring a non-zero value for the cross section of any lepton number violating (LNV) process would put a strong lower limit on the washout factor for the effective lepton number density in the early universe at times close to the…
Primordial Black Holes (PBHs) are capable of emitting extremely energetic particles independent of their interactions with the Standard Model. In this work, we investigate whether PBHs evaporating in the early universe could be responsible…
Primordial black holes (PBHs) formed from the collapse of density fluctuations provide a unique window into the physics of the early Universe. Their evaporation through Hawking radiation around the epoch of Big Bang nucleosynthesis (BBN)…
We update the constraints on the fraction of the Universe that may have gone into primordial black holes (PBHs) over the mass range $10^{-5}\text{--}10^{50}$ g. Those smaller than $\sim 10^{15}$ g would have evaporated by now due to Hawking…
Primordial black holes (PBHs) hypothetically generated in the first instants of life of the Universe are potential dark matter (DM) candidates. Focusing on PBHs masses in the range $[5 \times10^{14} - 5 \times 10^{15}]$g, we point out that…
Primordial black holes (PBH), while still constituting a viable dark matter component, are expected to evaporate through Hawking radiation. Assuming the semi-classical approximation holds up to near the Planck scale, PBHs are expected to…
We propose a novel realisation of leptogenesis that relies on the out-of-equilibrium decay of an axion-like particle (ALP) into right-handed Majorana neutrinos (RHNs) in the early Universe. With respect to standard thermal leptogenesis, our…
We propose a minimal and motivated extension of the Standard Model characterised by an approximate lepton number conservation, which is able to simultaneously generate neutrino masses and to account for a successful baryogenesis via…
Primordial black holes (PBHs) are able to produce light dark matter (DM) particles via Hawking radiation, and yield a flux of boosted DM that can be probed at underground DM direct detection experiments. We analyze both galactic and…
The primordial black holes (PBHs) play as a novel source to radiate light elementary particles of energies in the region of a few hundred MeV. We explore the possibility that the axion-like particles (ALPs) with mass less than 1 MeV are…
Sufficiently light primordial black holes (PBH) could evaporate in the very early universe and dilute the preexisting baryon asymmetry and/or the frozen density of stable relics. The effect is especially strong in the case that PBHs decayed…