New Horizons in Primordial Black Hole physics (NEHOP)

Session

Session 12

Jun 21, 2023, 4:40 PM

Naples, Italy

Conveners

Session 12

• Chair: Jessica Turner

1. Primordial Extremal Black Holes

Yang Bai (University of Wisconsin-Madison)

6/21/23, 4:40 PM

Talk

We show that primordial near-extremal charged black holes with a wide range of masses from the Planck scale to around 10^9 grams could be cosmologically stable and provide a viable explanation for dark matter. The near-extremal charged black holes can carry either the Standard Model magnetic charges or other dark gauge charges. Several observational methods including the merger events of...

49. Axion-like particles from light primordial black holes

Mr Daniele Montanino (Università del Salento & INFN)

6/21/23, 5:00 PM

Talk

We consider a cosmological scenario in which the very early Universe experienced a transient epoch of matter domination due to the formation of a large population of primordial black holes (PBHs) with masses $M \leq 10^9~{\rm g}$, that evaporate before Big Bang nucleosynthesis. In this context, Hawking radiation would be a non-thermal mechanism to produce a cosmic background of axion-like...

66. Cosmological Magnetic Fields from Primordial Kerr-Newman Black Holes

Gordan Krnjaic (Fermilab & University of Chicago)

6/21/23, 5:20 PM

Talk

The origin of our universe's cosmological magnetic fields remains a mystery. In this study, we consider whether these magnetic fields could have been generated in the early universe by a population of charged, spinning primordial black holes. To this end, we calculate the strength and correlation length of the magnetic fields generated by this population, and describe their evolution up to the...

42. Hot spots around small primordial black holes

Kyohei Mukaida (KEK)

6/21/23, 5:40 PM

Talk

Small PBHs with masses $≲ 10^9\,g$ completely evaporate before the big bang nucleosynthesis (BBN). One of the important traces of such small PBHs is that the Hawking radiation emitted from these PBHs heats up the ambient plasma if its temperature is lower than the Hawking temperature. In this talk, we discuss the formation of a locally high-temperature region around a small PBH and see how it...

59. Limits on light primordial black holes from high-scale leptogenesis

Jacob Gunn (University of Naples Federico II)

6/21/23, 6:00 PM

Highlight talk

Among mechanisms for generating the baryon asymmetry of the universe, leptogenesis is attractive since it simultaneously explains the small neutrino masses via the seesaw mechanism. Experiments offer some valuable constraints, but the parameter space of even minimal leptogenesis models are high-dimensional and difficult to probe directly. However considering a simple and well studied...