Constraints on the Number Density of Evaporating Primordial Black Holes for the Chromospheric Evaporation Models

TL;DR

This paper sets limits on the local density of evaporating primordial black holes based on gamma-ray burst data, testing chromospheric evaporation models through analysis of cosmic-ray detector fluctuations.

Contribution

It provides new constraints on primordial black hole density using gamma-ray observations and fluctuation analysis, specifically within chromospheric evaporation frameworks.

Findings

No significant gamma-ray burst detections beyond background expectations

A 7.9 sigma fluctuation event observed

Constraints established on primordial black hole density in the Galaxy

Abstract

Cosmic gamma-ray bursts with primary-photon energies > 10 GeV are sought in the data from the Andyrchy array obtained in the mode of detection of a single cosmic-ray component during a net observation period of 2005.4 d. The distribution of fluctuations of the detector counting rate agrees with the expected cosmic-ray background, the only exception being an event with a deviation of 7.9 sigma. Constraints on the number density of evaporating primordial black holes in a local region of the Galaxy are obtained for the chromospheric evaporation models.