Experimental search of bursts of very high energy gamma rays from primordial black holes

TL;DR

This paper reports on a search for high-energy gamma-ray bursts from primordial black holes using the Andyrchy air-shower array, setting new upper limits on their local concentration in the galaxy.

Contribution

It introduces a new experimental upper limit on primordial black hole evaporation events based on air-shower data and a multidimensional analysis method to reduce cosmic ray background.

Findings

New upper limit on primordial black hole concentration in the galaxy

Application of multidimensional analysis to distinguish gamma-ray bursts

Comparison of results with other experiments

Abstract

The technical procedure of a search of bursts of very high energy gamma rays from evaporation of primordial black holes on air-shower array "Andyrchy" of Baksan Neutrino Observatory of Institute for Nuclear Research is described. The theoretical model used in the present work assumes that the chromosphere around the evaporating black hole does not form. For minimization of the cosmic ray background the method of multidimensional analysis of modelled as well as experimentally detected events is applied. The new upper limit on the concentration of evaporating primordial black holes in the local region of Galaxy is obtained. The comparison of the results of different experiments is given.