Gamma-ray bursts at extremely small fluence

TL;DR

This paper discusses a proposed highly sensitive gamma-ray detector capable of discovering numerous neutron star mergers, enabling detailed study of these events and their physical processes even when gravitational wave detectors are offline.

Contribution

It introduces a new gamma-ray detector with significantly higher sensitivity, allowing for the detection of neutron star mergers at small fluences and enhancing multi-messenger astrophysics.

Findings

Potential to discover up to a thousand neutron star mergers annually.

Ability to analyze gamma-ray beam patterns and jet divergence.

Improved understanding of the origin of double relativistic stars.

Abstract

In this review we show that the space experiment with gamma-ray detector with sensitivity 2 orders of magnitude higher than existing ones will make it possible to discover up to a thousand neutron star mergers, even at those moments when gravitational wave (GW) antennas are not working. At the same time, synchronous detection of neutron stars mergers by gamma-ray and GW detectors will make it possible not only to study in detail the physical processes occurring at the time of the catastrophe, but also to determine the full gamma ray beam pattern, including the average jet divergence angle and the real energy of the explosion. A gamma detector that has the required sensitivity at a relatively low flight weight is proposed. The latter, in turn, will make it possible to clarify our ideas about the genesis of double relativistic stars in the Universe.