A proposed network of Gamma-ray Burst detectors on the Global Navigation Satellite System Galileo G2

TL;DR

This paper proposes equipping Galileo G2 satellites with gamma-ray burst detectors to improve localization accuracy, enabling better study of GRBs and kilonovae despite large error regions from gravitational wave detectors.

Contribution

It introduces a novel satellite network concept using Galileo G2 satellites for gamma-ray burst detection and localization, leveraging their orbital position for enhanced triangulation.

Findings

Simulations show localization of faint short GRBs to 1 degree radius.

The proposed network reduces costs and improves localization accuracy.

Orbital advantages of Galileo G2 enhance triangulation precision.

Abstract

The accurate localization of gamma-ray bursts remains a crucial task. While historically, improved localization have led to the discovery of afterglow emission and the realization of their cosmological distribution via redshift measurements, a more recent requirement comes with the potential of studying the kilonovae of neutron star mergers. Gravitational wave detectors are expected to provide locations to not better than 10 square degrees over the next decade. With their increasing horizon for merger detections also the intensity of the gamma-ray and kilonova emission drops, making their identification in large error boxes a challenge. Thus, a localization via the gamma-ray emission seems to be the best chance to mitigate this problem. Here we propose to equip some of the second generation Galileo satellites with dedicated GRB detectors. This saves costs for launches and satellites for a dedicated GRB network, the large orbital radius is beneficial for triangulation, and perfect positional and timing accuracy come for free. We present simulations of the triangulation accuracy, demonstrating that short GRBs as faint as GRB 170817A can be localized to 1 degree radius (1 sigma).