# Gamma-ray burst localisation strategies for the SPHiNX hard X-ray polarimeter

## TL;DR

This paper explores how the SPHiNX gamma-ray burst polarimeter can localize GRB positions using simulations, ensuring high polarisation sensitivity for most observed GRBs despite localization uncertainties.

## Contribution

It demonstrates the feasibility of localizing GRBs with a few degrees accuracy using three routines, maintaining polarisation sensitivity for over 80% of observed bursts.

## Key findings

- Localization at a few degrees is achievable with three routines.
- Over 80% of GRBs have less than 5% sensitivity reduction due to localization uncertainty.
- Simulations confirm the stand-alone localization capability of SPHiNX.

## Abstract

SPHiNX is a proposed gamma-ray burst (GRB) polarimeter mission operating in the energy range 50-600 keV with the aim of studying the prompt emission phase. The polarisation sensitivity of SPHiNX reduces as the uncertainty on the GRB sky position increases. The stand-alone ability of the SPHiNX design to localise GRB positions is explored via Geant4 simulations. Localisation at the level of a few degrees is possible using three different routines. This results in a large fraction (> 80%) of observed GRBs having a negligible (< 5%) reduction in polarisation sensitivity due to the uncertainty in localisation.