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arXiv · 1901.08948

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

L. Heckmann·N. K. Iyer·M. Kiss·M. Pearce·F. Xie
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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.

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L. Heckmann, N. K. Iyer, M. Kiss, M. Pearce, F. Xie. 2019-01-25. Gamma-ray burst localisation strategies for the SPHiNX hard X-ray polarimeter. https://doi.org/10.1117/1.jatis.5.1.018002

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