Science prospects for SPHiNX – a small satellite GRB polarimetry mission

M. Pearce, L. Eliasson, N. Kumar Iyer, M. Kiss, R. Kushwah, J. Larsson, C. Lundman, V. Mikhalev, F. Ryde, T.-A. Stana, H. Takahashi, F. Xie
(Submitted on 16 Aug 2018)

Gamma-ray bursts (GRBs) are exceptionally bright electromagnetic events occurring daily on the sky. The prompt emission is dominated by X-/$\gamma$-rays. Since their discovery over 50 years ago, GRBs are primarily studied through spectral and temporal measurements. The properties of the emission jets and underlying processes are not well understood. A promising way forward is the development of missions capable of characterising the linear polarisation of the high-energy emission. For this reason, the SPHiNX mission has been developed for a small-satellite platform. The polarisation properties of incident high-energy radiation (50-600 keV) are determined by reconstructing Compton scattering interactions in a segmented array of plastic and Gd$_3$Al$_2$Ga$_3$O$_{12}$(Ce) (GAGG(Ce)) scintillators. During a two-year mission, $\sim$200 GRBs will be observed, with $\sim$50 yielding measurements where the polarisation fraction is determined with a relative error $\leq$10%. This is a significant improvement compared to contemporary missions. This performance, combined with the ability to reconstruct GRB localisation and spectral properties, will allow discrimination between leading classes of emission models.

Comments:    Accepted for publication in Astroparticle Physics
Subjects:    Instrumentation and Methods for Astrophysics (astro-ph.IM)
Cite as:    arXiv:1808.05384 [astro-ph.IM] (or arXiv:1808.05384v1 [astro-ph.IM] for this version)
Submission history
From: Mark Pearce
[v1] Thu, 16 Aug 2018 09:25:10 GMT (2016kb,D)
https://arxiv.org/abs/1808.05384