X-ray Polarimetry as a Tool to Constrain Orbital Parameters in X-Ray Binaries

John Rankin; Vadim Kravtsov; Fabio Muleri; Juri Poutanen; Frédéric Marin; Fiamma Capitanio; Giorgio Matt; Enrico Costa; Alessandro Di Marco; Sergio Fabiani; Fabio La Monaca; Lorenzo Marra; Paolo Soffitta

arXiv · 2312.16967

X-ray Polarimetry as a Tool to Constrain Orbital Parameters in X-Ray Binaries

John Rankin·Vadim Kravtsov·Fabio Muleri·Juri Poutanen·Frédéric Marin·Fiamma Capitanio·Giorgio Matt·Enrico Costa·Alessandro Di Marco·Sergio Fabiani·Fabio La Monaca·Lorenzo Marra·Paolo Soffitta

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Abstract

X-ray binary systems consist of a companion star and a compact object in close orbit. Thanks to their copious X-ray emission, these objects have been studied in detail using X-ray spectroscopy and timing. The inclination of these systems is a major uncertainty in the determination of the mass of the compact object using optical spectroscopic methods. In this paper, we present a new method to constrain the inclination of X-ray binaries, which is based on the modeling of the polarization of X-rays photons produced by a compact source and scattered off the companion star. We describe our method and explore the potential of this technique in the specific case of the low mass X-ray binary GS 1826-238 observed by the Imaging X-ray Polarimetry Explorer (IXPE) observatory.

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John Rankin, Vadim Kravtsov, Fabio Muleri, Juri Poutanen, Frédéric Marin, Fiamma Capitanio, Giorgio Matt, Enrico Costa, Alessandro Di Marco, Sergio Fabiani, Fabio La Monaca, Lorenzo Marra, Paolo Soffitta. 2023-12-28. X-ray Polarimetry as a Tool to Constrain Orbital Parameters in X-Ray Binaries. https://arxiv.org/abs/2312.16967

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