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arXiv · 2206.00749

Polarization properties of weakly magnetized Neutron Stars in Low Mass X-ray Binaries

Andrea Gnarini·Francesco Ursini·Giorgio Matt·Stefano Bianchi·Fiamma Capitanio·Massimo Cocchi·Ruben Farinelli·Wenda Zhang
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Abstract

X-ray polarimetry missions like IXPE will be able to measure for the first time the polarization properties of accreting, weakly magnetized neutron stars in Low Mass X-ray Binaries. In this work we present simulations of the expected X-ray polarized signal including the coronal emission for different geometries of the corona itself, i.e. a slab above the accretion disc and a spherical shell around the neutron star. The simulations are performed with the fully relativistic Monte Carlo code monk capable of computing the X-ray polarization degree and angle for various physical input parameters of the neutron star, disc and corona. Different coronal geometries result in significantly different X-ray polarization properties, which can therefore be used to constrain the geometry of the systems.

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Andrea Gnarini, Francesco Ursini, Giorgio Matt, Stefano Bianchi, Fiamma Capitanio, Massimo Cocchi, Ruben Farinelli, Wenda Zhang. 2022-06-01. Polarization properties of weakly magnetized Neutron Stars in Low Mass X-ray Binaries. https://doi.org/10.1093/mnras/stac1523

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