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arXiv · 2210.03598

Robust inference of neutron-star parameters from thermonuclear burst observations

D. K. Galloway·Z. Johnston·A. J. Goodwin·C. -C. He
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Abstract

Thermonuclear (type-I) bursts arise from unstable ignition of accumulated fuel on the surface of neutron stars in low-mass X-ray binaries. Measurements of burst properties in principle enable observers to infer the properties of the host neutron star and mass donors, but a number of confounding astrophysical effects contribute to systematic uncertainties. Here we describe some commonly-used approaches for determining system parameters, including composition of the burst fuel, and introduce a new suite of software tools, concord, intended to fully account for astrophysical uncertainties. Comparison of observed burst properties with the predictions of numerical models is a complementary method of constraining host properties, and the tools presented here are intended to make comprehensive model-observation comparisons straightforward. When combined with the extensive samples of burst observations accumulated by X-ray observatories, these software tools will provide a step-change in the amount of information that can be inferred about typical burst sources.

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D. K. Galloway, Z. Johnston, A. J. Goodwin, C. -C. He. 2022-10-07. Robust inference of neutron-star parameters from thermonuclear burst observations. https://doi.org/10.3847/1538-4365%2Fac98c9

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