2018ApJ...860..147M

Type-I X-ray burst light curves encode unique information about the structure of accreting neutron stars and the nuclear reaction rates of the rp-process that powers bursts. Using the first model calculations of hydrogen/helium-burning bursts for a large range of astrophysical conditions performed with the code MESA, this work shows that simultaneous model-observation comparisons for bursts from several accretion rates {dot}M are required to remove degeneracies in astrophysical conditions that otherwise reproduce bursts for a single {dot}M and that such consistent multi-epoch modeling could possibly limit the ¹⁵O(α, γ)¹⁹Ne reaction rate. Comparisons to the 1998, 2000, and 2007 bursting epochs of the neutron star GS 1826-24 show that {dot}M must be larger than previously inferred and that the shallow heating in this source must be below 0.5 MeV/u, providing a new method to constrain the shallow heating mechanism in the outer layers of accreting neutron stars. Features of the light curve rise are used to demonstrate that a lower limit could likely be placed on the ¹⁵O(α, γ) reaction rate, demonstrating the possibility of constraining nuclear reaction rates with X-ray burst light curves.