Type I X-ray burst as a tool to probe the physics of neutron stars
Liu, Helei
Type I X-ray bursts are powered by unstable thermonuclear burning of accumulated hydrogen and helium on the surface of NS in a low-mass X-ray binary (LMXB). The burst phenomenon is related not only outside but also inside physics of neutron star (NS). As the numerical treatments of the accreting NS and physics of the NS interior are not established, which shows uncertainty in modelling for observed X-ray light curves. We focus on the impacts of NS mass, radius and base-heating on the NS surface using the MESA code. Meanwhile, the millihertz Quasi period oscillations (QPOs) in LMXB are studied using a one-zone X-ray burst model, the effects of surface gravity, helium mass fraction, base heating and metallicity are studied. It’s found that the high metallicity and large base heating, combined with a lower surface gravity and helium mass fraction, could be responsible for the observed critical mass accretion rate (\dot{m}≃0.3\dot{m}_{Edd}). We may infer the surface gravity if we known the oscillation frequency and mass accretion rate of mHz QPOs.