Speaker
Description
We investigate the impact of thermonuclear X-ray bursts on the persistent emission of the low-mass X-ray binary 4U 1636–536. Archival observations from XMM-Newton and INTEGRAL were analyzed through time-resolved X-ray spectroscopy of a burst simultaneously detected by four instruments: EPIC-pn, RGS, JEM-X, and ISGRI. The persistent emission was modeled using a combination of accretion disk, Comptonization, and reflection components, while the burst emission was described by an additional blackbody component. We explore possible variations in the persistent emission adding a multiplicative scaling factor to the persistent emission model across all time intervals. Our results show a significant increase in the persistent emission during the burst. This behaviour is consistent with a temporary increase in the mass accretion rate, potentially driven by Poynting–Robertson drag induced by the burst radiation field. Additional spectral parameters, including luminosity, blackbody temperature, and flux, display coherent temporal evolution throughout the event. These findings support the scenario in which thermonuclear X-ray bursts can directly influence the accretion flow in neutron star low-mass X-ray binaries. We finally use our modelled evolution to simulate the time-resolved spectra during thermonuclear X-ray bursts of 4U 1636-536 as seen by NewAthena.
