Superbursts and X-ray burst quenching on accreting neutron stars (Webinar Registration)
Laurens Keek, MSU
Abstract: Superburst are day-long X-ray flares observed from neutron stars, and are produced by runaway thermonuclear burning of carbon. They are rare, but they probe the star's interior, providing information about the neutron star crust. We discuss recent multi-zone numerical models, that simulate superbursts in detail on time scales from microseconds to years, and we compare these models to the scarce observations (http://iopscience.iop.org/0004-637X/743/2/189).
A superburst heats the atmosphere such that all hydrogen and helium burning becomes stable for a day to weeks. Only when the envelope cools down, does burning become unstable, and do short X-ray bursts return. We present detailed simulations of this transition of stable to unstable burning of hydrogen and helium after a superburst, and discuss the nuclear processes responsible for the different observable phenomena.