We present our first results from one-dimensional, multizone calculations of unstable H/He burning in the envelopes of accreting neutron stars. Rapid proton captures (rp-process) onto heavy isotopes may be responsible for the long tails observed from some type I X-ray bursts, and the composition of the ashes determines the amount of fuel availiable for subsequent bursts as well as the thermal and mechanical properties of the neutron star crust. To capture this rp-process nucleosynthesis, our thermonuclear reaction network extends to xenon. The multizone calculations elucidate how the convective transport of both heat and matter affect the light curve and post-burst composition. We also explore the effects of the accretion rate, composition of the accreted material, and surface gravity of the neutron star.This work is supported by the Department of Energy under grant B341495 to the Center for Astrophysical Thermonuclear Flashes at the University of Chicago.
AAS/High Energy Astrophysics Division #7
- Pub Date:
- March 2003