The Status of Multidimensional Models of Xray Bursts

Abstract:  Type I Xray Bursts (XRBs) have been the focus of relatively successful one-dimensional modeling efforts since their discovery in the mid-70's. The one-dimensional hydrodynamic models reproduce the general luminosities and timescales of the events; more recently, with larger nuclear reaction networks, the nucleosynthesis of the explosive rp-process during the burst has been investigated in detail. Prior to peak luminosity, there is a period of turbulent convection that the one-dimensional models can not accurately treat. Furthermore, ignition is thought to occur in a single location on the neutron star surface and spread around the star as indicated in oscillations in luminosity during the burst rise; again, something that one-dimensional models can not capture. In this talk, I'll give an overview of the multidimensional treatments of XRBs in the literature, including the challenges of low Mach number multidimensional hydrodynamics, the successes and the shortcomings of our current understanding. I will discuss some of our latest results with three-dimensional models and our plans for improvement on modern computer architectures.