Nuclear-dominated accretion and subluminous supernovae from the merger of a white dwarf with a neutron star or black hole

Understand

We construct one dimensional steady-state models of accretion disks produced by the tidal disruption of a white dwarf (WD) by a neutron star (NS) or stellar mass black hole (BH).

• At radii r <~ 1e8.5-1e9 cm the midplane density and temperature are sufficiently high to burn the initial white dwarf material into increasingly heavier elements (e.g.
• Mg, Si, S, Ca, Fe, and Ni) at sequentially smaller radii.
• When the energy released by nuclear reactions is comparable to that released gravitationally, we term the disk a nuclear-dominated accretion flow (NuDAF).