V445 Pup was discovered on 23 November 2000 and the evolution of its outburst has been followed since that time. It was realized almost immediately that it was an extremely unusual, if not unique, event since there were no hydrogen lines present in the spectrum. It never did show any hydrogen lines in the spectrum and the most prominent features were those of carbon with helium present at later times. It was suggested early on that it was an outburst caused by the accretion of helium onto a white dwarf: a helium nova. It was also suggested that not all the accreted material was ejected in the outburst so that the white dwarf was growing in mass and V445 Pup could be a Supernova Ia progenitor. We have now begun simulations of such an event using our one-dimensional hydrodynamic computer code, NOVA, that was most recently used for simulations of the outburst of RS Oph. We have followed the evolution of white dwarfs of 1 and 1.35 Solar masses accreting helium over a broad range of mass accretion rates and initial white dwarf luminosities. We will report both on our observations obtained early in the outburst and, in addition, on our preliminary calculations which imply that initial conditions and mass accretion rates typical of those used to simulate classical or recurrent nova outbursts and observed in Cataclysmic Variables do not result in simulations that reproduce the outburst of V445 Pup.We gratefully acknowledge support from the NSF, NASA and DOE.
American Astronomical Society Meeting Abstracts #215
- Pub Date:
- January 2010