V445 Puppis: Helium Nova on a Massive White Dwarf
Abstract
The 2000 outburst of V445 Puppis shows unique properties, such as the absence of hydrogen, the enrichment of helium and carbon, and the slow development of the light curve with a small amplitude that does not resemble any classical novae. This object has been suggested to be the first example of a helium nova. We calculate theoretical light curves of helium novae and reproduce the observational light curve of V445 Pup. Modeling indicates a very massive white dwarf (WD), more massive than 1.3 Msolar. The companion star is possibly either a helium star or a helium-rich main-sequence star. We estimate the ignition mass as several times 10-5 Msolar, the corresponding helium accretion rate as several times 10-7 Msolar yr-1, and the recurrence period as several tens of years. These values suggest that the WD is growing in mass and ends up either a Type Ia supernova or an accretion-induced collapse to a neutron star.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 2003
- DOI:
- 10.1086/380597
- arXiv:
- arXiv:astro-ph/0310351
- Bibcode:
- 2003ApJ...598L.107K
- Keywords:
-
- Stars: Binaries: Close;
- Stars: Novae;
- Cataclysmic Variables;
- Stars: Individual: Constellation Name: V445 Puppis;
- Stars: White Dwarfs;
- Astrophysics
- E-Print:
- 6 pages including 3 figures, to appear in ApJL