Helium Nova on a Massive White Dwarf
نویسندگان
چکیده
The 2000 outburst of V445 Puppis shows unique properties, such as absence of hydrogen, enrichment of helium and carbon, 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 helium novae. 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 M⊙. The companion star is possibly either a helium star or a helium-rich main-sequence star. We estimate the ignition mass as several times 10M⊙, the corresponding helium accretion rate as several times 10 M⊙ yr , 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. Subject headings: binaries:close — novae — stars:individual (V445 Puppis) — —white dwarfs
منابع مشابه
Helium Nova on a Very Massive White Dwarf – a Light Curve Model of V445 Puppis (2000) Revised
V445 Pup (2000) is a unique object identified as a helium nova. Color indexes during the outburst are consistent with those of free-free emission. We present a free-free emission dominated light curve model of V445 Pup on the basis of the optically thick wind theory. Our light curve fitting shows that (1) the white dwarf (WD) mass is very massive (MWD & 1.35 M⊙), and (2) a half of the accreted ...
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