A Universal Decline Law of Classical Novae. Iv. V838 Her (1991): a Very Massive White Dwarf
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چکیده
We present a unified model of optical and ultraviolet (UV) light curves for one of the fastest classical novae, V838 Herculis (Nova Herculis 1991), and estimate its white dwarf (WD) mass. Based on an optically thick wind theory of nova outbursts, we model the optical light curves with free-free emission and the UV 1455 Å light curves with blackbody emission. Our models of 1.35 ± 0.02 M⊙ WD reproduce simultaneously the optical and UV 1455 Å observations. The mass lost by the wind is ∆ Mwind ∼ 2× 10 −6 M⊙. We provide new determinations of the reddening, E(B − V ) = 0.53± 0.05, and of the distance, 2.7± 0.5 kpc. Subject headings: — nova, cataclysmic variables — stars: individual (V838 Herculis) — stars: mass loss — ultraviolet: stars — white dwarfs
منابع مشابه
Recurrent Novae , Classical Novae , Symbiotic Novae , and Population II
Light curve analysis of decay phase of nova outburst are summarized. Nova duration is determined by the strong wind mass-loss which depends only on the white dwarf mass. Fast novae correspond very massive white dwarfs and very slow novae correspond almost lower mass limit of white dwarfs. This relation is shown in both of classical novae and recurrent novae. Light curves are theoretically repro...
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تاریخ انتشار 2009