Article

Two- and Three-Dimensional Simulations of the Thermonuclear Runaway in an Accreted Atmosphere of a C+O White Dwarf

Lecture Notes in Physics 03/1999; DOI: 10.1007/BFb0106631
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ABSTRACT . We present the results of two- and three-dimensional calculations of turbulent nuclear burning of hydrogen-rich material accreted onto a white dwarf of 1.0 M fi . The main aim of the present paper is to investigate the question as to whether and how the general properties of the burning are affected by dimensionality and numerical resolution effects. In particular, we want to see whether or not convective overshooting into the surface layers of the C+O white dwarf can lead to self-enrichment of the initially solar composition of the hydrogen-rich envelope with carbon and oxygen from the underlying white dwarf core. 1 Introduction Today, we know that novae are white dwarfs in close binary systems with a main sequence star as their companion. The white dwarf collects hydrogenrich material from the companion which first settles into an accretion disk and is then accreted onto the white dwarf's surface. Due to compressional heating this envelope can reach temperatures sufficiently high...

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