CNO abundances and the strengths of nova outbursts and hydrogen flashes on accreting white dwarfs

Abstract

view Abstract Citations (140) References (85) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS CNO abundances and the strengths of nova outbursts and hydrogen flashes on accreting white dwarfs. MacDonald, J. Abstract Simple theories of the accretion phase and expansion phase of hydrogen shell flashes on accreting white dwarfs are used to find the conditions under which classical novae occur. Particular attention is paid to the possibility that the CNO abundances in the accreted envelope are greatly enhanced relative to the Sun. It is shown that such an enhancement is necessary for fast novae, yet slow novae, such as DQ Her, can still occur with large CNO enhancements. An analysis of the observed properties of nova ejecta indicates that the white dwarfs in nova systems have masses in the range 1.02-1.18 Msun. It is found that in some novae, including RR Pic, CP Lac, and V603 Aql, the accretion rate deduced from the optical luminosity in quiescence is too high to allow accretion of sufficient envelope material to get the strong hydrogen flash needed for the nova outburst. Some possible resolutions of this problem are discussed. We also find it unlikely that recurrent novae are thermonuclear runaways on accreting white dwarfs. Publication: The Astrophysical Journal Pub Date: April 1983 DOI: 10.1086/160911 Bibcode: 1983ApJ...267..732M Keywords: Abundance; Novae; Stellar Mass Accretion; Stellar Models; White Dwarf Stars; Carbon; Nitrogen Atoms; Nuclear Fusion; Oxygen Atoms; Stellar Envelopes; Astrophysics full text sources ADS | data products SIMBAD (9)