Nucleosynthesis and the nova outburst

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:206881

Starrfield, S ^[1]; Truran, J W ^[2]; Wiescher, M ^[3]; Sparks, W M ^[4]

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1. Arizona State Univ., Tempe, AZ (United States). Dept. of Physics and Astronomy
2. Chicago Univ., IL (United States). Enrico Fermi Inst.
3. Notre Dame Univ., IN (United States). Dept. of Physics
4. Los Alamos National Lab., NM (United States)

A nova outburst is the consequence of the accretion of hydrogen rich material onto a white dwarf and it can be considered as the largest hydrogen bomb in the Universe. The fuel is supplied by a secondary star in a close binary system while the strong degeneracy of the massive white dwarf acts to contain the gas during the early stages of the explosion. The containment allows the temperature in the nuclear burning region to exceed 10{sup 8}K under all circumstances. As a result a major fraction of CNO nuclei in the envelope are transformed into {beta}{sup +}-unstable nuclei. We discuss the effects of these nuclei on the evolution. Recent observational studies have shown that there are two compositional classes of novae; one which occurs on carbon-oxygen white dwarfs, and a second class that occurs on oxygen-neon-magnesium white dwarfs. In this review we will concentrate on the latter explosions since they produce the most interesting nucleosynthesis. We report both on the results of new observational determinations of nova abundances and, in addition, new hydrodynamic calculations that examine the consequences of the accretion process on 1.0M{sub {circle_dot}}, 1.25M{sub {circle_dot}}, and 1.35M{sub {circle_dot}} white dwarfs. Our results show that novae can produce {sup 22}Na, {sup 26}Al, and other intermediate mass nuclei in interesting amounts. We will present the results of new calculations, done with updated nuclear reaction rates and opacities, which exhibit quantitative differences with respect to published work.

• Research Organization: Los Alamos National Lab., NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States); National Science Foundation, Washington, DC (United States); National Aeronautics and Space Administration, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 206881
• Report Number(s): LA-UR--95-4462; CONF-9510331--1; ON: DE96007251
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ALUMINIUM 26
HYDROGEN BURNING
MAGNESIUM
MASS TRANSFER
NEON
NOVA MODEL
NUCLEOSYNTHESIS
OXYGEN
SODIUM 22
WHITE DWARF STARS