The effects of new nuclear reaction rates and opacities on hydrodynamic simulations of the nova outburst

Sumner Starrfield, W. M. Sparks, J. W. Truran, M. C. Wiescher

Research output: Contribution to journalArticle

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Abstract

We report on the results of new calculations of thermonuclear runaways on 1.25 M oxygen, neon, and magnesium white dwarfs, using our one-dimensional, fully implicit, hydrodynamic stellar evolution code that includes a large nuclear reaction network. We have updated the nuclear reaction network by including both new and improved experimental and theoretical determinations of the nuclear reaction rates. We have also incorporated the carbon-rich OPAL opacity tables. Our results show that the changes in the reaction rates and opacities that we have introduced produce important changes with respect to our previous studies. For example, a smaller amount of 26Al is produced, while the abundances of 31P and 32S increase by factors of more than 2. This change is attributed to the increased proton-capture reaction rates for some of the intermediate-mass nuclei near 26Al and beyond, such that nuclear fusion to higher mass nuclei is enhanced. We also find that our predicted values for the amount of mass ejected in the outburst are at least a factor of 10 less than observed. The low values for the amount of ejected mass is a consequence of the fact that the OPAL opacities are larger than those we previously used, which results in more heat being trapped in the nuclear-burning regions and, therefore, less mass being accreted onto the white dwarf.

Original languageEnglish (US)
Pages (from-to)485-495
Number of pages11
JournalAstrophysical Journal, Supplement Series
Volume127
Issue number2
DOIs
StatePublished - Apr 2000

Fingerprint

opacity
nuclear reactions
outburst
reaction rate
reaction kinetics
hydrodynamics
simulation
nuclei
neon
stellar evolution
nuclear fusion
magnesium
nuclear reaction
effect
heat
oxygen
protons
carbon

Keywords

  • Hydrodynamics
  • Novae, cataclysmic variables
  • Nuclear reactions, nucleosynthesis, abundances
  • White dwarf

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

The effects of new nuclear reaction rates and opacities on hydrodynamic simulations of the nova outburst. / Starrfield, Sumner; Sparks, W. M.; Truran, J. W.; Wiescher, M. C.

In: Astrophysical Journal, Supplement Series, Vol. 127, No. 2, 04.2000, p. 485-495.

Research output: Contribution to journalArticle

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