Astronomy and Astrophysics – Astrophysics – Solar and Stellar Astrophysics
Scientific paper
2011-07-08
Astronomy and Astrophysics
Astrophysics
Solar and Stellar Astrophysics
Proceedings of: Nuclear Physics in Astrophysics-V,Eilat,April,2011
Scientific paper
There is a wide consensus in the astrophysics community that the mechanism underlying the observed Classical Nova eruptions is a surface thermonuclear runaway. We start this short review with the main observational facts that lead to the theoretical model of a thermonuclear runaway that takes place in an accreted hydrogen rich envelope placed on top of a cool degenerate core of a white dwarf. According to the theory, the accreted envelope becomes unstable to convection days to weeks prior to the runaway. During the extreme stages of the runaway itself, when the burning is most efficient, the envelope is fully convective. Therefore, the elements processed under such extreme conditions are lifted to the outermost regions of the star. A significant fraction of the envelope is ejected during the outburst. The complicated combination of hydrodynamic instabilities and explosive hydrogen burning, close to the surface of the star, gives us a unique opportunity to study this complex reactive flow. The range of core masses, core temperatures and accretion rates introduce a whole range of burning temperatures and densities. Following the description of the "standard" cases, we then focus on rare, but still possible, portions of the relevant parameter space, in which "breakout" of the traditional CNO cycle can occur and lead to heavy element enrichment patterns caused only by breakout burning. We conclude our review with the main challenges that nova theorists face today, with special emphasis on problems related to the nucleosynthesis issues.
Glasner Ami S.
Truran Jame. W.
No associations
LandOfFree
Novae -The study of the reactive flow does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Novae -The study of the reactive flow, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Novae -The study of the reactive flow will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-221861