A new URCA process

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

22

Electron Capture, Massive Stars, Nuclear Fusion, Radioactive Decay, Silicon, Abundance, Electron Decay Rate, Stellar Composition, Supernovae

Scientific paper

In the course of a general study of electron capture and beta-decay rates on fp shell nuclei which are abundant after core silicon burning in massive stars, we have found that the Fuller, Fowler, and Newman beta-decay rates are much stronger than generally has been realized. In fact, they can balance the capture rates during the conditions which are prevalent after core silicon burning, resulting in a new Urca process. The strength of the beta-decay rates is a result of thermal population of the Gamow-Teller back resonance in the parent nucleus and the behavior of beta-decay and electron capture Q-values for ensembles of nuclei in nuclear statistical equilibrium. All beta-decay rate tabulations prior to Fuller, Fowler, and Newman neglected the contribution of back resonances and thus drastically underestimated the overall rate. We use a simple analytic model to explain this balancing. The full rates are coupled to a nuclear statistical equilibrium code to demonstrate the strength of the decays. One zone models are used to examine, in a self-consistent fashion, how these rates could affect the presupernova evolution of the iron core and hence the core collapse problem.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

A new URCA process 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 A new URCA process, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A new URCA process will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1870938

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.