Does the oxygen-sodium anticorrelation in globular clusters require a lowering of the 23Na(p,α)20Ne reaction rate?

Details Does the oxygen-sodium anticorrelation in globular clusters require a lowering of the 23Na(p,α)20Ne reaction rate? Does the oxygen-sodium anticorrelation in globular clusters require a lowering of the 23Na(p,α)20Ne reaction rate?

Oct 2006

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006a%26a...457..995v&link_type=abstract

Astronomy and Astrophysics, Volume 457, Issue 3, October III 2006, pp.995-1001

Astronomy and Astrophysics

Astrophysics

15

Stars: Abundances, Stars: Agb And Post-Agb, Stars: Evolution

Scientific paper

Context: .The chemical content of the ejecta of Asymptotic Giant Branch stars (AGBs) is important to understand whether intermediate mass stars played a role in the "self-enrichment scenario", to explain the chemical anomalies observed among Globular Clusters stars. One difficulty of this model is that it is not fully consistent with the observed oxygen-sodium anticorrelation. Aims: .We look for the combinations of the input-physics parameters by which the yields of massive AGBs are sodium-rich and oxygen-poor. Methods: .Many evolutions from the early evolutionary phases until the mass of the envelope drops below ~0.5~M&sun; are calculated for a 5~M&sun; Z=0.001 model for various assumptions concerning the extra mixing from the bottom of the envelope and the relevant cross sections involving sodium. Results: .A modest amount of extra mixing from the bottom of the surface convective zone leads to ejecta that are moderately sodium rich and oxygen depleted. A different but appealing modelization allows us to reproduce the observations of stars with a lower oxygen content: extra mixing is not included, but the cross sections of the reaction 23Na(p, α)20Ne must be a factor of ~4 lower than the recommended values. If the initial neon content of the star is not solar-scaled but enhanced as the other α elements by a factor ~2, the afore mentioned cross section must be lessened by only a factor ~2.

Affiliated with

Also associated with

No associations

Rating

Does the oxygen-sodium anticorrelation in globular clusters require a lowering of the 23Na(p,α)20Ne reaction rate? 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 Does the oxygen-sodium anticorrelation in globular clusters require a lowering of the 23Na(p,α)20Ne reaction rate?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Does the oxygen-sodium anticorrelation in globular clusters require a lowering of the 23Na(p,α)20Ne reaction rate? will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-867940