How oxygen affects the CMDs and predicted ages of extreme Population II stars

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

13

Scientific paper

Stellar evolutionary tracks, isochrones, and ZAHB loci have been constructed for [Fe/H]=-2.27 and four mixtures of the heavy elements to investigate how predicted C-M diagrams and age versus turnoff-luminosity relations are affected by varying the assumed abundance of oxygen (with and without enhancements in the other α-elements). These four mixes correspond to: (i) [m/H]=0.0; (ii) [m/H]=0.0, but [O/Fe]=0.3; (iii) [α/Fe]=0.3, all other metals in scaled-solar proportions; and (iv) [α/Fe]=0.3, but [O/Fe]=1.0. Model atmospheres and synthetic color-Teff relations were computed for each of these cases. In agreement with previous work, each increase of 0.3 dex in [O/Fe] implies a 1 Gyr age reduction at a fixed turnoff luminosity. Neither the location of the main sequence nor the position of the giant branch are affected significantly by a change in the O abundance, though the distribution of stellar masses on the horizontal branch is predicted to be quite sensitive to the adopted [O/Fe] value.

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

How oxygen affects the CMDs and predicted ages of extreme Population II stars 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 How oxygen affects the CMDs and predicted ages of extreme Population II stars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and How oxygen affects the CMDs and predicted ages of extreme Population II stars will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1204990

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