Abundances in Metal-Poor Stars and Chemical Evolution of the Early Galaxy

Details Abundances in Metal-Poor Stars and Chemical Evolution of the Early Galaxy Abundances in Metal-Poor Stars and Chemical Evolution of the Early Galaxy

2008-09-16

arxiv.org/abs/0809.2827v1

Astronomy and Astrophysics

Astrophysics

5 pages, 3 figures, contributed talk given at the 10th Symposium on Nuclei in the Cosmos

Scientific paper

We have attributed the elements from Sr through Ag in stars of low metallicities ([Fe/H] < -1.5) to charged-particle reactions (CPR) in neutrino-driven winds, which are associated with neutron star formation in low-mass and normal supernovae (SNe) from progenitors of ~ 8 to 11 M_sun and ~ 12 to 25 M_sun, respectively. Using this rule and attributing all Fe production to normal SNe, we previously developed a phenomenological two-component model, which predicts that [Sr/Fe] > -0.32 for all metal-poor stars. This is in direct conflict with the high-resolution data now available, which show that there is a great shortfall of Sr relative to Fe in many stars with [Fe/H] < -3. The same conflict also exists for the CPR elements Y and Zr. We show that the data require a stellar source leaving behind black holes and that hypernovae (HNe) from progenitors of ~ 25 to 50 M_sun are the most plausible candidates. If we expand our previous model to include three components (low-mass and normal SNe and HNe), we find that essentially all of the data are very well described by the new model. The HN yield pattern for the low-A elements from Na through Zn (including Fe) is inferred from the stars deficient in Sr, Y, and Zr. We estimate that HNe contributed ~ 24% of the bulk solar Fe inventory while normal SNe contributed only ~ 9% (not the usually assumed ~ 33%). This implies a greatly reduced role of normal SNe in the chemical evolution of the low-A elements.

Affiliated with

Also associated with

No associations

Rating

Abundances in Metal-Poor Stars and Chemical Evolution of the Early Galaxy 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 Abundances in Metal-Poor Stars and Chemical Evolution of the Early Galaxy, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Abundances in Metal-Poor Stars and Chemical Evolution of the Early Galaxy will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-661131