Stellar Abundance Observations and Heavy Element Formation

Details Stellar Abundance Observations and Heavy Element Formation Stellar Abundance Observations and Heavy Element Formation

May 2005

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005aas...206.5001c&link_type=abstract

American Astronomical Society Meeting 206, #50.01; Bulletin of the American Astronomical Society, Vol. 37, p.504

Astronomy and Astrophysics

Astronomy

Scientific paper

Abundance observations indicate the presence of rapid-neutron capture (i.e., r-process) elements in old Galactic halo and globular cluster stars. These observations provide insight into the nature of the earliest generations of stars in the Galaxy -- the progenitors of the halo stars -- responsible for neutron-capture synthesis of the heavy elements. Abundance comparisons among the r-process-rich halo stars show that the heaviest neutron-capture elements (i.e., Ba and above) are consistent with a scaled solar system r-process abundance distribution, while the lighter neutron-capture elements do not conform to the solar pattern. These comparisons suggest the possibility of two r-process sites in stars. The large star-to-star scatter observed in the abundances of neutron-capture element/iron ratios at low metallicities -- which disappears with increasing metallicity or [Fe/H] -- suggests the formation of these heavy elements (presumably from certain types of supernovae) was rare in the early Galaxy. The stellar abundances also indicate a change from the r-process to the slow neutron capture (i.e., s-) process at higher metallicities in the Galaxy and provide insight into Galactic chemical evolution. Finally, the detection of thorium and uranium in halo and globular cluster stars offers an independent age-dating technique that can put lower limits on the age of the Galaxy, and hence the Universe.
This work has been supported in part by NSF grant AST 03-07279 (J.J.C.) and by STScI grants GO-8111, GO-8342 and GO-9359.

Affiliated with

Also associated with

No associations

Rating

Stellar Abundance Observations and Heavy Element Formation 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 Stellar Abundance Observations and Heavy Element Formation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stellar Abundance Observations and Heavy Element Formation will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1687610