Physics – Nuclear Physics
Scientific paper
Oct 2002
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2002aps..dnp.cf005o&link_type=abstract
American Physical Society, 2002 Fall Meeting of the Division of Nuclear , abstract #CF.005
Physics
Nuclear Physics
Scientific paper
We review recent observational and theoretical results concerning the presence of actinide nuclei on the surfaces of old halo stars and their use as an age determinant. We present evidence that the observed universality of abundances for 56 <= Z <= 70 nuclei does not imply a unique astrophysical site for the r-process. Neither does it imply a universality of abundances of nuclei lighter or heavier than this range. In particular, we show that a variety of astrophysical r-process models can be constructed which reproduce the observed universal r-process curve for 56 <= Z <= 70 nuclei, yet have vastly different abundances for Z > 70 and Z < 56 nuclei. This introduces an uncertainty into the use of the Th/Eu chronometer as a means to estimate the ages of the metal deficient stars. We do find, however, that the U/Th ratio is a robust chronometer. This is because the initial production ratio of U to Th is almost independent of astrophysical nucleosynthesis environment. The largest remaining uncertainties in the U/Th initial production ratio are due to the input nuclear physics models. We argue that new observational data might be used to constrain these nuclear physics uncertainties.
Mathews Grant J.
Otsuki Kaori
No associations
LandOfFree
Cosmochronology and universality of r-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 Cosmochronology and universality of r-process, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cosmochronology and universality of r-process will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1660957