A ``Quick Survey'' for Halo Giants with [Fe/H] ≤ -2.5

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

We propose to continue our accelerated search for giants in the halo of the Milky Way with [Fe/H] ≤ -2.5. Our primary motivation for this search are the recent discoveries of several additional ``r-process- enhanced'' stars, similar to the previously unique example of the phenomenon, CS 22892-052 (there are now four known). These stars exhibit r-process/Fe elemental ratios in excess of 30-50 times solar values, and all possess measurable lines of the radioactive species thorium, from which lower limits of the age of the Galaxy can be made. Several of the newly discovered r-process enhanced stars we seek may exhibit measurable U lines. However, it has also become clear that the U and Th abundances in one such star, CS 31082-001, are about 0.4 dex higher than other examples of the phenomenon, indicating that our understanding of the operation of the r-process beyond the third r- process peak remains incomplete. Hence, in order to make full use of such stars for cosmochronology, substantially larger samples of these stars are required. High-resolution studies of ~ 300-500 such stars, already underway with the VLT (159 hours in present semester/ similar allocations expected over next 3 semesters), will yield new detections of some 10-15 highly r-process-enhanced stars (and perhaps larger numbers of moderately r-process-enhanced stars), opening the door to detailed understanding of the r-process, as well as providing a plethora of stars useful for cosmochronology.

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

A ``Quick Survey'' for Halo Giants with [Fe/H] ≤ -2.5 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 A ``Quick Survey'' for Halo Giants with [Fe/H] ≤ -2.5, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A ``Quick Survey'' for Halo Giants with [Fe/H] ≤ -2.5 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-912161

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