New Abundance Determinations of Cadmium, Lutetium, and Osmium in the R-Process Enriched Star BD+17 3248

Access full-text files

2010_05_Roederer.pdf (431.51 KB)

Date

2010-05

Authors

Roederer, Ian U.
Sneden, Christopher
Lawler, James E.
Cowan, John J.

Journal Title

Journal ISSN

Volume Title

Publisher

Abstract

We report the detection of Cd I (Z = 48), Lu II (Z = 71), and Os II (Z = 76) in the metal-poor star BD + 17 3248. These abundances are derived from an ultraviolet spectrum obtained with the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. This is the first detection of these neutron-capture species in a metal-poor star enriched by the r process. We supplement these measurements with new abundances of Moi, Rui, and Rh i derived from an optical spectrum obtained with the High Resolution Echelle Spectrograph on Keck. Combined with previous abundance derivations, 32 neutron-capture elements have been detected in BD + 17 3248, the most complete neutron-capture abundance pattern in any metal-poor star to date. The light neutron-capture elements (38 <= Z <= 48) show a more pronounced even-odd effect than expected from current solar system r-process abundance predictions. The age for BD + 17 3248 derived from the Th ii/Os II chronometer is in better agreement with the age derived from other chronometers than the age derived from Th ii/Os i. NewHf II abundance derivations from transitions in the ultraviolet are lower than those derived from transitions in the optical, and the lower Hf abundance is in better agreement with the scaled solar system r-process distribution.

Department

Astronomy

Description

Keywords

nuclear reactions, nucleosynthesis, abundances, stars: abundances, stars: individual (bd+17 3258, hd 122563), stars: population ii, metal-poor stars, laboratory transition-probabilities, theoretical, radiative lifetimes, neutron-capture elements, giant branch stars, oscillator-strengths, early galaxy, astrophysical interest, heavy-elements, process-rich, astronomy & astrophysics

LCSH Subject Headings

Citation

Roederer, Ian U., Christopher Sneden, James E. Lawler, and John J. Cowan. "NEW ABUNDANCE DETERMINATIONS OF CADMIUM, LUTETIUM, AND OSMIUM IN THE r-PROCESS ENRICHED STAR BD+ 17 3248Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs 8111 and 8342., Some of the data presented herein were obtained at the WM Keck Observatory, which is operated as a ...." The Astrophysical Journal Letters, Vol. 714, No. 1 (May, 2010): L123.

URI

http://hdl.handle.net/2152/42957

Collections

UT Faculty/Researcher Works