Details

Autor(en) / Beteiligte

• Placco, Vinicius M.
• Holmbeck, Erika M.
• Frebel, Anna
• Beers, Timothy C.
• Surman, Rebecca A.
• Ji, Alexander P.
• Ezzeddine, Rana
• Points, Sean D.
• Kaleida, Catherine C.
• Hansen, Terese T.
• Sakari, Charli M.
• Casey, Andrew R.

Titel

RAVE J203843.2–002333: The First Highly R-process-enhanced Star Identified in the RAVE Survey

Ist Teil von

• The Astrophysical journal, 2017-07, Vol.844 (1), p.18

Ort / Verlag

Philadelphia: IOP Publishing

Erscheinungsjahr

2017

Link zum Volltext

Quelle

EZB Free E-Journals

Beschreibungen/Notizen

• Abstract We report the discovery of RAVE J203843.2−002333, a bright ( V = 12.73), very metal-poor ( = −2.91), r -process-enhanced ( = +1.64 and = −0.81) star selected from the RAVE survey. This star was identified as a metal-poor candidate based on its medium-resolution ( R ∼ 1600) spectrum obtained with the KPNO/Mayall Telescope, and followed up with high-resolution ( R ∼ 66,000) spectroscopy with the Magellan /Clay Telescope, allowing for the determination of elemental abundances for 24 neutron-capture elements, including thorium and uranium. RAVE J2038−0023 is only the fourth metal-poor star with a clearly measured U abundance. The derived chemical abundance pattern exhibits good agreement with those of other known highly r -process-enhanced stars, and evidence suggests that it is not an actinide-boost star. Age estimates were calculated using U/X abundance ratios, yielding a mean age of 13.0 ± 1.1 Gyr.