Chemical compositions of four metal-poor giant stars

Citation
S. Giridhar et al., Chemical compositions of four metal-poor giant stars, PUB AST S P, 113(783), 2001, pp. 519-528
Citations number
25
Categorie Soggetti
Space Sciences
Journal title
PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC
ISSN journal
00046280 → ACNP
Volume
113
Issue
783
Year of publication
2001
Pages
519 - 528
Database
ISI
SICI code
0004-6280(200105)113:783<519:CCOFMG>2.0.ZU;2-8
Abstract
We present the chemical compositions of four K giants (CS 22877-1, CS 22166 -16, CS 22169-35, and BS 16085-0050) that have [Fe/H] in the range -2.4 to -3.1. Metal-poor stars with [Fe/H] < -2.5 are known to exhibit considerable star-to-star variations of many elements. This quartet confirms this concl usion. CS 22877-1 and CS 22166-16 are carbon-rich. There is significant spr ead of [<alpha>/Fe] within our samples, where [alpha /Fe] is computed from the mean of the [Mg/Fe] and [Ca/Fe] ratios. BS 16085-0050 is remarkably alp ha -enriched with a mean [alpha /Fe] of +0.7, but CS 22169-35 is alpha -poo r. The aluminum abundance also shows a significant variation over the sampl e. A parallel and unsuccessful search among high-velocity late-type stars f or metal-poor stars is described.