Beryllium abundance in turn-off stars of NGC 6752

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Beryllium abundance in turn-off stars of NGC 6752

Aims. To measure the beryllium abundance in two TO stars of the Globular Cluster NGC 6752, one oxygen rich and sodium poor, the other presumably oxygen poor and sodium rich. Be abundances in these stars are used to put on firmer grounds the hypothesis of Be as cosmochronometer and to investigate the formation of Globular Clusters. Methods. We present near UV spectra with resolution R∼ 45000 obt...

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ژورنال

عنوان ژورنال: Astronomy & Astrophysics

سال: 2007

ISSN: 0004-6361,1432-0746

DOI: 10.1051/0004-6361:20066260