Beryllium in turnoff stars of NGC 6397: Early Galaxy spallation, cosmochronology and cluster formation
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چکیده
منابع مشابه
Beryllium in turnoff stars of NGC 6397 : early Galaxy spallation , cosmochronology and cluster formation ⋆
We present the first detection of beryllium in two turnoff stars of the old, metal-poor globular cluster NGC 6397. The beryllium lines are clearly detected and we determine a mean beryllium abundance of log(Be/H)= −12.35± 0.2. The beryllium abundance is very similar to that of field stars of similar Fe content. We interpret the beryllium abundance observed as the result of primary spallation of...
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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: 2004
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20041254