Asteroseismology of old open clusters with Kepler: direct estimate of the integrated red giant branch mass-loss in NGC 6791 and 6819
Asteroseismology of old open clusters with Kepler: direct estimate of the integrated red giant branch mass-loss in NGC 6791 and 6819
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DOI：
10.1111/j.1365-2966.2011.19859.x
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发表时间：
2011-09
影响因子：
4.8
通讯作者：
A. Miglio;K. Brogaard;D. Stello;W. Chaplin;F. D’Antona;J. Montalbán;S. Basu;A. Bressan;A. Bressan;F. Grundahl;M. Pinsonneault;A. Serenelli;Y. Elsworth;S. Hekker;S. Hekker;T. Kallinger;B. Mosser;P. Ventura;A. Bonanno;A. Noels;V. S. Aguirre;R. Szabó;Jie Li;S. McCauliff;C. Middour;H. Kjeldsen
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文献类型：
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作者：
A. Miglio;K. Brogaard;D. Stello;W. Chaplin;F. D’Antona;J. Montalbán;S. Basu;A. Bressan;A. Bressan;F. Grundahl;M. Pinsonneault;A. Serenelli;Y. Elsworth;S. Hekker;S. Hekker;T. Kallinger;B. Mosser;P. Ventura;A. Bonanno;A. Noels;V. S. Aguirre;R. Szabó;Jie Li;S. McCauliff;C. Middour;H. Kjeldsen
红巨星分支（RGB）恒星的质量损失仍然很难确定，尽管它在星系的化学富集中起着至关重要的作用。由于开普勒望远镜最近探测到疏散星团中G-K巨星的类太阳振荡，我们现在可以直接确定旧疏散星团NGC 6791和6819中具有统计意义的恒星样本的恒星质量。这项工作的目的是通过比较红团（RC）中恒星的平均质量与RGB低光度部分的恒星（即具有L L（RC）的恒星）的平均质量来限制积分RGB质量损失。恒星的质量是通过结合可用的地震参数νmax和ν v与额外的光度限制和独立的距离估计来确定的。我们测量了旧的富金属星系团NGC 6791的RGB上40颗恒星和RC中19颗恒星的质量。我们发现RGB星和RC星的平均质量差别很小，但有显著性[M = 0.09 ± 0.03（随机）±0.04（系统）]
Mass-loss of red giant branch (RGB) stars is still poorly determined, despite its crucial role in the chemical enrichment of galaxies. Thanks to the recent detection of solar-like oscillations in G–K giants in open clusters with Kepler, we can now directly determine stellar masses for a statistically significant sample of stars in the old open clusters NGC 6791 and 6819. The aim of this work is to constrain the integrated RGB mass-loss by comparing the average mass of stars in the red clump (RC) with that of stars in the low-luminosity portion of the RGB [i.e. stars with L L(RC)]. Stellar masses were determined by combining the available seismic parameters νmax and �ν with additional photometric constraints and with independent distance estimates. We measured the masses of 40 stars on the RGB and 19 in the RC of the old metal-rich cluster NGC 6791. We find that the difference between the average mass of RGB and RC stars is small, but significant [� M = 0.09 ± 0.03 (random) ±0.04 (systematic)