MUSE crowded field 3D spectroscopy of over 12 000 stars in the globular cluster NGC 6397 - I. The first comprehensive HRD of a globular cluster
MUSE crowded field 3D spectroscopy of over 12 000 stars in the globular cluster NGC 6397 - I. The first comprehensive HRD of a globular cluster
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对球状星团 NGC 6397 - I 中超过 12 000 颗恒星的 MUSE 拥挤场 3D 光谱。第一个球状星团的综合 HRD
DOI：
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
A. Monreal
中科院分区：
文献类型：
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作者：
T. Husser;S. Kamann;S. Dreizler;M. Wendt;Nina Wulff;R. Bacon;L. Wisotzki;J. Brinchmann;P. Weilbacher;M. Roth;A. Monreal
目标。通过对球状星团NGC 6397中12000多颗恒星的光谱分析，我们证明了利用新的积分场摄谱仪MUSE进行拥挤场3D光谱分析的高复用优势。方法.恒星的点扩散函数拟合技术进行去混合，使用测光参考目录从HST作为前，包括相对位置和亮度。该目录还用于提取光谱的第一次分析，然后通过基于PHOENIX光谱大网格的全光谱拟合方法进行自动深入分析。结果我们分析了NGC 6397中12307颗恒星的18932个光谱的单个球状星团的最大样本。我们得出平均径向速度vrad = 17.84 ± 0.07 km s−1，平均金属丰度[Fe/H] = −2.120 ± 0.002，后者似乎随红巨星分支（RGB）上恒星的温度而变化。我们确定Teff和[Fe/H]从光谱，和log g从HST光度法。这是第一张非常全面的球状星团赫兹-罗素图（HRD），基于对数千颗恒星光谱的分析，从主序到RGB的尖端。此外，还发现了两个有趣的天体;一个是后AGB星星，另一个可能是毫秒脉冲星伴星。
Aims. We demonstrate the high multiplex advantage of crowded field 3D spectroscopy with the new integral field spectrograph MUSE by means of a spectroscopic analysis of more than 12 000 individual stars in the globular cluster NGC 6397. Methods. The stars are deblended with a point spread function fitting technique, using a photometric reference catalogue from HST as prior, including relative positions and brightnesses. This catalogue is also used for a first analysis of the extracted spectra, followed by an automatic in-depth analysis via a full-spectrum fitting method based on a large grid of PHOENIX spectra. Results. We analysed the largest sample so far available for a single globular cluster of 18 932 spectra from 12 307 stars in NGC 6397. We derived a mean radial velocity of vrad = 17.84 ± 0.07 km s−1 and a mean metallicity of [Fe/H] = −2.120 ± 0.002, with the latter seemingly varying with temperature for stars on the red giant branch (RGB). We determine Teff and [Fe/H] from the spectra, and log g from HST photometry. This is the first very comprehensive Hertzsprung-Russell diagram (HRD) for a globular cluster based on the analysis of several thousands of stellar spectra, ranging from the main sequence to the tip of the RGB. Furthermore, two interesting objects were identified; one is a post-AGB star and the other is a possible millisecond-pulsar companion.
M 星大气速度的 3D 模拟及其对分子 FeH 谱线的影响
影响因子：
6.5
作者：
Reiners;Ludwig
通讯作者：
Ludwig