标题： Gd 转移概率和丰度 显示英文标题

标题： Gd Transition Probabilities and Abundances

摘要： 辐射寿命的测量精度为±5%，用于测量49个偶宇称和14个奇宇称能级的Gd II。这些寿命与使用傅里叶变换光谱法测量的分支分数相结合，以确定Gd II的611条线的跃迁概率。这项工作是迄今为止对Gd II跃迁概率的最大规模实验室研究，并且是首次使用高性能傅里叶变换光谱仪的研究。这改进的数据集已被用来确定新的太阳光球层Gd丰度，log epsilon = 1.11 ± 0.03。还推导出了富含r过程的贫金属巨星CS 22892-052、BD+17 3248和HD 115444的修订Gd丰度。得到的Gd/Eu丰度比与太阳系r过程比值非常一致。我们利用日益准确的恒星丰度测定结果，这部分主要来自更精确的实验室原子数据，直接预测了太阳系r过程元素Gd、Sm、Ho和Nd的丰度。我们对恒星数据的分析表明，对于Gd、Sm和Ho元素，r过程贡献和太阳系总值的推荐值略高，这与光球层测定结果一致。 显示英文摘要

摘要： Radiative lifetimes, accurate to +/- 5%, have been measured for 49 even-parity and 14 odd-parity levels of Gd II using laser-induced fluorescence. The lifetimes are combined with branching fractions measured using Fourier transform spectrometry to determine transition probabilities for 611 lines of Gd II. This work is the largest-scale laboratory study to date of Gd II transition probabilities and the first using a high performance Fourier transform spectrometer. This improved data set has been used to determine a new solar photospheric Gd abundance, log epsilon = 1.11 +/- 0.03. Revised Gd abundances have also been derived for the r-process-rich metal-poor giant stars CS 22892-052, BD+17 3248, and HD 115444. The resulting Gd/Eu abundance ratios are in very good agreement with the solar-system r-process ratio. We have employed the increasingly accurate stellar abundance determinations, resulting in large part from the more precise laboratory atomic data, to predict directly the Solar System r-process elemental abundances for Gd, Sm, Ho and Nd. Our analysis of the stellar data suggests slightly higher recommended values for the r-process contribution and total Solar System values, consistent with the photospheric determinations, for the elements for Gd, Sm, and Ho.