We report new branching fraction measurements for 199 UV and optical transitions of Hf ii. These transitions range in wavelength (wavenumber) from 2068 to 6584 Å (48,322–15,183 cm⁻¹) and originate in 17 odd-parity upper levels ranging in energy from 38,578 to 53,227 cm⁻¹. The branching fractions are combined with radiative lifetimes reported in an earlier study to produce a set of transition probabilities and log(gf) values with accuracy ranging from 5% to 25%. Comparison is made to transition probabilities from the literature where such data exist. We use these new transition probabilities to derive improved Hf abundances in two metal-poor stars. HD 196944 is enhanced in s-process elements, and we derive log ε (Hf) = −0.72 0.03 (σ = 0.09) from 12 Hf ii lines. HD 222925 is enhanced in r-process elements, and we derive log ε (Hf) = 0.32 0.03 (σ = 0.11) from 20 Hf ii lines. These measurements greatly expand the number of potentially useful Hf ii lines for analysis in UV and optical spectra.

我们报告了 Hf ii 的199 UV 和光学跃迁的新分支分数测量值。这些跃迁的波长（波数）范围从 2068 到 6584 Å（48,322–15,183 cm ^-1），并且起源于能量范围从 38,578 到 53,227 cm ^{-1 的}17 个奇校验上能级。分支分数与早期研究中报告的辐射寿命相结合，以产生一组跃迁概率和 log( gf ) 值，精度范围为 5% 到 25%。对存在此类数据的文献中的转移概率进行比较。我们使用这些新的跃迁概率来推导出两颗贫金属恒星中改进的 Hf 丰度。HD 196944 在 s-process 元素中得到增强，我们推导出 log ε(Hf) = -0.72 0.03 ( σ = 0.09) 来自 12 个 Hf ii线。HD 222925 在 r-process 元素中得到增强，我们从 20 个 Hf ii线推导出 log ε (Hf) = 0.32 0.03 ( σ = 0.11) 。这些测量极大地扩展了在紫外光谱和光谱分析中可能有用的 Hf ii谱线的数量。