论文标题
少数电子分子中的精度测量值：亚稳态$ \ MATHBF {^4} $ HE $ \ MATHBF {_2} $的电离能量和$ \ Mathbf {^4} $ he He $ \ Mathbf {^4} $ \ MathBf {^4
Precision Measurements in Few-Electron Molecules: The Ionization Energy of Metastable $\mathbf{^4}$He$\mathbf{_2}$ and the First Rotational Interval of $\mathbf{^4}$He$\mathbf{{_2}^+}$
论文作者
论文摘要
分子氦代表用于测试$ \ textit {ab intio} $计算的基准系统。我们报告了$ a \，^3σ_U^+$ He $ _2 $状态的绝热电离能量的确定，对应于$ a \，^3σ_U^+$（$ v'= 0 $，$ n'= 0 $，$ n'= 1 $）He $ _2 $ and $ _2 $ and $ x^+^$^$^$^$^， $ n^+= 1 $）He $ {_ 2}^+$的状态，以及He $ {_ 2}^+$的最低旋转间隔。这些测量值依赖于在反向传播激光梁的设置中使用频率击败的连续波UV辐射的频率 - bomb校准的连续紫外线辐射的刺激。使用多通道量子缺陷理论将观察到的Rydberg状态推算为其串联限制。 He $ _2 $（$ a \，^3σ_U^+$）的电离能和He $ {_ 2}^+$的最低旋转间隔（$ x^+\，^2σ_U^+$）是34301.207002（23）$ 70.937589（23）$ \ pm 0.000060 _ {\ mathrm {sys}} $ cm $^{ - 1} $。
Molecular helium represents a benchmark system for testing $\textit{ab initio}$ calculations on few-electron molecules. We report on the determination of the adiabatic ionization energy of the $a\,^3Σ_u^+$ state of He$_2$, corresponding to the energy interval between the $a\,^3Σ_u^+$ ($v''=0$, $N''=1$) state of He$_2$ and the $X^+\,^2Σ_u^+$ ($v^+=0$, $N^+=1$) state of He${_2}^+$, and of the lowest rotational interval of He${_2}^+$. These measurements rely on the excitation of metastable He$_2$ molecules to high Rydberg states using frequency-comb-calibrated continuous-wave UV radiation in a counter-propagating-laser-beam setup. The observed Rydberg states were extrapolated to their series limit using multichannel quantum-defect theory. The ionization energy of He$_2$ ($a\,^3Σ_u^+$) and the lowest rotational interval of He${_2}^+$ ($X^+\,^2Σ_u^+$) are 34301.207002(23)$\pm 0.000037_{\mathrm{sys}}$ cm$^{-1}$ and 70.937589(23)$\pm 0.000060_{\mathrm{sys}}$ cm$^{-1}$, respectively.
