We measure isotope shifts for five Yb$^+$ isotopes with zero nuclear spin on two narrow optical quadrupole transitions ${}^2S_{1/2} \rightarrow {}^2D_{3/2}$, ${}^2S_{1/2} \rightarrow {}^2D_{5/2}$ with an accuracy of $\sim 300$ Hz. The corresponding King plot shows a $3 \times 10^{-7}$ deviation from linearity at the 3 $σ$ uncertainty level. Such a nonlinearity can indicate physics beyond the Standard Model (SM) in the form of a new bosonic force carrier, or arise from higher-order nuclear effects within the SM. We identify the quadratic field shift as a possible contributor to the nonlinearity at the observed scale, and show how the nonlinearity pattern can be used in future, more accurate measurements to separate a new-boson signal from nuclear effects.
Precision Isotope-Shift Measurement of the ${}^1S_0 \leftrightarrow {}^3P_2$ Transition and a Multi-Transition King-Plot Consistency Test
Kyoto University（京都大学）；HIKARI-COOL Kyoto（HIKARI-COOL 京都）；The Hakubi Center for Advanced Research, Kyoto University（京都大学博雅研究高级研究中心）；ELTE, Eötvös Loránd University（罗兰大学）；High Energy Accelerator Research Organization (KEK)（高能加速器研究机构）；The University of Osaka（大阪大学）
Magneto-optical trapping of bosonic and fermionic neon isotopes and their mixtures: isotope shift of the ^3P_2 to ^3D_3 transition and hyperfine constants of the ^3D_3 state of Ne-21
Improved isotope-shift-based bounds on bosons beyond the Standard Model through measurements of the $^2$D$_{3/2} - ^2$D$_{5/2}$ interval in Ca$^+$
我们进行高分辨率光谱的$3$ d $~^2$ D $_{3/2} - 3$ d $~^2$ D $_{5/2}$间隔在所有稳定的甚至同位素$^A$钙$^+$（A = 40，42，44，46和48）的准确度为$\sim$ 20 Hz使用直接频率梳拉曼光谱。结合这些数据与同位素位移测量的4s $~^2$ S $_{1/2} \leftrightarrow 3$ d $~^2$ D $_{5/2}$过渡，我们进行了一个国王图分析与前所未有的灵敏度耦合电子和中子之间的玻色子超出标准模型。此外，我们估计的灵敏度，这样的玻色子从等效的光谱在Ba $^+$和Yb $^+$。最后，通过与Knollmann等人（2019）的最新数据相结合，数据产生了4s $~^2$ S $_{1/2} \leftrightarrow 3$ d $~^2$ D $_{3/2}$跃迁的同位素位移为10 ppm。
We demonstrate that the isotope shift in isotopomers of diatomic molecules, where the nucleus of one of its constituent atoms is replaced by another isotope, can be expressed as the sum of a field shift and a mass shift, similar to the atomic case. We show that a linear relation holds between atomic and molecular isotopes shifts, thus extending the King-plot analysis to molecular isotope shifts. Optical isotope shifts in YbF and ZrO and infrared isotope shifts in SnH are analyzed with a molecular King-plot approach, utilizing Yb$^{+}$ and Zr$^{+}$ ionic isotope shifts and charge radii of Sn ob…
本文研究了中性钡谱线的同位素位移问题。本文首先研究了几种常见的跃迁（$6s^2~^1S_0-6s6p~^{1,3}P^o_1$和$6s^2~^1S_0-6p^2~^3P_0$）。核均方电荷半径的变化值推导出可用的实验同位素位移使用我们的从头计算电子因素。从这些品系获得的三个集合$\{ δ\langle r^2\rangle^{A,A'}\} $彼此一致。可用的核均方半径与我们用于$6s5d~^3D_{1,2} -6s6p~^{1}P^o_1$跃迁的电子因子的组合产生了与Dammalapati等人的激光光谱测量相冲突的同位素位移值（Eur. J. D 53，1（2009））。
Analytic Response Relativistic Coupled-Cluster Theory: The first application to indium isotope shifts
在基础研究和原子核结构研究中，对原子体系同位素位移的精确计算需求日益增加，在相对论耦合集团理论框架下，提出了一种计算原子场位移和质量位移因子的能量导数方法.这种方法允许确定原子算符的期望值，克服了现有原子物理学方法中存在的基本问题，即它满足Hellmann-Feynman定理，不涉及任何非终止级数，并且不需要选择任何微扰参数。作为一个概念的证明，已开发的解析响应相对论耦合集群理论已被应用于确定质量转移和场转移因子为不同的原子状态的铟。在246.8-nm（5 p $^2$ P $_{3/2}$ $\rightarrow$ 9 s $^2$ S $_{1/2}$）和246.0-nm（5 p $^2$ P $_{1/2}$ $\rightarrow$ 8 s $^2$ S $_{1/2}$）跃迁中进行了$^{104-127}$ In的高精度同位素位移测量，以检验我们的理论结果。理论值和测量值之间的一个很好的协议被发现，这是已知的具有挑战性的多电子原子。计算出的原子因子允许一个准确的测定核电荷半径的地面和异构态的$^{104-127}$在同位素，提供了同位素独立的比较的绝对电荷半径。
We measure isotope shifts for neutral Yb isotopes on an ultranarrow optical clock transition $^{1}\text{S}_{0}-^{3}\text{P}_{0}$ with an accuracy of a few Hz. The part-per-billion precise measurement was possible by loading the ultracold atoms into a three-dimensional magic-wavelength optical lattice and alternately interrogating the isotope pairs, thus minimizing the effects due to the optical lattice light-shift and inter-atomic interaction as well as the drifts of a clock laser frequency and a magnetic field. The determined isotope shifts, combined with one of the recently reported isotope-…
Isotope shifts of $^{223-226,228}$Ra$^{19}$F were measured for different vibrational levels in the electronic transition $A^{2}{}Π_{1/2}\leftarrow X^{2}{}Σ^{+}$. The observed isotope shifts demonstrate the particularly high sensitivity of radium monofluoride to nuclear size effects, offering a stringent test of models describing the electronic density within the radium nucleus. Ab initio quantum chemical calculations are in excellent agreement with experimental observations. These results highlight some of the unique opportunities that short-lived molecules could offer in nuclear structure and…
We present the theoretical calculations of the electronic isotope shift factors of the $5d^{7}6s^{2} \ ^{4}\!F_{9/2} \to (\mbox{odd},J= 9/2)$ line at 247.587 nm, that were recently used to extract nuclear mean square radii and nuclear deformations of iridium isotopes [Mukai $\textit{et al.}$ (2020)]. The fully relativistic multiconfiguration Dirac-Hartree-Fock method and the relativistic configuration interaction method were used to perform the atomic structure calculations. Additional properties such as the $\textit{sharing rule}$, Landé $g$ factors or $\textit{phase tracking}$ were employed …
