We report first configuration interaction calculations of hyperfine constants A_\parallel and the effective electric field W_d acting on the electric dipole moment of the electron, in two excited electronic states of ^{207}PbO. The obtained hyperfine constants, A_\parallel = -3826 MHz for the a(1) state and A_\parallel = 4887 MHz for the B(1) state, are in very good agreement with the experimental data, -4113 MHz and 5000 \pm 200 MHz, respectively. We find W_d = -(6.1 ^{+1.8}_{-0.6}) 10^{24} Hz/(e cm) for a(1), and W_d = (8.0 \pm 1.6) 10^{24} Hz/(e cm) for B(1). The obtained values are analyzed and compared to recent relativistic coupled cluster results and a semiempirical estimate of W_d for the a(1) state.
Experiments with paramagnetic ground or metastable excited states of molecules (ThO, HfF$^+$, YbF, YbOH, BaF, PbO, etc.) provide strong constraints on electron electric dipole moment (EDM) and coupling constant $C_{SP}$ of contact semileptonic interaction. We compute new contributions to $C_{SP}$ arising from the nucleon EDMs due to combined electric and magnetic electron-nucleon interaction. This allows us to improve limits from the experiments with paramagnetic molecules on the $CP$-violating parameters, such as the proton EDM, $|d_p|< 1.1\times 10^{-23} e\cdot $cm, the QCD vacuum angle, $|\…
CP violation effects produced by the nuclear magnetic quadrupole moment (MQM), electron electric dipole moment (EDM) and scalar$-$pseudoscalar nucleus$-$electron neutral current (SP) interaction in $^{177}$Hf$^{19}$F$^+$ and $^{179}$Hf$^{19}$F$^+$ are calculated. The role of the hyperfine interaction is investigated. It is shown that the MQM shift can be distinguished from the electron EDM and SP ones due to the implicit dependence of MQM shift on the hyperfine sublevel. The MQM effect is expressed in terms of the proton (EDM), QCD vacuum angle $θ$ and quark chromo-EDMs.
We demonstrate a spin-precession method to observe and analyze multi-level coherence between all hyperfine levels in the $X ^2Σ^+,N=0$ ground state of barium monofluoride ($^{138}$Ba$^{19}$F). The signal is sensitive to the state-preparation Rabi frequency and external electric and magnetic fields applied in searches for a permanent electric dipole moment (EDM). In the obtained interference spectrum, the electric field and Rabi frequency become observable simultaneously with the EDM. This method reduces systematic biases and the number of auxiliary measurements for such precision measurements.
TaN molecule as a candidate to search for New physics
结果表明，TaN分子是寻找T，P-破坏的核磁四极矩（MQM）的最佳候选者，它也有希望寻找其他T，P-奇效应。本文报道了Ta核MQM、电子电偶极矩（EDM）、标量$-$和赝标量核$-$电子相互作用产生的T，P奇效应，以及分子轴超精细结构常数和偶极矩的耦合簇计算结果。用T，P奇核力强度常数、质子和中子EDM、QCD参数$θ$和夸克色模EDM对$^{181}$ Ta MQM进行了核计算，以表达T，P奇效应.
Permanent electric dipole moments (EDMs) of fundamental particles such as the electron are signatures of parity and time-reversal violation due to physics beyond the standard model. EDM measurements probe new physics at energy scales well beyond the reach of present-day colliders. Recent advances in assembling molecules from ultracold atoms have opened up new opportunities for improving the reach of EDM experiments. But better measurement techniques, that are not limited by the magnetic field sensitivity of such molecules, are necessary before these opportunities can be fully exploited. We pre…
We perform model-independent analyses extracting limits for the electric dipole moment of the electron and the P,T-odd scalar-pseudoscalar (S-PS) nucleon-electron coupling from the most recent measurements with atoms and molecules. The analysis using paramagnetic systems, only, is improved substantially by the inclusion of the recent measurement on HfF+ ions, but complicated by the fact that the corresponding constraints are largely aligned, owing to a general relation between the coefficients for the two contributions. Since this same relation does not hold in diamagnetic systems, it is possi…
We perform calculations of the CP-violating atomic and molecular electric dipole moments (EDM) induced by the interaction of the nuclear Schiff moments with electrons. EDM of atoms Eu, Dy, Gd, Ac, Th, Pa, U, Np and Pu are of special interest since they have isotopes with strongly enhanced nuclear Schiff moments caused by the octupole nuclear deformation or soft octupole vibration mode. These atoms have open 4f or 5f shells making the calculations complicated. We use our special version of the configuration interaction method combined with the many-body perturbation theory method adopted for op…
The CP-violating interaction of the nuclear magnetic quadrupole moment (MQM) of the $^{175}$Lu nucleus with electrons in the molecular cation LuOH$^+$ is studied. The resulting effect is expressed in terms of CP-odd parameters, such as quantum chromodynamics angle $\barθ$, quark electric dipole moment (EDM) and chromo-EDM. For this we have performed a calculation of the nuclear MQM as well as the molecular constant that characterises the interaction of this MQM of $^{175}$Lu with electrons. Additionally, we predict the hyperfine structure constants for the ground electronic state of LuOH$^+$. …
The relativistic coupled-cluster (RCC) method is a powerful many-body method, particularly in the evaluation of electronic wave functions of heavy atoms and molecules, and can be used to calculate various atomic and molecular properties. One such atomic property is the enhancement factor (R) of the atomic electric dipole moment (EDM) due to an electron EDM needed in electron EDM searches. The EDM of the electron is a sensitive probe of CP-violation, and its search could provide insights into new physics beyond the Standard Model, as well as open questions in cosmology. Electron EDM searches us…
The LuOH$^+$ cation is a promising system to search for manifestations of time reversal and spatial parity violation effects. Such effects in LuOH$^+$ induced by the electron electric dipole moment $e$EDM and the scalar-pseudoscalar interaction of the nucleus with electrons, characterized by $k_s$ constant, in LuOH$^+$ are studied. The enhancement factors, polarization in the external electric field, hyperfine interaction, rovibrational structure are calculated. The study is required for the experiment preparation and extraction of the eEDM and ks values from experimental data.
Probing $P,T$-Symmetry Violation with Optically Trapped Asymmetric Top Molecules
California Institute of Technology（加州理工学院）；Harvard/MIT Center for Ultracold Atoms（哈佛/麻省理工超冷原子中心）；Massachusetts Institute of Technology（麻省理工学院）；Harvard University（哈佛大学）；University of Groningen（格罗宁根大学）；Nikhef, National Institute for Subatomic Physics（荷兰国家亚原子物理研究所）；Comenius University（科梅尼斯大学）；Instituto de Modelado e Innovación Tecnológica (IMIT), CONICET–Universidad Nacional del Nordeste（国家科学技术研究委员会-东北国立大学建模与技术创新研究所）
