相关论文: Hyperfine induced transitions probabilities from $…
Hyperfine induced $2s2p~^3P_0 \rightarrow 2s^2~^1S_0$ transition rates in an external magnetic field for Be-like $^{47}$Ti were calculated based on the multiconfiguration Dirac-Fock method. It was found that the transition probability is…
Hyperfine induced $1s2s ^1S_0 \to 1s^2 ^1S_0$ M1 transition probabilities of He-like ions have been calculated from relativistic configuration interaction wavefunctions including the frequency independent Breit interaction and QED effects.…
The hyperfine induced $2s2p ^3P_0, ^3P_2 \to 2s^2 ^1S_0$ E1 transition probabilities of Be-like ions were calculated using grasp2K based on multi-configuration Dirac-Fock method and HFST packages. It was found that the hyperfine quenching…
Iridium ions near $4f$-$5s$ level crossings are the leading candidates for a new type of atomic clocks with a high projected accuracy and a very high sensitivity to the temporal variation of the fine structure constant $\alpha$. To identify…
Energies, wavelengths, transition probabilities, and oscillator strengths have been calculated for the 4s24p2-4s4p3, 4s24p2-4s24p4d and 4s4p3-4p4 allowed transitions in heavy Ge-like ions with Z=59-63. The fully relativistic…
We study the theoretical foundations for the pressure shifts in high-precision atomic beam spectrosopy of hydrogen, with a particular emphasis on transitions involving higher excited P states. In particular, the long-range interaction of an…
The ground state hyperfine splitting values and the transition probabilities between the hyperfine structure components of high Z lithiumlike ions are calculated in the range $Z=49-83$. The relativistic, nuclear, QED and interelectronic…
We calculated the magnetic dipole and the electric quadrupole hyperfine interaction constants of 3s3p $^{3,1}P^o_1$ states and the isotope shift, including mass and field shift, factors for transitions from these two states to the ground…
Large-scale $\textit{ab initio}$ calculations of the electric field gradient, which constitutes the electronic contribution to the electric quadrupole hyperfine constant $B$, were performed for the $5s^25p6s$ $^{1,3}\!P^{\rm o}_1$ excited…
We report theoretical results for magnetic field induced $2p^53s^3P_{0,2} - 2p^6^1S_0$ E1 transitions in Ne-like ions with zero nuclear spin (I=0) between Mg III and Zn XXI as well as in Ne I. We demonstrate that it is important to include…
The radiative transitions between the $4d^{10}5p^2(^3P_{0,1,2})nl$ and {$4d^{10}5s5p({}^3P_1^o)nl$ autoionizing} states of an indium atom that represent dielectronic satellites of the $4d^{10}5p^2 {}^3P_0 \to 4d^{10}5s5p {}^3P_1$ ($\lambda…
The status of experimental measurements and theoretical calculations of the hyperfine induced 2s2p 3P0 -> 2s2 1S0 transition rate in Be-like ions is reviewed. Possible reasons, such as external electromagnetic fields and competing E1M1…
A measurement of the hyperfine coefficients and isotope shifts for the Dy I 421.291 nm transition [$4f^{10}6s^2 (J=8)\to4f^{10}6s6p (J=9)$] using atomic beam laser-induced fluorescence spectroscopy is presented. A King Plot analysis is…
Hyperfine-induced electric dipole contributions may significantly increase probabilities of otherwise very weak electric octupole and magnetic quadrupole atomic clock transitions (e.g. transitions between $s$ and $f$ electron orbitals).…
In this paper, we used the multiconfiguration Dirac-Fock method to compute with high precision the influence of the hyperfine interaction on the $[Ar]3d^{10} 4s4p ^3P_0$ level lifetime in Zn-like ions for stable and some quasi-stable…
We investigate the quantum interference induced shifts between energetically close states in highly charged ions, with the energy structure being observed by laser spectroscopy. In this work, we focus on hyperfine states of lithiumlike…
Two anomalously weak transitions within the $2 ^3{\rm S}_1~-~3 ^3{\rm P}_J$ manifolds in $^3$He have been identified. Their transition strengths are measured to be 1,000 times weaker than that of the strongest transition in the same group.…
We report measurements and theoretical calculations of the fine-structure splittings in all three $1s2s\,^3\!S_1\rightarrow\,1s2p\,^3\!P_{0,1,2}$ transitions in the heliumlike systems of the isotopes $^{12,13,14}$C. The metastable triplet…
We characterize the Europium (Eu$^{3+}$) hyperfine interaction of the excited state ($^5$D$_0$) and determine its effective spin Hamiltonian parameters for the Zeeman and quadrupole tensors. An optical free induction decay method is used to…
Collisions of metastable antiprotonic helium atoms with atoms of the medium induce, among other processes, transitions between hyperfine structure (HFS) states, as well as shifts and broadening of microwave M1 spectral lines. In order to…