Influence of correlation effects on the magnetic dipole hyperfine interaction in the low-lying states of Ca 

Abstract

The relativistic coupled cluster theory is employed to calculate the hyperfine structure of the 2S 1/2, 2P 1/2, 2P 3/2, 2D 3/2 and 2D 5/2 states of singly ionized calcium. The importance of correlation effects is highlighted. Our results are compared with other theoretical calculations and experiments.

Measurement of the hyperfine structure of theS1∕2−D5∕2transition inBenhelm1, Kirchmair2, Rapol3 et al. 2007Phys. Rev. A341130View full textAdd to dashboardCite

“…The energies of the S 1/2 (F = 4, m F = ±4) levels used in our spectroscopic measurements are linearly shifted by hδ ± = ±(g S 1/2 1 2 + g ′ I I)µ B B. From earlier measurements and calculations of the isotope shift [21] and the hyperfine splitting of the S 1/2 [10] and the D 5/2 [11,22,23] states, the transition frequencies on the quadrupole transition in 43 Ca + are known to within 20 MHz with respect to the transition in 40 Ca + . This enabled us to unambiguously identify the lines observed in spectra of the S 1/2 ↔ D 5/2 transition.…”

Relativistic coupled-cluster studies of ionization potentials, lifetimes, and polarizabilities in singly ionized calcium

“…The RCC method which is equivalent to all order perturbation theory has been recently used to obtain precise results and account for the correlation effects in single valence systems [13,14,15]. Atomic wave functions for single valence systems can be expressed in the framework of RCC theory as…”

“…In these measurements, the knowledge of polarizabilities is necessary to estimate the black-body shift (BBS) and the Stark shift due to the external electromagnetic fields. In our recent works, we have reported the hyperfine structure constants and quadrupole moments in Ca + using the relativistic coupled-cluster (RCC) method [13,14,15]. The determination of electric dipole polarizabilities requires electric dipole (E1) matrix elements and excitation energies of all the allowed transitions.…”

Relativistic effective valence shell Hamiltonian method: Excitation and ionization energies of heavy metal atoms

“…33 The CC calculation 33 shows that higher order contributions are necessary for accurately describing the magnetic hyperfine matrix elements for the 3d 5/2 ͑ 2 D 5/2 ͒ state of Ca + . 33 The accuracy of the 6p 3/2 ͑ 2 P 3/2 ͒ state A value for Pb + strongly suggests that the inclusion of higher order correlation corrections is likewise necessary for an accurate determination of A when the core-polarization contribution is large and negative with respect to the DF value. The lifetime for the excited states of Sr + and Ba + are computed from the E1 transition probabilities, while the lifetime of the 6p ͑ 2 P 3/2 ͒ state of Pb + is estimated from the M1 and E2 transition probabilities.…”