387 research outputs found

### Calculation of Radiative Corrections to E1 matrix elements in the Neutral Alkalis

Radiative corrections to E1 matrix elements for ns-np transitions in the
alkali metal atoms lithium through francium are evaluated. They are found to be
small for the lighter alkalis but significantly larger for the heavier alkalis,
and in the case of cesium much larger than the experimental accuracy. The
relation of the matrix element calculation to a recent decay rate calculation
for hydrogenic ions is discussed, and application of the method to parity
nonconservation in cesium is described

### Relativistic corrections of m\alpha^6 order to the ro-vibrational spectrum of H_2^+ and HD^+ molecular ions

The major goal of the high-precision studies of ro-vibrational states in the
hydrogen molecular ions is to provide an alternative way for improving the
electron-to-proton mass ratio, or the atomic mass of electron. By now the
complete set of relativistic and radiative corrections have been obtained for a
wide range of ro-vibrational states of H_2^+ and HD^+ up to order
R_\infty\alpha^4. In this work we complete calculations of various
contributions to the R_\infty\alpha^4 order by computing the relativistic
corrections to the binding energy of electron.Comment: 4 pages, 1 figur

### Hyperfine structure of S states in Li and Be^+

A large-scale configuration-interaction (CI) calculation is reported for the
hyperfine splitting of the 2^2S and 3^2S states of ^7Li and ^9Be^+. The CI
calculation based on the Dirac-Coulomb-Breit Hamiltonian is supplemented with a
separate treatment of the QED, nuclear-size, nuclear-magnetization
distribution, and recoil corrections. The nonrelativistic limit of the CI
results is in excellent agreement with variational calculations. The
theoretical values obtained for the hyperfine splitting are complete to the
relative order of \alpha^2 and improve upon results of previous studies.Comment: 4 pages, 2 table

### Vacuum polarization calculations for hydrogenlike and alkalilike ions

Complete vacuum polarization calculations incorporating finite nuclear size
are presented for hydrogenic ions with principal quantum numbers n=1-5.
Lithiumlike, sodiumlike, and copperlike ions are also treated starting with
Kohn-Sham potentials, and including first-order screening corrections. In both
cases dominant Uehling terms are calculated with high accuracy, and smaller
Wichmann- Kroll terms are obtained using numerical electron Green's functions.Comment: 23 pages, 1 figur

### Self-energy values for P states in hydrogen and low-Z hydrogenlike ions

We describe a nonperturbative (in Zalpha) numerical evaluation of the
one-photon electron self energy for 3P_{1/2}, 3P_{3/2}, 4P_{1/2} and 4P_{3/2}
states in hydrogenlike atomic systems with charge numbers Z=1 to 5. The
numerical results are found to be in agreement with known terms in the
expansion of the self energy in powers of Zalpha and lead to improved
theoretical predictions for the self-energy shift of these states.Comment: 3 pages, RevTe

### Radiative Corrections to One-Photon Decays of Hydrogenic Ions

Radiative corrections to the decay rate of n=2 states of hydrogenic ions are
calculated. The transitions considered are the M1 decay of the 2s state to the
ground state and the E1(M2) decays of the $2p_{1/2}$ and $2p_{3/2}$ states to
the ground state. The radiative corrections start in order $\alpha (Z
\alpha)^2$, but the method used sums all orders of $Z\alpha$. The leading
$\alpha (Z\alpha)^2$ correction for the E1 decays is calculated and compared
with the exact result. The extension of the calculational method to parity
nonconserving transitions in neutral atoms is discussed.Comment: 22 pages, 2 figure

- â€¦