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Aufsatz
Zur Vakuumpolarisation in Myonenatomen
(1969)
The various approximations of vacuum polarization potential and the higher order
corrections up to \alpha^3 are reviewed and quantitatively dicussed. The quadrupol part of the vacuum polarization is established. It leads rather straight forward to a small
contribution of vacuum polarization to nuclear polarization. These effects are quantitatively investigated.
Aufsatz
Beam-foil-excited auger transitions in neon
(1975)
Energy spectra of electrons ejected from collisions between a carbon foil and Ne
projectiles with energies between 1.4 and 20 MeV have been measured. Continuous and
discrete electron energy distributions are observed. Auger transitions of foil-excited Ne have been studied. Using relativistic Dirac-Fock multiconfiguration calculations, most of the measured Auger transitions have been identified.
Aufsatz
Electronic structure of UF_5
(1979)
Non-relativistic and relativistic self-consistent Hartree- Fock-Slater and Dirac-Slater models have been used to calculate one-electron energy levels and ionization energies for UF_5. The calculations were performed in an assumed structure of C_4v symmetry with the uranium atom at the center of mass of the molecule. The spacing and level ordering are compared
with earlier results obtained with the MS X\alpha method using the muffin-tin approximation. Connections with the multiphoton isotope separation scheme of UF_6 ...
Aufsatz
The problem of noncharacteristic quasimolecular X-rays in heavy ion collision
(1976)
Quasi-molecular X-rays observed in heavy ion collisions are interpreted within a relativistic calculation of correlation diagrams using the Dirac-Slater model. A semiquantitative description of noncharacteristic M X rays is given for the system Au-I.
Aufsatz
Hyperfine structure and isotopic shift of the n^2 P_J levels (n = 7-10) of ^203,205 TI measured by Doppler-free two-photon spectroscopy
(1988)
Using Doppler-free two-photon absorption spectroscopy, we have measured hyperfine splitting constants as well as isotopic level shifts of the 6s^2 np ^2 P_l/2,3/2 states in (n=7-10) in ^203 TI and ^205 TI.
Calculations for hyperfine constants and electron density at the nucleus have been performed by the Dirac-Fock method. The experimental results are compared with these calculations as well as with
the predictions of the semiempirical theory.
Aufsatz
Ground state correlation energy of the Be-sequence for Z = 4-20 in MCDF approximation
(1989)
The ground state (J = 0) electronic correlation energy of the 4-electron Be-sequence is calculated in the Multi-Configuration Dirac-Fock approximation for Z = 4-20. The 4 electrons were distributed over the configurations arising from the 1s, 2s, 2p, 3s, 3p and 3d orbitals. Theoretical values obtained here are in good agreement with experimental correlation energies.
Aufsatz
Interpretation of the anisotropy of M MO radiation in slow I on Au collisions
(1979)
A comparison between experimental and calculated spectral shape and energy dependence of the M MO x-ray anisotropy in heavy-ion collisions of I on Au is presented. The calculation is performed within the kinematic-dipole model of anisotropy using MO x-rays determined from SCF relativistic correlation diagrams.
Aufsatz
Calculation of isomer shift in Mössbauer spectroscopy
(1972)
The approximations normally used in the calculation of the isomer shift are compared with the exact expressions using Dirac-Slater orbitals and a three-parameter Fermi-type nuclear charge distribution. The nonuniformity of the electronic density over the nuclear volume affects the results. Different choices of the nuclear surface thickness t and the radius c in the protonic
density P_N (\gamma) also affects the isomer shift differently even though the values are chosen to yield a given value of \delta <r^2>. The ...
Aufsatz
Self-energy corrections in heavy muonic atoms
(1978)
Self-energy corrections for ls_1/2 levels of heavy muonic atoms are calculated to all orders in the external field using numerical techniques to evaluate the bound-muon propagator. The resulting values of the selfenergy are about 10% larger than previous estimates.