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Aufsatz
Influence of the interaction potential on simulated sputtering and reflection data
(1992)
The TRIM.SP program which is based on the binary collision approximation was changed to handle not only repulsive interaction potentials, but also potentials with an attractive part. Sputtering yields, average depth and reflection coefficients calculated with four different potentials are compared. Three purely repulsive potentials (Meliere, Kr-C and ZBL) are used and an ab initio pair potential, which is especially calculated for silicon bombardment by silicon. The general trends in the calculated results are similar ...
Aufsatz
Fluorescence studies on the 3d-ionization threshold range in krypton
(1994)
Krypton atoms were excited by photons in the energy range from the threshold for photoionization of the 3d-electrons up to 120 eV. and the fluorescence radiation in the spectral range from 780 to 965 A was observed and analyzed. Cross sections for the population of excited states in KrIII with at least one 4s-hole resulting from an Auger transition as the first decay step and for KrII satellites were determined. The energy dependence of the 3d-ionization cross section in the 3d{_5/2}- and the 3d{_3/2}-threshold range ...
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State-selective study of the direct double photoionization of the Ne valence shell
(1993)
Cross sections for double photoionization of the Ne L shell into the 2s2p{^5 3}P^0} and ^1P^0 and the 2s^02p^6 ^1S^e states were measured for energies from threshold up to 150 eV, using photon induced fluorescence spectroscopy. Both 2s2p^5 channels were observed with comparable magnitude in contradiction to a propensity rule based on the Wannier-Peterkop-Rau theory. A comparison of the summed ^3P^0 and ^1P^0 cross sections with MBPT calculations results in a deviation of 50%.
Aufsatz
Absolute Kr 4s-electron photoionization cross sections between 30 and 90 eV measured by photon-induced fluorescence spectroscopy (PIFS)
(1994)
Absolute Kr 4s-electron photoionization cross sections as a function of the exciting-photon energy between 30 and 90 eV were measured by photon-induced fluorescence spectroscopy (PIFS). The measurements were compared with available experimental data and theoretical calculations.
Aufsatz
Threshold scan of the Ne 2s-electron photoionization cross edition
(1990)
The photoionization of the Ne 2s-electrons was studied from threshold to 1 eV above threshold. The technique of photon-induced fluorescence spectroscopy was applied. Pronounced structures were observed resulting from autoionization of doubly excited atomic states. A threshold cross section of 0.17 Mb was determined.
Aufsatz
Interchannel interactions and relaxation in the 2p auger spectra of Mg-like ions
(1992)
Relativistic Auger rates for the 2p spectra of Mg-like ions have been calculated in the atomic range 13 < Z < 36. We used the multiconfiguration Dirac-Fock method but beyond a simple frozen-orbital approach we include also relaxation for the bound electrons and the interchannel interaction between the continuum states. Both effects may alter the individual transition rates remarkably. This is analysed for a few selected states within the isoelectronic sequence. Weak transitions within the 2p spectra can be changed ...
Aufsatz
Calculation of the hyperfine structure transition energy and lifetime in the one-electron Bi^82+ ion
(1993)
We calculate the energy and lifetime of the ground state hyperfine structure transition in one-electron Bi^82+ . The influence of various distributions of the magnetic moment and the electric charge in the nucleus ^209_83 Bi on energy and lifetime is studied.
Aufsatz
Formen der Öffnung im Fremdsprachenunterricht: ein Gedankenaustausch
(1998)
Formen der . Öffnung" - was ist damit eigentlich gemeint? Woher kommt das Interesse an diesem Thema? Was spricht für Öffnung, was spricht dagegen? Welche Vorteile darf man von Öffnung erwarten, welche neuen Probleme gilt es zu lösen? Und welche Konsequenzen ergeben sich, wenn man erst einmal mit Öffnung beginnt? Für uns besteht eine Konsequenz darin, nicht nur das Konzept von Unterricht, sondern auch das Sprechen darüber zu verändern. Und so haben wir zwei engagierten Kolleginnen, Frau Ferrante und Frau Rosendahl-Schnelle, ...
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Three-electron radiative transitions
(1993)
A new type of many-electron radiative transitions involving three electrons is predicted. The results of their investigation by many-body perturbation theory are presented. New spectral lines observed in the wavelength range of 37.5 to 54.0 nm by means of photon-induced fluorescence spectroscopy (PIFS) following the excitation of the Kr I 3d{^-1}np resonances are reported and compared with the predictions.
Aufsatz
[Editorial]
(1998)