A short period undulator for MAX

Final ionic state-configuration interaction (FISCI) between bound 4s −1 4p −1 np and 4s 2 4p −3 mdnp final states in the Auger decay of resonantly excited Kr 3d −1 np states has been studied by synchrotron-radiation-excited electron spectroscopy utilizing the Auger resonant Raman effect. It is found that the effects of FISCI are essentially the same as in the corresponding normal Auger spectra. Especially in the 3d −1 5p → 4s −1 4p −1 5p spectra the role of FISCI is to distribute the intensity from the 4s −1 4p −1 5p 'diagram' states to the 4s 2 4p −3 4d5p 'satellite' states without remarkably affecting the branching ratio of the 'diagram' lines. Furthermore, the experimental shake probabilities are not affected by FISCI.

Section: Methodsmentioning

confidence: 99%

High resolution study of correlation satellites in the - resonant Auger spectra of Kr

Mursu¹,

Jauhiainen²,

Aksela³

et al. 1998

“…A detailed description of the beamline has been published elsewhere [12]. Shortly, the beamline uses synchrotron radiation from an undulator [13] in the photon energy range of 60-600 eV and it has a modified SX-700 plane grating monochromator [14]. The beamline contains a permanent differential pumping and refocusing section designed to effectively isolate the high-pressure gas experiments from the ultrahigh vacuum of the monochromator.…”

Section: Methodsmentioning

confidence: 99%

Cascade versus shake-off satellite Auger transitions in the Ar L - MM spectrum

Kylli

Aksela

Sairanen

et al. 1997

The L 2,3 -MM Auger spectra of argon have been created bombarding the sample gas by either 2 keV electrons or 398 eV and 315 eV photons. The 2p photoionization created by 315 eV photons may be accompanied by a simultaneous excitation of another electron to an unoccupied orbital or to the continuum. High-energy electrons and 398 eV photons can ionize the 2s subshell which may lead to the L 1 -L 2,3 [M]-MM[M] satellite Auger transitions. Semiempirical kinetic energies of the L 2,3 [M]-MM[M] satellite Auger transitions have been estimated with the aid of MCDF calculations, the 2p shake-up spectrum, the L 1 -L 2,3 M Coster-Kronig spectrum and the final-state binding energies from optical data. Intensities of the transitions have also been calculated by using a MCDF code. A comparison of the semi-empirical and observed energies with the calculated and observed intensities has allowed us to assign a manifold of the satellite peaks in the measured spectrum. We have also investigated the changes in intensity distribution of satellites in passing from cascade satellites to those created via shake-off processes accompanying photoionization.

“…A detailed description of the beamline has been published elsewhere [18]. Briefly, the beamline uses synchrotron radiation from an undulator [19] in the photon energy range of 60-600 eV and it has a modified SX-700 plane grating monochromator [20] with a plane elliptical focusing mirror. The beamline contains a permanent differential pumping section designed to isolate effectively the high pressure gas experiments from the ultra high vacuum of the monochromator.…”

Section: Methodsmentioning

confidence: 99%

Correlation effects in the - MM Auger transitions of Ar

Pulkkinen

Aksela

Sairanen

et al. 1996

L 2,3 -MM Auger spectra of argon have been measured with very high resolution using excitation by monochromatic synchrotron radiation. The photon energy was selected slightly above the 2p ionization threshold for creation of the single 2p core hole state only. The Auger spectra are thus free from any satellite lines originating from two-hole initial states and therefore well suited to study the configuration interaction in the final ionic state of the decay. Electron correlation is investigated by calculating the energies and intensities of the transitions using the multiconfiguration Dirac-Fock method and by comparing them with the experimental results.