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Title: Population of individual Ne 1s{sup -1}np Rydberg states measured across the 1s ionization threshold and the evolution of shake-up into shake-down

Abstract

New high-resolution experimental results on Ne 1s near-threshold photoionization with subsequent decay into a 2p{sup 4}({sup 1}D{sub 2})n{sup '}p or 2p{sup 4}({sup 1}D{sub 2}){epsilon}{sup '}p state are presented. The population of Rydberg states up to n{sup '}=12 is determined as a function of excess energy. These data allow one to track in detail the transition from resonant Auger decay going along with shake-up of the spectator electron to shake-down and photoionization with recapture of the photoelectron. Results are in good agreement with a time-dependent quantum mechanical theory of Auger decay in the presence of a slow photoelectron.

Authors:
 [1];  [2];  [3]; ;  [1];  [4];  [1];  [2];  [5]
  1. Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan)
  2. (Germany)
  3. Japan Synchrotron Radiation Research Institute, Sayo-gun, Hyogo 679-5198 (Japan)
  4. Fock Institute of Physics, State University of Sankt-Petersburg, 198504 Saint-Petersburg (Russian Federation)
  5. (Russian Federation)
Publication Date:
OSTI Identifier:
20974580
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.73.022709; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; AUGER EFFECT; DECAY; ELECTRONIC STRUCTURE; ELECTRONS; NEON; PHOTOIONIZATION; PHOTON-ATOM COLLISIONS; QUANTUM MECHANICS; RYDBERG STATES; TIME DEPENDENCE

Citation Formats

Hergenhahn, U., Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, 85748 Garching, De Fanis, A., Pruemper, G., Ueda, K., Kazansky, A. K., Kabachnik, N. M., Fakultaet fuer Physik, Universitaet Bielefeld, 33615 Bielefeld, and Institute of Nuclear Physics, Moscow State University, Moscow 119992. Population of individual Ne 1s{sup -1}np Rydberg states measured across the 1s ionization threshold and the evolution of shake-up into shake-down. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.022709.
Hergenhahn, U., Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, 85748 Garching, De Fanis, A., Pruemper, G., Ueda, K., Kazansky, A. K., Kabachnik, N. M., Fakultaet fuer Physik, Universitaet Bielefeld, 33615 Bielefeld, & Institute of Nuclear Physics, Moscow State University, Moscow 119992. Population of individual Ne 1s{sup -1}np Rydberg states measured across the 1s ionization threshold and the evolution of shake-up into shake-down. United States. doi:10.1103/PHYSREVA.73.022709.
Hergenhahn, U., Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, 85748 Garching, De Fanis, A., Pruemper, G., Ueda, K., Kazansky, A. K., Kabachnik, N. M., Fakultaet fuer Physik, Universitaet Bielefeld, 33615 Bielefeld, and Institute of Nuclear Physics, Moscow State University, Moscow 119992. Wed . "Population of individual Ne 1s{sup -1}np Rydberg states measured across the 1s ionization threshold and the evolution of shake-up into shake-down". United States. doi:10.1103/PHYSREVA.73.022709.
@article{osti_20974580,
title = {Population of individual Ne 1s{sup -1}np Rydberg states measured across the 1s ionization threshold and the evolution of shake-up into shake-down},
author = {Hergenhahn, U. and Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, 85748 Garching and De Fanis, A. and Pruemper, G. and Ueda, K. and Kazansky, A. K. and Kabachnik, N. M. and Fakultaet fuer Physik, Universitaet Bielefeld, 33615 Bielefeld and Institute of Nuclear Physics, Moscow State University, Moscow 119992},
abstractNote = {New high-resolution experimental results on Ne 1s near-threshold photoionization with subsequent decay into a 2p{sup 4}({sup 1}D{sub 2})n{sup '}p or 2p{sup 4}({sup 1}D{sub 2}){epsilon}{sup '}p state are presented. The population of Rydberg states up to n{sup '}=12 is determined as a function of excess energy. These data allow one to track in detail the transition from resonant Auger decay going along with shake-up of the spectator electron to shake-down and photoionization with recapture of the photoelectron. Results are in good agreement with a time-dependent quantum mechanical theory of Auger decay in the presence of a slow photoelectron.},
doi = {10.1103/PHYSREVA.73.022709},
journal = {Physical Review. A},
number = 2,
volume = 73,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
  • We have analyzed high resolution (EUV) spectra of HeI and HeII originating from e{sup -}, H{sup +}, H{sub 2}{sup +} and H{sub 3}{sup +} bombardment of He gas. From these data excitation and ionization-excitation cross sections have been obtained by the HeI (1snp){sup 1}P{sup o} {yields} (1s2){sup 1}S + h{nu} and HeII (np){sup 2}P{sup o}-(1s){sup 2}S + h{nu} Rydberg series with main quantum numbers from n=2 to 10, respectively. The determination of the individual line intensities has been accomplished using the IRAF one dimensional spectroscopy package installed on the Physics Department`s HP9000 system. The cross sections for n{>=}4 presented heremore » are reported for the first time. The up manifolds have been studied as a function of the projectile charge and velocity and number of scattering centers. Theoretically we have parametrized the cross sections in terms of first order, second order and interference contributions. We have also tested sum rules, by integrating over all np states. The dynamical Stark mixing among HeII ns and np states has also been investigated. A detailed discussion of the intensity distribution at high np states is presented for different means of excitation.« less
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  • The energy dependencies of the intensities and angular distribution parameters {beta} of the resonant Auger final states 4p{sup 4}({sup 1}D)np (n=5,6) of Kr were determined experimentally in the excitation-energy region of the overlapping 3d{sub 3/2}{sup -1}5p and 3d{sub 5/2}{sup -1}6p resonances. The experimental results were compared with the outcome of multiconfiguration Dirac-Fock calculations. Combining experimental and calculated results allowed us to study interference effects between the direct and several resonant channels that populate the 4p{sup 4}({sup 1}D)np states. The inclusion of the direct channel was crucial in order to reproduce the observed energy behavior of the angular distribution parameters. Itmore » was also important to take into account experimentally observed shake transitions.« less
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