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Madesis I, Laoutaris A, Zouros TJM, Benis EP, Gao JW, Dubois A. Pauli Shielding and Breakdown of Spin Statistics in Multielectron Multi-Open-Shell Dynamical Atomic Systems. PHYSICAL REVIEW LETTERS 2020; 124:113401. [PMID: 32242719 DOI: 10.1103/physrevlett.124.113401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 02/10/2020] [Accepted: 02/22/2020] [Indexed: 06/11/2023]
Abstract
We report on C^{3+}(1s2ℓ2ℓ^{'} ^{2S+1}L)-resolved cross sections of electron capture in collisions of swift C^{4+}(1s2s ^{3}S) ions with helium and hydrogen. The study focuses on the formation of doubly excited triply open-shell C^{3+}(1s2s2p) ^{4}P and ^{2}P_{±} states with emphasis on the ratio R of their cross sections as a measure of spin statistics. Using zero-degree Auger projectile spectroscopy and a three-electron close-coupling semiclassical approach, we resolve a long-standing puzzle and controversy on the value of R and on the effect of cascades, to clarify the underlying physics. The present results invalidate the frozen core approximation generally used in the past when considering electron capture in multielectron multi-open-shell quantum systems. A distinctive screening effect due to the Pauli exclusion principle (Pauli shielding) is proposed to account for the value of R, consistent with our findings.
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Affiliation(s)
- I Madesis
- Department of Physics, University of Crete, GR-70013 Heraklion, Greece and Tandem Accelerator Laboratory, Institute of Nuclear and Particle Physics, NCSR "Demokritos", GR-15310 Agia Paraskevi, Greece
| | - A Laoutaris
- Department of Physics, University of Crete, GR-70013 Heraklion, Greece and Tandem Accelerator Laboratory, Institute of Nuclear and Particle Physics, NCSR "Demokritos", GR-15310 Agia Paraskevi, Greece
| | - T J M Zouros
- Department of Physics, University of Crete, GR-70013 Heraklion, Greece and Tandem Accelerator Laboratory, Institute of Nuclear and Particle Physics, NCSR "Demokritos", GR-15310 Agia Paraskevi, Greece
| | - E P Benis
- Department of Physics, University of Ioannina, GR-45110 Ioannina, Greece
| | - J W Gao
- Institute of Applied Physics and Computational Mathematics, 100088 Beijing, China, Laser Fusion Research Center, China Academy of Engineering Physics, 621900 Mianyang, China and Sorbonne Université, CNRS, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France
| | - A Dubois
- Sorbonne Université, CNRS, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France
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Zhang SF, Fischer D, Schulz M, Voitkiv AB, Senftleben A, Dorn A, Ullrich J, Ma X, Moshammer R. Two-center interferences in dielectronic transitions in H2(+) + He collisions. PHYSICAL REVIEW LETTERS 2014; 112:023201. [PMID: 24484006 DOI: 10.1103/physrevlett.112.023201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Indexed: 06/03/2023]
Abstract
Molecular two-center interferences in a collision induced excitation of H2(+) projectile ions, with simultaneous ionization of helium target atoms, are investigated in a kinematically complete experiment. In the process under investigation, the helium atom is singly ionized and simultaneously the molecular hydrogen ion is dissociated. Different collision mechanisms are identified and interference fringes emerging from a correlated first-order mechanism and from an independent second-order process are observed.
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Affiliation(s)
- S F Zhang
- Institute of Modern Physics, Chinese Academy of Sciences, 730000 Lanzhou, China and Max-Planck-Institute for Nuclear Physics, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - D Fischer
- Max-Planck-Institute for Nuclear Physics, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - M Schulz
- Max-Planck-Institute for Nuclear Physics, Saupfercheckweg 1, D-69117 Heidelberg, Germany and Physics Department and LAMOR, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
| | - A B Voitkiv
- Max-Planck-Institute for Nuclear Physics, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - A Senftleben
- Max-Planck-Institute for Nuclear Physics, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - A Dorn
- Max-Planck-Institute for Nuclear Physics, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - J Ullrich
- Max-Planck-Institute for Nuclear Physics, Saupfercheckweg 1, D-69117 Heidelberg, Germany and Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116, Braunschweig, Germany
| | - X Ma
- Institute of Modern Physics, Chinese Academy of Sciences, 730000 Lanzhou, China
| | - R Moshammer
- Max-Planck-Institute for Nuclear Physics, Saupfercheckweg 1, D-69117 Heidelberg, Germany
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Bultel A, van Ootegem B, Bourdon A, Vervisch P. Influence of Ar(2)+ in an argon collisional-radiative model. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2002; 65:046406. [PMID: 12006022 DOI: 10.1103/physreve.65.046406] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2001] [Revised: 10/31/2001] [Indexed: 05/23/2023]
Abstract
A nonlinear time-dependent collisional-radiative model for recombining argon is presented. Reactions involving Ar(2)+ are taken into account and their influence is discussed. It is shown that Ar(2)+ may increase the time to reach the quasi-steady-state by a factor of 100. The calculation of the recombination rate coefficient at the quasi-steady-state is presented. An analytical expression is derived and compared with existing literature values. The importance of the increase of the quasi-steady-state time is illustrated by comparisons of excited levels population densities distribution measured in a fast moving plasma where the mechanical time scale is sufficiently short to provide a time-dependent chemistry in a reference frame moving with the flow. The high sensitivity of the results towards the electron number density is pointed out. Finally, the influence of the processes involving Ar(2)+ on the excitation temperature is discussed.
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Affiliation(s)
- Arnaud Bultel
- CORIA, UMR CNRS 6614, Université de Rouen, Site Universitaire du Madrillet, Avenue de l'Université, 76801 Saint-Etienne du Rouvray Cedex, France.
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Kollmus H, Moshammer R, Olson RE, Hagmann S, Schulz M, Ullrich J. Simultaneous projectile-target ionization: a novel approach to (e, 2e) experiments on ions. PHYSICAL REVIEW LETTERS 2002; 88:103202. [PMID: 11909353 DOI: 10.1103/physrevlett.88.103202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2001] [Indexed: 05/23/2023]
Abstract
A kinematically complete experiment for simultaneous ionization of a projectile and target has been performed for 3.6 MeV/u C2+ on He collisions measuring the final vector momenta of the He1+ recoil ion and of two electrons (projectile, target) in coincidence with the emerging C3+ projectile. The feasibility of an event-by-event separation of the various reaction channels, among them the ionization of C2+ by the interaction with a quasifree target electron, is demonstrated in agreement with six-body classical trajectory Monte Carlo calculations, paving the way to kinematically complete electron-ion scattering experiments.
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Affiliation(s)
- H Kollmus
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
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Montenegro EC, Santos ACF, Melo WS, Sant'Anna MM, Sigaud GM. Effective strength of the electron-electron interaction in simultaneous projectile and target ionization. PHYSICAL REVIEW LETTERS 2002; 88:013201. [PMID: 11800942 DOI: 10.1103/physrevlett.88.013201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2001] [Indexed: 05/23/2023]
Abstract
The determination of the right balance between the strong-field interaction of the screened target nucleus and the two-center electron-electron interaction has been controversial since the early attempts to describe the stripping of light, swift ions, by heavy targets. In this work, we find a region of influence for the electron-electron contribution which clearly indicates that this interaction is an essential contribution to the stripping process for both light and heavy targets.
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Affiliation(s)
- E C Montenegro
- Departamento de Física, Pontifícia Universidade Católica do Rio de Janeiro, Caixa Postal 38071, Rio de Janeiro 22452-970, Brazil
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McGuire JH, Straton JC, Wang J, Wang YD, Weaver OL, Corchs SE, Rivarola RD. Independent center, independent electron approximation for dynamics of molecules and clusters. J Chem Phys 1996. [DOI: 10.1063/1.472816] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Forest JL, Tanis JA, Ferguson SM, Haar RR, Lifrieri K, Plano VL. Single and double ionization of helium by intermediate-to-high-velocity He+ projectiles. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1995; 52:350-356. [PMID: 9912253 DOI: 10.1103/physreva.52.350] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Wang J, McGuire JH, Montenegro EC. Impact-parameter dependence for collisions of atoms with projectiles carrying electrons. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1995; 51:504-512. [PMID: 9911609 DOI: 10.1103/physreva.51.504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Montenegro EC, Zouros TJ. Relationship between the Born and impulse approximations for the antiscreening process. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1994; 50:3186-3191. [PMID: 9911263 DOI: 10.1103/physreva.50.3186] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Dörner R, Mergel V, Ali R, Buck U, Cocke CL, Froschauer K, Jagutzki O, Lencinas S, Meyerhof WE, Nüttgens S, Olson RE, Schmidt-Böcking H, Spielberger L, Tökesi K, Ullrich J, Unverzagt M, Wu W. Electron-electron interaction in projectile ionization investigated by high resolution recoil ion momentum spectroscopy. PHYSICAL REVIEW LETTERS 1994; 72:3166-3169. [PMID: 10056124 DOI: 10.1103/physrevlett.72.3166] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Wu W, Wong KL, Ali R, Chen CY, Cocke CL, Frohne V, Giese JP, Raphaelian M, Walch B, Dörner R, Mergel V, Schmidt-Böcking H, Meyerhof WE. Experimental separation of electron-electron and electron-nuclear contributions to ionization of fast hydrogenlike ions colliding with He. PHYSICAL REVIEW LETTERS 1994; 72:3170-3173. [PMID: 10056125 DOI: 10.1103/physrevlett.72.3170] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Montenegro EC, Melo WS, Meyerhof WE. Intermediate-velocity atomic collisions. VI. Screening, antiscreening, and related processes in He++( H2, He). PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1993; 48:4259-4266. [PMID: 9910127 DOI: 10.1103/physreva.48.4259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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