1
|
Angular Distribution of Characteristic Radiation Following the Excitation of He-Like Uranium in Relativistic Collisions. ATOMS 2021. [DOI: 10.3390/atoms9020020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In this paper, we present an experimental and theoretical study of excitation processes for the heaviest stable helium-like ion, that is, He-like uranium occurring in relativistic collisions with hydrogen and argon targets. In particular, we concentrate on angular distributions of the characteristic Kα radiation following the K → L excitation of He-like uranium. We pay special attention to the magnetic sub-level population of the excited 1s2lj states, which is directly related to the angular distribution of the characteristic Kα radiation. We show that the experimental data can be well described by calculations taking into account the excitation by the target nucleus as well as by the target electrons. Moreover, we demonstrate for the first time an important influence of the electron-impact excitation process on the angular distributions of the Kα radiation produced by excitation of He-like uranium in collisions with different targets.
Collapse
|
2
|
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.
Collapse
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
| |
Collapse
|
3
|
Abstract
The use of mixed-state ionic beams in collision dynamics investigations is examined. Using high resolution Auger projectile spectroscopy involving He-like ( 1 s 2 1 S , 1 s 2 s 3 , 1 S ) mixed-state beams, the spectrum contributions of the 1 s 2 s 3 S metastable beam component is effectively separated and clearly identified. This is performed with a technique that exploits two independent spectrum measurements under the same collision conditions, but with ions having quite different metastable fractions, judiciously selected by varying the ion beam charge-stripping conditions. Details of the technique are presented together with characteristic examples. In collisions of 4 MeV B 3 + with H 2 targets, the Auger electron spectrum of the separated 1 s 2 s 3 S boron beam component allows for a detailed analysis of the formation of the 1 s 2 s ( 3 S ) n l 2 L states by direct n l transfer. In addition, the production of hollow 2 s 2 p 1 , 3 P doubly- and 2 s 2 p 2 2 D triply-excited states, by direct excitation and transfer-excitation processes, respectively, can also be independently studied. In similar mixed-state beam collisions of 15 MeV C 4 + with H 2 , He, Ne and Ar targets, the contributions of the 1 s 2 , 1 s 2 s 3 , 1 S beam components to the formation of the 2 s 2 p 3 , 1 P states by double-excitation, 1 s → 2 p excitation and transfer-loss processes can be clearly identified, facilitating comparisons with theoretical calculations.
Collapse
|
4
|
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.
Collapse
Affiliation(s)
- E C Montenegro
- Departamento de Física, Pontifícia Universidade Católica do Rio de Janeiro, Caixa Postal 38071, Rio de Janeiro 22452-970, Brazil
| | | | | | | | | |
Collapse
|
5
|
Gorczyca TW, Pindzola MS. Resonance enhancement of electron-projectile excitation in collisions of O5+ ions with H2 targets. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1995; 52:859-861. [PMID: 9912312 DOI: 10.1103/physreva.52.859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
6
|
Sulik B, Ricz S, Kádár I, Xiao G, Schiwietz G, Sommer K, Grande P, Köhrbrück R, Grether M, Stolterfoht N. Dominant two-center electron-electron interactions in collisions of 120-MeV Ne6+ ions with gas targets. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1995; 52:387-391. [PMID: 9912259 DOI: 10.1103/physreva.52.387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
7
|
Shimakura N, Yamada S, Suzuki S, Kimura M. Low-energy collisions of O5+ ions with He atoms: Single-electron capture, projectile excitation, and transfer excitation and ionization. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1995; 51:2989-2996. [PMID: 9911933 DOI: 10.1103/physreva.51.2989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
8
|
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]
|
9
|
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]
|
10
|
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]
|
11
|
DuBois RD, Toburen LH, Middendorf ME, Jagutzki O. Systematics and scaling of differential ionization cross sections in multicharged ion-atom collisions. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1994; 49:350-356. [PMID: 9910238 DOI: 10.1103/physreva.49.350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
12
|
Deveney EF, Kessel QC, Fuller RJ, Reaves MP, Bellantone RA, Shafroth SM, Jones N. Projectile-Auger-electron spectra of C3+ following 12-MeV collisions with He targets. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1993; 48:2926-2933. [PMID: 9909940 DOI: 10.1103/physreva.48.2926] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
13
|
Montenegro EC, Belkacem A, Spooner DW, Meyerhof WE, Shah MB. Impact-parameter dependence of the electron-electron interaction in (Li2+,C5+)+(H2,He) electron loss. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1993; 47:1045-1051. [PMID: 9909026 DOI: 10.1103/physreva.47.1045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
14
|
Montenegro EC, Melo WS, Meyerhof WE. Separation of the screening and antiscreening effects in the electron loss of He+ on H2 and He. PHYSICAL REVIEW LETTERS 1992; 69:3033-3036. [PMID: 10046708 DOI: 10.1103/physrevlett.69.3033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
15
|
Lee DH, Zouros TJ, Sanders JM, Richard P, Anthony JM, Wang YD, McGuire JH. K-shell ionization of O4+ and C2+ ions in fast collisions with H2 and He gas targets. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1992; 46:1374-1387. [PMID: 9908259 DOI: 10.1103/physreva.46.1374] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
16
|
Montenegro EC, Sigaud GM, Meyerhof WE. Intermediate-velocity atomic collisions. V. Electron capture and loss in C3+ and O5+ collisions with H2 and He. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1992; 45:1575-1582. [PMID: 9907142 DOI: 10.1103/physreva.45.1575] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
17
|
Montenegro EC, Meyerhof WE. Target screening effect on the projectile electron-loss probability. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1991; 44:7229-7233. [PMID: 9905864 DOI: 10.1103/physreva.44.7229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
18
|
Hülskötter H, Feinberg B, Meyerhof WE, Belkacem A, Alonso JR, Blumenfeld L, Dillard EA, Gould H, Guardala N, Krebs GF, McMahan MA, Rhoades-Brown ME, Rude BS, Schweppe J, Spooner DW, Street K, Thieberger P, Wegner HE. Electron-electron interaction in projectile electron loss. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1991; 44:1712-1724. [PMID: 9906139 DOI: 10.1103/physreva.44.1712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
19
|
Meyerhof WE, Hülskötter H, Dai Q, McGuire JH, Wang YD. Projectile electron loss with a molecular hydrogen target. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1991; 43:5907-5918. [PMID: 9904919 DOI: 10.1103/physreva.43.5907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
20
|
Montenegro EC, Meyerhof WE. Sum rules and electron-electron interaction in two-center scattering. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1991; 43:2289-2293. [PMID: 9905276 DOI: 10.1103/physreva.43.2289] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
21
|
DePaola BD, Parameswaran R, Axmann WJ. High-resolution state-selective study of transfer with excitation in the F8++H2 system. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1990; 41:6533-6535. [PMID: 9903058 DOI: 10.1103/physreva.41.6533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
22
|
Lee DH, Richard P, Zouros TJ, Sanders JM, Shinpaugh JL, Hidmi H. Binary-encounter electrons observed at 0 degrees in collisions of 1-2-MeV/amu H+, C6+, N7+, O8+, and F9+ ions with H2 and He targets. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1990; 41:4816-4823. [PMID: 9903703 DOI: 10.1103/physreva.41.4816] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
23
|
Badnell NR. Auger emission following resonant transfer excitation in collisions of F8+ with H2. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1990; 41:3555-3558. [PMID: 9903525 DOI: 10.1103/physreva.41.3555] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
24
|
Hahn Y, Ramadan H. Uncorrelated transfer excitation collisions at high energies. PHYSICAL REVIEW. A, GENERAL PHYSICS 1989; 40:6206-6209. [PMID: 9902008 DOI: 10.1103/physreva.40.6206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
25
|
Hülskötter H, Meyerhof WE, Dillard E, Guardala N. Evidence for electron-electron interaction in projectile K-shell ionization. PHYSICAL REVIEW LETTERS 1989; 63:1938-1941. [PMID: 10040719 DOI: 10.1103/physrevlett.63.1938] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|