Progress with the Schwinger multichannel method in positron-molecule scattering

被引：47
作者：
de Carvalho, CRC
Varella, MTD
Lima, MAP [1 ]
da Silva, EP
Germano, JSE
机构：
[1] Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil
[2] Univ Fed Ceara, Dept Fis, BR-60455760 Fortaleza, Ceara, Brazil
[3] CTA, Ctr Techn Aerospacial, Dept Fis, Inst Tecnol Aeronaut, BR-12228900 Sao Jose Dos Campos, Brazil
来源：
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS | 2000年 / 171卷 / 1-2期
基金：
巴西圣保罗研究基金会;
关键词：
positron; annihilation; positron-molecule scattering;
D O I：
10.1016/S0168-583X(00)00036-7
中图分类号：
TH7 [仪器、仪表];
学科分类号：
0804 ; 080401 ; 081102 ;
摘要：
We report calculations for low-energy positron-C2H2 and -N-2 scattering obtained through the Schwinger multichannel method (SMC). Integral and differential cross-sections and the annihilation parameter, Z(eff), are presented. For nitrogen, evidence of a Ramsauer-Townsend minimum and the possibility of overcorrelation in the scattering configuration space are discussed. Annihilation probability densities (APD) calculated for He and H-2 Seem to bring indirect support to a model previously proposed to explain why acetylene, unlike nitrogen, presents very high low-energy annihilation rates. (C) 2000 Elsevier Science B.V. All rights reserved.
引用
收藏
页码：33 / 46
页数：14
相关论文
共 24 条
  • [1] BRANDT W, 1983, INT SCH PHYSICS E FE
  • [2] TOTAL SCATTERING CROSS-SECTIONS FOR LOW-ENERGY POSITRONS IN THE MOLECULAR GASES H-2,N-2,CO2,O-2 AND CH4
    CHARLTON, M
    GRIFFITH, TC
    HEYLAND, GR
    WRIGHT, GL
    [J]. JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS, 1983, 16 (02) : 323 - 341
  • [3] R-MATRIX CALCULATIONS OF VIBRATIONALLY RESOLVED POSITRON N2 SCATTERING CROSS-SECTIONS
    DANBY, G
    TENNYSON, J
    [J]. JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS, 1991, 24 (15) : 3517 - 3529
  • [4] ZEFF ACCORDING TO THE SCHWINGER MULTICHANNEL METHOD IN POSITRON SCATTERING
    DASILVA, EP
    GERMANO, JSE
    LIMA, MAP
    [J]. PHYSICAL REVIEW A, 1994, 49 (03): : R1527 - R1530
  • [5] Annihilation dynamics of positrons in molecular environments: Theoretical study of low-energy positron-C2H4 scattering
    daSilva, EP
    Germano, JSE
    Lima, MAP
    [J]. PHYSICAL REVIEW LETTERS, 1996, 77 (06) : 1028 - 1031
  • [6] DECARVALHO CRC, 1999, UNPUB PHYS REV LETT
  • [7] FRASER PA, 1968, ADV ATOM MOL PHYS, V4, P63
  • [8] SCHWINGER MULTICHANNEL METHOD FOR POSITRON-MOLECULE SCATTERING
    GERMANO, JSE
    LIMA, MAP
    [J]. PHYSICAL REVIEW A, 1993, 47 (05): : 3976 - 3982
  • [9] POSITRON LIFETIME SPECTRA FOR GASES
    HEYLAND, GR
    CHARLTON, M
    GRIFFITH, TC
    WRIGHT, GL
    [J]. CANADIAN JOURNAL OF PHYSICS, 1982, 60 (04) : 503 - 516
  • [10] TOTAL-CROSS-SECTION MEASUREMENTS FOR POSITRONS AND ELECTRONS COLLIDING WITH H-2, N-2, AND CO2
    HOFFMAN, KR
    DABABNEH, MS
    HSIEH, YF
    KAUPPILA, WE
    POL, V
    SMART, JH
    STEIN, TS
    [J]. PHYSICAL REVIEW A, 1982, 25 (03) : 1393 - 1403
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