Positronium formation at low temperatures: the role of trapped electrons

被引：132

作者：

Hirade, T ^{[1
]}

Maurer, FHJ

Eldrup, M

机构：

[1] Japan Atom Energy Res Inst, Dept Mat Sci, Tokai, Ibaraki 3191195, Japan

[2] Lund Univ, Ctr Chem & Chem Engn, Lund Inst Technol, Dept Polymer Sci & Engn, SE-22100 Lund, Sweden

[3] Riso Natl Lab, Dept Mat Res, DK-4000 Roskilde, Denmark

来源：

RADIATION PHYSICS AND CHEMISTRY | 2000年 / 58卷 / 5-6期

关键词：

positronium; trapped electrons; low temperature; gamma-irradiation; visible light; polymer;

D O I：

10.1016/S0969-806X(00)00201-2

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Measurements have been carried out of electron spin densities (by electron spin resonance technique) and positronium (Ps) formation probability as functions of Co-60 gamma-irradiation dose in poly(methyl methacrylate) and linear poly(ethylene) at 77 K. We observe a linear relationship between the enhancement of the Ps formation and the density of trapped electrons in both polymers. This clear correlation strongly supports the previous suggestion by the authors that the increase in Ps formation with time (that has been observed at low temperatures for a number of polymers) can be explained as a reaction of free positrons with trapped electrons produced by the previously injected positrons. (C) 2000 Elsevier Science Ltd. All rights reserved.

引用

页码：465 / 471

页数：7

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