Delocalized positronium in alkali-halide crystals: analysis of possible lattice-scattering processes

Authors
Citation
Iv. Bondarev, Delocalized positronium in alkali-halide crystals: analysis of possible lattice-scattering processes, PHYS LETT A, 291(1), 2001, pp. 39-45
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
PHYSICS LETTERS A
ISSN journal
0375-9601 → ACNP
Volume
291
Issue
1
Year of publication
2001
Pages
39 - 45
Database
ISI
SICI code
0375-9601(20011126)291:1<39:DPIACA>2.0.ZU;2-9
Abstract
A theoretical analysis of possible lattice-scattering processes for delocal ized positronium atoms (Ps) in alkali-halide crystals is presented. Optic d eformation-potential scattering, unless forbidden by selection rules, is sh own to renormalize the acoustic deformation-potential constant of Ps thereb y dramatically broadening its momentum distribution with increasing tempera ture. This explains the anomalous temperature broadening of the momentum di stribution of Ps in crystalline MgF2 and its absence in alpha -SiO2 as rece ntly observed. An effect analogous to that in MgF2 is predicted for beta -S iO2 above the alpha-beta phase transition at 846 K. (C) 2001 Published by E lsevier Science B.V.