The gV sigma gamma coupling constants in hadron electrodynamics


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Rekalo M., Tomasi-Gustafsson E.

NUCLEAR PHYSICS A, vol.725, pp.116-126, 2003 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 725
  • Publication Date: 2003
  • Doi Number: 10.1016/s0375-9474(03)01605-1
  • Title of Journal : NUCLEAR PHYSICS A
  • Page Numbers: pp.116-126

Abstract

Recent measurements of the branching ratios for the decays omega --> pi(0) pi(0)gamma and rho(0) --> pi(0)pi(0)gamma lead to coupling constants of the Vsigmagamma interaction (V is a vector meson) one order of magnitude smaller than previously assumed to describe the threshold cross section of gamma + p --> p + rho(0) and the HERMES effect. The new g(Vsigmagamma)(2) a couplings are in contradiction with the predictions of the QCD sum rules, but are in agreement with vector meson dominance estimation of the sigma --> gammagamma width. (C) 2003 Elsevier B.V. All rights reserved.