Johan Bijnens
Professor, Deputy Head of Division
Exploring light-cone sum rules for pion and kaon form factors
Author
Summary, in English
We analyze the higher-twist effects and the SU(3)-flavor symmetry breaking in the correlation functions used to calculate form factors of pseudoscalar mesons in the QCD light-cone sum rule approach. It is shown that the Ward identities for these correlation functions yield relations between twist-4 two-and three-particle distribution amplitudes. In addition to the relations already obtained from the QCD equations of motions, we have found a new one. With the help of these relations, the twist-4 contribution to the light-cone sum rule for the. pion electromagnetic form factor: is reduced to a very simple form. Simultaneously, we correct a sign error in an earlier calculation. The updated light-cone sum rule prediction for the pion form factor at intermediate momentum transfers is compared with the recent Jefferson Lab data. Furthermore, from the correlation functions with strange-quark currents the kaon electromagnetic form factor and the K --> pi weak transition form factors are predicted with O(m(s)) similar to O(m(K)(2)) accuracy.
Department/s
- Theoretical Particle Physics - Has been reorganised
Publishing year
2002
Language
English
Pages
67-79
Publication/Series
European Physical Journal C. Particles and Fields
Volume
26
Issue
1
Document type
Journal article
Publisher
Springer
Topic
- Subatomic Physics
Status
Published
ISBN/ISSN/Other
- ISSN: 1434-6044