Theory Seminar

KEK 素粒子原子核研究所・理論セミナー

TITLE Axial anomaly and transition form factors of pseudoscalar mesons
(英語 / in English)
SPEAKER Dr. Yaroslav klopot
Dubna, JINR
DATE: March 14 (Wed.) 11:00 − 12:00
PLACE: Kenkyu-Honkan 1F, Meeting Room 1


We study photon-meson transition form factors of pseudoscalar mesons by means of anomaly sum rule, a relation which follows from dispersive representation of axial anomaly. As the anomaly sum rule is an exact relation (perturbative and nonperturbative corrections are absent), it allows us to study the interplay between possible corrections to continuum and to lower states within method which does not rely on QCD factorization hypothesis. We show, relying on the recent data of the BaBar Collaboration, that while the relative correction to continuum is quite small, the correction to continuum can dramatically change the pion form factor. In the octet channel, where a strong mixing between $\eta$ and $\eta'$ is present, the anomaly sum rule allows to get additional constraints for the mixing parameters. The notion of quark-hadron duality in our approach is discussed.