by
DrVicente Vento(Universidad de Valencia - IFIC)
→
Europe/Rome
Aula Edificio 22 (Laboratori Nazionali di Frascati)
Aula Edificio 22
Laboratori Nazionali di Frascati
Description
Vicente Vento, Universidad de Valencia - IFIC
BABAR data on the pion transition form factor have caused concern about the theoretical description thus far employed.
We present here a formalism based on a low energy description, supported by constituent quark models, and a high energy description which match at a scale of $\sim 1 $ GeV. The high energy description incorporates a flat pion distribution amplitude at the matching scale $Q_0$, QCD evolution for $Q > Q_0$ and higher twist effects. The procedure produces an excellent description of the data.