Izabela Babiarz
(Institute of Nuclear Physics, Polish Academy of Sciences)Prof.
Victor P. Goncalves
(Instituto de Fisica e Matematica Universidade Federal de Pelotas (UFPel))Dr
Roman Pasechnik
(Department of Astronomy and Theoretical Physics, Lund University)Dr
Wolgang Sch\"afer
(nstitute of Nuclear Physics, Polish Academy of Sciences)Prof.
Antoni Szczurek
(Institute of Nuclear Physics, Krakow and Rzeszow University, Rzeszow)
We discuss transition form factor for both virtual photons. The general formula is given. We use different models for the wave function (LFQM or the ones obtained from the solution of the Schr\"odinger equation for different potentials: harmonic oscillator, Cornell, logarithmic, power-law and Buchm\"uller-Tye).
We compare our results to the BaBar experimental data for , for one real and one virtual photon. We discuss approaching of or to their asymptotic value
predicted by Brodsky and Lepage formalizm.We discuss applicability of the collinear and/or massless limit and delayed onset of asymptotic behaviour.
We present some examples of two-dimensional distributions for .
A factorization breaking measure is proposed and factorization breaking effects are quantified and shown to be almost model independent.
Izabela Babiarz
(Institute of Nuclear Physics, Polish Academy of Sciences)
Prof.
Victor P. Goncalves
(Instituto de Fisica e Matematica Universidade Federal de Pelotas (UFPel))
Dr
Roman Pasechnik
(Department of Astronomy and Theoretical Physics, Lund University)
Dr
Wolgang Sch\"afer
(nstitute of Nuclear Physics, Polish Academy of Sciences)
Prof.
Antoni Szczurek
(Institute of Nuclear Physics, Krakow and Rzeszow University, Rzeszow)