TY  - JOUR
AU  - Noguera, S.
AU  - Vento, V.
PY  - 2010
DA  - 2010//
TI  - The pion transition form factor and the pion distribution amplitude
T2  - Eur. Phys. J. A
JO  - European Physical Journal A
SP  - 197
EP  - 205
VL  - 46
IS  - 2
PB  - Springer
AB  - Recent BaBar data on the pion transition form factor, whose Q(2)-dependence is much steeper then predicted by asymptotic Quantum Chromodynamics (QCD), have caused a renewed interest in its theoretical description. We present here a formalism based on a model-independent description for low photon virtuality and a high photon virtuality description based on QCD, which match at a scale Q(0). The high photon virtuality description incorporates a flat pion distribution amplitude, phi(x) = 1, at the matching scale Q(0) and QCD evolution from Q(0) to Q > Q(0). The flat pion distribution is connected, through soft pion theorems and chiral symmetry, to the pion valence parton distribution at the same low scale Q(0). The procedure leads to a good description of the data, and by incorporating additional twist-three effects, to an excellent description of the data.
SN  - 1434-6001
UR  - http://arxiv.org/abs/1001.3075
UR  - https://doi.org/10.1140/epja/i2010-11029-6
DO  - 10.1140/epja/i2010-11029-6
LA  - English
N1  - ISI:000284869600005
ID  - Noguera+Vento2010
ER  -