Izlaganje sa skupa
Accessing the pion distribution amplitude through the CLEO and E791 data
Alexander P. Bakulev
; Joint Institute for Nuclear Research, Bogoliubov Laboratory of Theoretical Physics, 141920, Moscow Region, Dubna, Russia
S. V. Mikhailov
; Joint Institute for Nuclear Research, Bogoliubov Laboratory of Theoretical Physics, 141920, Moscow Region, Dubna, Russia
N. G. Stefanis
; Institut für Theoretische Physik II, Ruhr-Universität Bochum, I-44780 Bochum, Germany
Sažetak
Using QCD perturbation theory in NLO and light-cone QCD sum rules, we extract from the CLEO experimental results the data on the Fγ ∗γπ (Q2) transition form factor constraints, on the Gegenbauer coefficients a2 and a4, as well as on the inverse moment (x −1)π of the pion distribution amplitude. We show that both the asymptotic and the Chernyak–Zhitnitsky pion distribution amplitudes are excluded at the 3σ- and 4σ-level, respectively, while the data confirm the end-point suppressed shape of the pion DA that we previously obtained with QCD sum rules and nonlocal condensates. These findings are also supported by the data of the Fermilab E791 experiment on diffractive di-jet production.
Ključne riječi
transition form factor; pion distribution amplitude; QCD sum rules; factorization; renormalization group evolutio
Hrčak ID:
305697
URI
Datum izdavanja:
1.6.2004.
Posjeta: 93 *