Second moment of the pion's distribution amplitude

/ Authors

M. Göckeler, R. Horsley, D. Pleiter, P. Rakow, A. Schäfer, G. Schierholz, W. Schroers, J. Zanotti, Qcdsf

/ Abstract

We present preliminary results from the QCDSF/UKQCD collaborations for the second moment of the pion's distribution amplitude with two flavours of dynamical fermions. We use nonperturbatively determined renormalisation coefficients to convert our results to the MS ¯ scheme at 5 GeV 2 . Employing a linear chiral extrapolation from our large pion masses > 550 MeV , we find 〈 ξ 2 〉 = 0.281 ( 28 ) , leading to a value of a 2 = 0.236 ( 82 ) for the second Gegenbauer moment.

DOI: 10.1016/j.nuclphysbps.2006.08.064