出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：Semi-exclusive and exclusive processes are becoming more and more important in high energy
physics since they are excellently suited to study the internal hadronic structure. To analyze such
processes the knowledge of the hadron distribution amplitudes, which are universal for different
reactions, is essential. Only rather indirect information on these nonperturbative functions can be
obtained from measurements. In this work we report on a lattice QCD computation of moments
of nucleon distribution amplitudes using suitable three-quark operators. However, these operators
have to be renormalized and the mixing is even more complicated than in the continuum. Using
the symmetry group of the hypercubic lattice we therefore derive and implement irreducibly transforming
three-quark operators, which allow us to control the mixing pattern and will finally lead
to quantitative predictions in the MS scheme. We present preliminary results for leading-twist and
next-to-leading twist nucleon distribution amplitudes based on the QCDSF/UKQCD simulations
with 2 flavors of dynamical clover fermions.
