Vacuum condensates and the pion wave functions in the nonlocal chiral model

摘要

We use the simple instanton motivated Nambu Jona-Lasinio - type model tocalculate a twist 3 pseudoscalar pion light cone wave function. Usingnormalisation condition for this wave function we calculate the quarkcondensate and also the gluon condensate, which agree with the phenomenologicalvalues for these quantities. Since we can compute also the k_T^2 dependence ofthe light cone wave functions, we calculate k_T^2 moments of the pseudo-scalarand axial-vector wave functions which are related to the mixed vacuumcondensates. This allows us to extract the condensates and compare them withexisting estimates.