Two-current correlations in the pion in the Nambu and Jona-Lasinio model

Abstract

We present an analysis of two-current correlations for the pion in the Nambu--Jona-Lasinio model, with Pauli--Villars regularization. We provide explicit expressions in momentum space for two-current correlations corresponding to the zeroth component of the vector Dirac bilinear in the quark vertices, which has been evaluated on the lattice. The numerical results show a remarkable qualitative agreement with recent lattice data. The factorization approximation into one-body currents is discussed.

Comments: 19 pages, 9 figures. arXiv admin note: text overlap with arXiv:1909.09530