The pi N N and pi N N(1535) couplings in QCD
Journal
Phys. Rev.
Journal Volume
C59
Pages
442-450
Date Issued
1998-09
Author(s)
Abstract
We study the two point correlation function of two nucleon currents sandwiched between the vacuum and the pion state. The light cone QCD sum rules are derived for the [Formula Presented] coupling [Formula Presented] and the [Formula Presented] coupling [Formula Presented] The contribution from the excited states and the continuum is subtracted cleanly through the double Borel transform with respect to the two external momenta [Formula Presented] We first improve the original sum rule for [Formula Presented] and determine the value of the pion wave function [Formula Presented] which is a fundamental nonperturbative quantity similar to the quark condensate. Our calculation shows that the [Formula Presented] coupling is strongly suppressed. © 1999 The American Physical Society.
Type
journal article