Strong coupling constant of negative parity nucleon with $\pi$ meson in light cone QCD sum rules

TL;DR

This paper estimates the strong coupling constant between negative parity nucleons and pions using light cone QCD sum rules, presenting a method to eliminate unwanted contributions and comparing results with other sum rule predictions.

Contribution

It introduces a novel method to remove unwanted transition contributions in light cone QCD sum rules for negative parity nucleon-pion coupling constants.

Findings

The negative parity nucleon-pion coupling constant differs significantly from 3-point QCD sum rule predictions.

The calculated coupling constant is close to the positive parity nucleon-pion coupling.

A new approach effectively isolates the desired transition contributions.

Abstract

We estimate strong coupling constant between the negative parity nucleons with $\pi$ meson within the light cone QCD sum rules. A method for eliminating the unwanted contributions coming from the nucleon--nucleon and nucleon--negative parity nucleon transition is presented. It is observed that the value strong coupling constant of the negative parity nucleon $N^\ast N^\ast \pi$ transition is considerably different from the one predicted by the 3--point QCD sum rules, but is quite close to the coupling constant of the positive parity $N N \pi$ transition.