Systematic effects in the determination of the πNN coupling from differential cross section

Abstract

We show that the πN N coupling constant extracted model-independently frompp charge exchange is subject to a systematic correction, and, more importantly, that the strong absorption in the critical region prevents a determination of the coupling constant to high precision using this process. This attenuates the possible conflict with the value determined from the np charge exchange cross sections.The value of the πNN coupling constant has become a topic of hot debate in the last few years [1]. In addition from the 'classical' determinations from πN scattering and forward NN dispersion relations with a 'high' value of g 2 near 14.3, the Nijmegen group has argued a lower value of about 13.6 on the

Goldberger-Treiman constraint criterion for hyperon coupling constants

“…2 and 3 we compare all tabulated Λ and Σ couplings, respectively, in histogram form and also indicate the broken SU F (3) interval (dark gray), GT (diamond) and Taylor series (inverted triangle) couplings. Applying the constraint criterion, the intercept b requires specifying g πN N which is still subject to discussion [11,34,35,36,37,38,39]. Nevertheless, it is generally accepted that 12.90 ≤ g πN N ≤ 13.20.…”