Higher derivative terms in the πΔN interaction: Some phenomenological consequences

Abstract

In this paper we implement for the first time the use of a πN ∆(1232) vertex interaction containing both first and second order derivative terms, as required by renormalization considerations. As as was previously shown both interactions present formal problems, but can be implemented pertubatively. We put an end point to the discussion of which type of interaction is the apropriate one: both the usual pi-derivative and the "spin 3/2" gauge invariant that include also a derivative in the Delta field should be included in amplitude calculations. We show that when working within a tree level approach the description of total πN scattering in the different channels is improved.