Field theory of nucleon to higher-spin baryon transitions

Abstract

We discuss the nucleon to higher-spin $N$- and $Δ$-resonance transitions by pions and photons. The higher-spin baryons are described by Rarita-Schwinger fields and, as we argue, this imposes a stringent consistency requirement on the form of the couplings. Popular $πNΔ$ and $γNΔ$ couplings are inconsistent from this point of view. We construct examples of consistent interactions with the same nonrelativistic limit as the conventional ones.

5 pages, Revtex, 1 PostScript figure; published version