2nd Class Currents in Neutrino Reactions

Abstract

AbstractThe influence of 2nd class currents in neutrino reactions is investigated. We show that WEINBERG'S unified model of electromagnetic and weak interactions implies both neutral and 2nd class currents. Possible experimental effects due to 2nd class neutral weak currents are discussed. Further, we investigate implications of 2nd class charged currents for hadronic neutral weak currents. It is shown that if 2nd class charged currents exist, the isospin I = 1 axial‐vector neutral current must be a “new” current, or it must contain a “new” I = 1 part. 2nd class charged currents are excluded if the I = 1 axial‐vector neutral current is “old”, i.e., if it is proportional to the third component of the charged current. Then also the proportionality constant is real. CP invariance is assumed throughout the discussion.