Peter Wanderer

A search for the vector boson (W particle), postulated as the mediator of the weak interaction, has been carried out by determining the intensity and polarization of muons originating very near the point of interaction of 28-GeV protons with nucleons. Bosons were not observed and the upper limit on the production cross section for W’s with masses between 2.0 and 4.5 geV/c² is B ˙ α_W ~ 6 × 10^-36 cm² where B is the branching ratio for the W decay to a muon and a neutrino. A comparison between the measured flux of muon pairs and the flux expected on the basis of a plausible model for the production and decay of both W’s and heavy virtual gammas suggests that the experiment may not have been sensitive to W’s, if they exist in this mass region.