Experimental Test of Baryon Conservation and Neutrino Flux Limits

An experiment has been performed in which events not directly attributable to cosmic rays or natural radioactivity were observed for 4500 h in a 200-liter liquid scintillation detector. Shielding from cosmic rays was obtained through anticoincidence techniques and by locating the detector 585 m underground. Background from natural radioactivity was reduced by placing high-energy requirements on acceptable events. The residual signal has been used to establish new lower limits on the stability of nucleons and a new upper limit on the product of the cross section and the electron neutrino (₄, {}₄) flux whatever its origin, providing its energy is 400 MeV and >30 MeV (₄) or > 12 MeV ({}₄). Depending on the assumed decay modes, nucleon lifetime limits in the range 0. 610^28 to 410^28 years were obtained. The upper limits on the neutrino cross-section flux products are 8. 510^-38₄ sec^-1 and 3. 210^-38{}₄ sec^-1.