Investigation of Matter Enhanced Neutrino Oscillations Relevant to the Solar Neutrino Problem

Abstract We study the effect of matter enhanced neutrino oscillations on atmospheric neutrinos. A recently proposed solution to the solar neutrino problem with Δm 2 = 1.1×10 −4 eV 2 suggests enhanced effects in the range 200 MeV-500MeV. We find no evidence of this effect for v μ ↔ v e mixing. Limits are set on the magnitude of the mixing angle. Our limit is sin θ v