Electron Neutrino Oscillations Research Articles

The search for inclusive electron-neutrino oscillations on the Serpukhov 70 GeV accelerator with the IHEP-JINR neutrino detector

The experiment on the search for inclusive electron neutrino oscillations is being carried out at the special neutrino beam of the Serpukhov 70 GeV accelerator using the IHEP-JINR neutrino detector. The short decay cavity of the neutrino beam makes it possible to search for oscillations analyzing the shape of the distribution of events using the variable L E , where L is the distance from the point of origin to the point of interaction of neutrino, E is the neutrino energy. The data of the two runs are processed and analysed. The best fit is obtained with Δm 2 = 300 eV 2 and sin 2 2Θ = 0.144, but the X 2 does not differ much for the hypothesis of no oscillations (within one standard deviation). This gives the limits on the oscillation parameters of sin 2 2Θ < 0.115 at Δm 2 = 175 eV 2 (90% C.L.). For reasons outlined in the text, we believe this limit to be better or more reliable than earlier limits published by other experiments.

Limits on electron-neutrino oscillations from the GALLEX 51Cr source experiment

The recent result from the chromium source experiment carried out by the GALLEX collaboration implies interesting limits on the parameters Δm 2 and sin 2 2 θ describing neutrino oscillations. Values of Δm 2 > 0.17 eV 2 for maximal mixing and of sin 2 2 θ > 0.38 for Δm 2 > 1 eV 2 are ruled out at 90% C.L. This result improves by more than an order of magnitude previous limits on Δm 2 derived from electron-neutrino oscillation experiments at accelerators.