Coherent single pion production by antineutrino charged current interactions and test of PCAC
Zeitschrift für Physik C Particles and Fields 31:2 (1986) 191-197
Abstract:
The cross section for coherent production of a single π- meson in charged current antineutrino interactions on neon nuclei has been measured in BEBC to be (175±25) 10-40 cm2/neon nucleus, averaged over the energy spectrum of the antineutrino wide band beam at the CERN SPS; this corresponds to (0.9±0.1) % of the total charged current {Mathematical expression} cross section. The distributions of kinematical variables are in agreement with theoretical predictions based on the PCAC hypothesis and the meson dominance model; in particular, the Q2 dependence is well described by a propagator containing a mass m=(1.35±0.18) GeV. The absolute value of the cross section is also in agreement with the model. This analysis thus provides a test of the PCAC hypothesis in the antineutrino energy range 5-150 GeV. © 1986 Springer-Verlag.Evidence for higher twist effects in fast π- production by antineutrinos in neon
Zeitschrift für Physik C Particles and Fields 31:1 (1986) 51-58
Abstract:
Evidence for a significant higher twist contribution to high z π- production in antineutrino scattering is presented. In events with W>3 GeV and Q2>1 GeV2 in our data, it accounts for (51 ±8)% of all π- with z above 0.5. It is consistent with the z-Q2 correlations of Berger's higher twist prediction. The data are inconclusive concerning the predicted y-z correlation and pT dependence. The z -Q2 correlation is not adequately described by the Lund Monte-Carlo. © 1986 Springer-Verlag.Bounds on light gluinos from the BEBC beam dump experiment
Physics Letters B 160:1-3 (1985) 212-216
Abstract:
Observational upper limits on anomalous neutral-current events in a proton beam dump experiment are used to constrain the possible hadroproduction and decay of light gluinos. These results require ifmg̃ $ ̌4 GeV for ifmq̃ - minw. © 1985.Search for heavy neutrino decays in the BEBC beam dump experiment
Physics Letters B 160:1-3 (1985) 207-211
Abstract:
New limits on lepton mixing parameters are derived from a search for decays of heavy neutrinos in a proton beam dump experiment. The limits |Uøi|2, |Uei|2 < 10-6-10-7 are obtained for neutrino mass eigenstates vi of mass between 0.5 and 1.75 GeV, which can be produced through mixing in charmed D meson decays. This is the first such limit on |Uøi|2 for neutrino masses greater than 0.5 GeV. For the mass eigenstate v3 in particular, we obtain the limits |Uø3|2 < 10-7-10-8, |Ue3|2 < 10-9-10-10 for the mass range 150-190 MeV, assuming the v3 to be produced directly in charmed F meson decays. © 1985.Dilepton and trilepton production by antineutrinos and neutrinos in neon
Zeitschrift für Physik C Particles and Fields 29:1 (1985) 15-28