Observation of weak neutral current neutrino production of J/ψJ/\psi

Observation of \jpsi production by neutrinos in the calorimeter of the CHORUS detector exposed to the CERN SPS wide-band \numu beam is reported. A spectrum-averaged cross-section $\sigma^{\mathrm{J/\psi}}$ = (6.3 $\pm$ 3.0) $\times \mathrm{10^{-41}~cm^{2}}$ is obtained for 20 GeV $\leq E_{\nu} \leq$ 200 GeV. The data are compared with the theoretical model based on the QCD Z-gluon fusion mechanism

Observation of weak neutral current neutrino production of J/ψJ/\psi

Observation of \jpsi production by neutrinos in the calorimeter of the CHORUS detector exposed to the CERN SPS wide-band \numu beam is reported. A spectrum-averaged cross-section $\sigma^{\mathrm{J/\psi}}$ = (6.3 $\pm$ 3.0) $\times \mathrm{10^{-41}~cm^{2}}$ is obtained for 20 GeV $\leq E_{\nu} \leq$ 200 GeV. The data are compared with the theoretical model based on the QCD Z-gluon fusion mechanism

Performance of the CHORUS Calorimeter With Neutrino Events

Lisbon, Portuga

Performance of the CHORUS Calorimeter with neutrino events

The CHORUS calorimeter is a large scale application of the lead-scintillating fibre calorimetry technique for high energy physics experiments. It uses 1450 km of fibres for a total calorimeter weight of 110 tons. We report here about the time stability of the scintillating fibres performances over five years of data taking in the CERN-WANF neutrino beam. The identification capability of particles produced in neutrino interactions is discussed. The identification algorithm is based on a neural network approach

New results from a search for νμ→ντ\nu_{\mu} \to \nu_{\tau} and νe→ντ\nu_{e} \to \nu_{\tau} oscillation

A first analysis of the complete set of data collected by CHORUS in the years 1994-1997 is presented. The search for \nut charged current events has been performed for both leptonic and hadronic decays of the \tauu lepton. No \tauu candidate has been found. A \numtonut mixing is excluded down to $\sin2t$ = $6.8 \times 10^{-4}$ for large \dm2 (90\%~C.L.)

New results from a search for νμ→ντ\nu_{\mu} \to \nu_{\tau} and νe→ντ\nu_{e} \to \nu_{\tau} oscillation

A first analysis of the complete set of data collected by CHORUS in the years 1994-1997 is presented. The search for \nut charged current events has been performed for both leptonic and hadronic decays of the \tauu lepton. No \tauu candidate has been found. A \numtonut mixing is excluded down to $\sin2t$ = $6.8 \times 10^{-4}$ for large \dm2 (90\%~C.L.)