The trigger system of the CHORUS experiment

A new apparatus for detection of nu(mu) --> nu(tau) oscillation has been successfully constructed and operated by the CHORUS Collaboration for the CERN-WA95 experiment. The design, implementation and performance of the electronic trigger system is described. A trigger efficiency of 99% was measured for nu(mu) charged-current events and 90% for neutral-current events

The trigger system of the CHORUS experiment

A new apparatus for detection of nu(mu) --> nu(tau) oscillation has been successfully constructed and operated by the CHORUS Collaboration for the CERN-WA95 experiment. The design, implementation and performance of the electronic trigger system is described. A trigger efficiency of 99% was measured for nu(mu) charged-current events and 90% for neutral-current events. (C) 1999 Elsevier Science B.V. All rights reserved. RI Ludovici, Lucio/F-5917-201

The data acquisition system of the CHORUS experiment

In the years 1994-1998 the CHORUS Collaboration has recorded data in the CERN WA95 experiment. Here we describe the data acquisition system that has been used, featuring concurrent hierarchical state machines, a remote operating system, a buffer manager, a dispatcher, a control panel and a supervisor. (C) 2002 Elsevier Science B.V. All rights reserved

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

Experimental study of trimuon events in neutrino charged-current interactions

This Letter reports on a study of trimuon events induced by neutrino interactions in the CHORUS calorimeter exposed to the CERN SPS wide-band v(mu) beam. Among the multimuon events produced in the calorimeter, 42 mu(-) mu(-) mu(+) events were selected and their kinematical properties investigated. In the past, several groups collected a sample of about one hundred events of this type but their source was largely unknown. Taking advantage of experimental data presently available on the production and muonic branching ratios of light neutral mesons and resonances, we make absolute predictions for the expected rates in our experiment. Detailed Monte Carlo simulations described in this article show that more than half of the trimuon events can be attributed to this source. Muons from pi- and K- decays in charm dimuon events are responsible for an additional approximate to 25% contribution to the total mu(-)mu(-)mu(+) rate. The remaining 25% of events are likely to come from the internal bremsstrahlung of virtual photons into a muon pair. Associated-charm production with subsequent decays of both charmed particles into muons is a negligible source of trimuon events. (C) 2004 Elsevier B.V. All rights reserved. RI Doucet, Mathieu/A-5333-2010; Ludovici, Lucio/F-5917-2011; De Rosa, Gianfranca/E-8737-2012; Fiorillo, Giuliana/A-2248-201

Measurement of the Z/A dependence of neutrino charged-current total cross-sections

A relative measurement of total cross-sections is reported for polyethylene, marble, iron, and lead targets for the inclusive charged-current reaction νμ + N → μ- + X. The targets, passive blocks of ∼ 100 kg each, were exposed simultaneously to the CERN SPS wide-band muon-neutrino beam over a period of 18 weeks. Systematic effects due to differences in the neutrino flux and detector efficiency for the different target locations were minimised by changing the position of the four targets on their support about every two weeks. The relative neutrino fluxes on the targets were monitored within the same experiment using charged-current interactions in the calorimeter positioned directly downstream of the four targets. From a fit to the Z/A dependence of the total cross-sections a value is deduced for the effective neutron-to-proton cross-section ratio.0SCOPUS: ar.jinfo:eu-repo/semantics/publishe

New results from a search for v(mu) -> v(tau) and v(e) -> v(tau) oscillation

A first analysis of the complete set of data collected by CHORUS in the years 1994-1997 is presented. The search for nu (tau) charged current events has been performed for both leptonic and hadronic decays of the tau lepton. No tau candidate has been found, A nu (tau) --> nu (tau) mixing is excluded down to sin(2)2 theta (mu tau) = 6.8 x 10(-4) for large Deltam(2) (90% C.L.)

New results from a search for v(mu) -> v(tau) and v(e) -> v(tau) oscillation

A first analysis of the complete set of data collected by CHORUS in the years 1994-1997 is presented. The search for nu (tau) charged current events has been performed for both leptonic and hadronic decays of the tau lepton. No tau candidate has been found, A nu (tau) --> nu (tau) mixing is excluded down to sin(2)2 theta (mu tau) = 6.8 x 10(-4) for large Deltam(2) (90% C.L.). (C) 2001 Elsevier Science B.V. All rights reserved

New results from a search for v(mu) -> v(tau) and v(e) -> v(tau) oscillation

A first analysis of the complete set of data collected by CHORUS in the years 1994-1997 is presented. The search for nu (tau) charged current events has been performed for both leptonic and hadronic decays of the tau lepton. No tau candidate has been found, A nu (tau) --> nu (tau) mixing is excluded down to sin(2)2 theta (mu tau) = 6.8 x 10(-4) for large Deltam(2) (90% C.L.)