The DONUT experiment has analyzed 203 neutrino interactions recorded in nuclear emulsion targets. A decay search has found evi-

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The OPERA neutrino experiment at the underground Gran Sasso Laboratory has measured the velocity of neutrinos from the CERN CNGS beam over a baseline of about 730 km. The measurement is based on data taken by OPERA in the years 2009, 2010 and 2011. Dedicated upgrades of the CNGS timing system and of the OPERA detector, as well as a high precision geodesy campaign for the measurement of the neutrino baseline, allowed reaching comparable systematic and statistical accuracies.An arrival time of CNGS muon neutrinos with respect to the one computed assuming the speed of light in vacuum of (6.5 ± 7.4 (stat.) +8.3 −8.0 (sys.)) ns was measured corresponding to a relative difference of the muon neutrino velocity with respect to the speed of light (v − c)/c = (2.7 ± 3.1 (stat.) +3.4 −3.3 (sys.)) × 10 −6 . The above result, obtained by comparing the time distributions of neutrino interactions and of protons hitting the CNGS target in 10.5 µs long extractions, was confirmed by a test performed at the end of 2011 using a short bunch beam allowing to measure the neutrino time of flight at the single interaction level.

review the design and construction of the detector and of its related infrastructures, and report on some technical performances of the various components. The construction of the detector started in 2003 and it was completed in Summer 2008. The experiment is presently in the data taking phase. The whole sequence of operations has proven to be successful, from triggering to brick selection, development, scanning and event analysis.

After completion of the data taking for the v(mu) -> v(tau) oscillation search, the CHORUS lead-scintillator calorimeter was used in the 1998 run as an active target. High-statistics samples of charged-current interactions were collected in the CERN SPS west area neutrino beam. This beam contained predominantly muon (anti-)neutrinos from sign-selected pious and kaons. We measure the flux and energy spectrum of the incident neutrinos and compare them with beam simulations. The neutrino-nucleon and anti-neutrino-nucleon differential cross-sections are measured in the range 0.01 < x < 0.7, 0.05 < y < 0.95, 10 < E-v < 200 GeV. We extract the neutrino-nucleon structure functions F-2(x, Q(2)), xF(3) (x, Q(2)), and R(x, Q2) and compare these with results from other experiments. (c) 2005 Elsevier B.V. All rights reserved

The DONuT experiment collected data in 1997 and published first results in 2000 based on four observed ντ charged-current (CC) interactions. The final analysis of the data collected in the experiment is presented in this paper, based on 3.6 × 10 17 protons on target using the 800 GeV Tevatron beam at Fermilab. The number of observed ντ CC interactions is 9, from a total of 578 observed neutrino interactions. We calculated the energy-independent part of the tau-neutrino CC cross section (ν +ν), relative to the well-known νe and νµ cross sections. The ratio σ(ντ )/σ(νe,µ) was found to be 1.37±0.35±0.77. The ντ CC cross section was found to be 0.72±0.24±0.36×10 −38 cm 2 GeV −1 . Both results are in agreement with expectations from the Standard Model.

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The OPERA experiment was designed to search for ν_{μ}→ν_{τ} oscillations in appearance mode, i.e., by detecting the τ leptons produced in charged current ν_{τ} interactions. The experiment took data from 2008 to 2012 in the CERN Neutrinos to Gran Sasso beam. The observation of the ν_{μ}→ν_{τ} appearance, achieved with four candidate events in a subsample of the data, was previously reported. In this Letter, a fifth ν_{τ} candidate event, found in an enlarged data sample, is described. Together with a further reduction of the expected background, the candidate events detected so far allow us to assess the discovery of ν_{μ}→ν_{τ} oscillations in appearance mode with a significance larger than 5σ.