G. K. Fanourakis

Characteristics of a lead-scintillator calorimeter used to detect electron neutrinos

Abstract The response of a lead-liquid-scintillator calorimeter to electromagnetic and hadronic showers is reported. Operational characteristics, calibration, and the calculation of event energies are discussed. The hadronic resolution is measured to be 0.53 E ( GeV ) ; the electromagnetic resolution 0.27 E ( GeV ) . The charged current interactions of ν e have been identified by exploiting the difference in energy deposition along the beam direction for electron and hadron showers. The efficiency and effectivenes of the technique are discussed.

RESULTS FROM A FERMILAB NEUTRINO BEAM DUMP EXPERIMENT

The flux of prompt neutrinos from a beam dump has been measured in an experiment at the Fermi National Accelerator Laboratory (E613). Assuming that the charm production has a linear dependence on atomic number and varies as (1−‖×‖)5 e−2mT, a model dependent cross section of 27±5μb/nucleon can be derived. For neutrino energies greater than 20 GeV, the flux of electron neutrinos with respect to muon neutrinos is 0.78±0.19. For neutrinos with energy greater than 30 GeV and p⊥ greater than 0.2, the flux of νu compared to νμ is 0.96±0.22.

Prompt Production of Neutrinos By 400 GeV Protons on Tungsten: First Results from Fermilab E613

Data from Experiment E613, a Fermilab experiment to study prompt neutrino production, are now being analyzed. The experiment was specifically designed to study neutrinos from the decay of charmed (or other massive) particles. The detector, an 80 metric ton (fiducial volume) lead-scintillator calorimeter, is approximately 60 m from the target. As a result, the angular acceptance extends up to 40 mrad. We have run with a full density tungsten and 1/3 density tungsten target. We report on a sample of 938 neutrino 1μ events. If we parametrize the DD \( D\bar D \) production cross-section as proportional to (1-∣x∣)3 e-2p⊥ we find that our prompt neutrino 1μ events if interpreted as due to \( D\bar D \) production imply \( \sigma D\bar D \)17.2±3.2 (stat.) ±3.4 (sys) μb. For Ev greater than 25 GeV, the \( \bar \nu \) flux = \( \bar \nu \) flux =.8±.35 and the \( \bar \nu \) flux is 2.9σ from 0.

Prompt Neutrino Results from Fermi Lab

Results from a Fermi lab experiment to study prompt neutrino production are presented. Assuming the prompt neutrinos come from the decay of charmed mesons we find a total DD production cross section of approx. 20 μb/nucleon, in good agreement with previous CERN results. We find a ν/ν ratio and a νe/νμ of approx. 1.0. The energy and pT spectra of the prompt neutrinos are consistent with those expected from DD production. Limits on the production of supersymmetric particles have also been obtained.

The Relevance of the Fermilab Neutrino Beam Dump Experiment, E613, to Neutrino Oscillations

A beam dump experiment has been set up at Fermilab to study prompt neutrino production by 400 GeV protons. It is unusual among experiments seeking evidence for neutrino oscillations in that the neutrino path length is short, only 60 m, while the neutrino energies are high, 10 to 200 GeV. The experiment, expected to take data this spring, will be sensitive to oscillations ν e → ν x for values of ∆m2 between 200 and 10,000 (eV)2 and sin2 2α > 0.2.