T. J. Roberts

Neutron-nucleus inelastic cross sections from 160 to 375 GeV/c

Abstract We habe measured inelastic cross sections of neutrons on 14 nuclei ranging from hydrogen to uranium for neutron energies between 160 and 375 GeV. The measurements were made with a total absorption calorimeter and have an accuracy of 1%. The results are compared to other data and predictions of the Glauber model. Interaction lengths for high-energy neutrons in composite materials of practical interest are also given.

An inexpensive, high performance pulse-height readout system for proportional chambers

Abstract We describe a simple system to read out pulse-height information from a large number of proportional chambers. Its main features are simplicity, low noise, and wide dynamic range. A complete system with 6000 channels was built for less than

Neutron-proton differential cross sections in the range 70 to 400 GeV/c

7 per wire, including fabrication and cabling. Typical readout time is

Dimuon production by protons in Tungsten

Abstract We report the results of an experiment which measured np elastic scattering differential cross sections over a range in − t from 0.15 to ∼3.6 (GeV/ c ) 2 for incident neutron momenta from 70 to 400 GeV/ c . We find the logarithmic slope parameter, evaluated at − t = 0.2 (GeV/ c ) 2 , to be consistent with existing proton-proton parametrizations. The data exhibit a dip in the cross section near − t = 1.4 (GeV/ c ) 2 for incident neutron momenta above 200 GeV/ c . For neutron momenta less than 280 GeV/ c , the neutron-proton cross sections are found to be higher than existing proton-proton data in the range 0.7 ⩽ − t ⩽ 1.3 (GeV/ c ) 2 which is in contradiction to most Regge predictions.

RESULTS FROM A FERMILAB NEUTRINO BEAM DUMP EXPERIMENT

The mass spectrum of dimuons produced by 400 GeV/c protons in Tungsten has been measured for masses greater than 7 GeV. A clear resonant signal of 2700 upsilons has been seen. The dependence of dimuon production on xF and pT has been determined for dimuon masses in the range 7.0 to 8.25 GeV as well as for masses in the upsilon region 8.25 to 9.75 GeV.

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

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 Neutrino Results from Fermi Lab

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.

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

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.

A high‐statistics study of dimuon production by 400 GeV/c protons

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.

Mass and lifetime limits on supersymmetric particles from a proton beam-dump experiment

The reaction p+W→μ+μ−+X has been measured in a high‐statistics experiment using a 400 GeV/c proton beam, a magnetized beam dump, and a wide‐acceptance detector. Abbreviated results and a comparison with the Drell‐Yan Model are presented.