G. Mancarella

A new design scintillating fiber calorimeter to search for neutrino oscillations in massive underground detectors

Abstract A new design for an electromagnetic and hadronic calorimeter using the scintillating fiber technology is presented. The proposed calorimeter has been optimized for applications in massive underground experiments devoted to neutrino oscillation studies. The layout is described in detail and first results on a prototype are presented. Finally, simulations showing the features of the whole calorimeter are discussed.

Effects of nuclear re-interactions in quasi-elastic neutrino–nucleus scattering

Abstract The effects of nuclear re-interactions in the quasi-elastic neutrino–nucleus scattering are investigated with a phenomenological model. We found that the nuclear responses are lowered and that their maxima are shifted towards higher excitation energies. This is reflected on the total ν-nucleus cross-section in a general reduction of about 15% for neutrino energies above 300 MeV.

The NOE scintillating fiber calorimeter prototype test results

Abstract An intense R&D program has been carried out by the NOE Collaboration during the last years, to develop a massive fine grain scintillating fiber calorimeter, to be used, in combination with an appropriate target, in a Long Base Line experiment at the CERN to Gran Sasso (CNGS) neutrino beam. The performance of a 4 ton NOE calorimeter prototype exposed to a test beam at CERN PS is shown. Results on the linearity, electromagnetic and hadronic energy resolution are reported and compared with the Monte Carlo predictions.

A transition radiation detector interleaved with low-density targets for the NOE experiment

Abstract The NOE Collaboration has proposed a transition radiation detector (TRD) interleaved with marble targets to tag the electron decay channel of τ leptons produced by ν τ , eventually originated by ν μ oscillations in a long base line experiment. A reduced scale TRD detector prototype has been built and exposed to an electron/pion beam at the CERN PS. Discrimination capabilities between electrons and both charged and neutral pions, representing the main source of background for our measurement, have been determined obtaining rejection factors of the order of the tenth of percent for charged pions, and of a few percent for the neutral pion, matching the experiment requirements. The capabilities of this detector to measure the energy released by particles that start showering inside the targets are shown. A momentum resolution σ p / p ≤40% is found for muons in the range of 1– 7 GeV /c .

Magnetic monopole trigger with streamer tubes in the MACRO experiment at Gran Sasso

Abstract We illustrate the performances of the trigger system for the search of cosmic magnetic monopoles, with the streamer tubes of MACRO, for β ≥ 10−4.

Evaluation of candidate photomultiplier tubes for the NOE scintillating fiber calorimeter

Several measurements have been made on different phototubes in order to select the type to be used for the readout system of the NOE magnetized scintillating fiber calorimeter. Characteristics such as gain, linearity, time resolution and cathode uniformity have been examined on several PMT types with standard, fine mesh or channel multiplier structure. The PMT response in the presence of the magnetized calorimeter fringe fields has also been studied. Here we report on the results of these measurements and of the comparisons between the different PMT types.

Wavelength-shifting fibers for calorimetric measurements in a long base line neutrino oscillation experiment

Abstract The NOE Collaboration has proposed a calorimeter to measure the energy of the final states of ν interaction events. The properties of long scintillator bars with wavelength-shifting fiber readout have been studied to develop a calorimeter design option. Various prototypes have been exposed to a cosmic rays stand. The total measured light yield in the middle of a 6 m -long fiber is about 15 photoelectrons. With this photon collection performance, it has been simulated that the calorimeter can achieve 17%/ E and 50%/ E resolutions for electrons and pions, respectively.

Performance of a magnetized calorimeter for a long baseline neutrino oscillation experiment

Abstract In this paper we present a study of the momentum measurement ability of the magnetized calorimeter proposed for the ICANOE experiment. For the calorimeter tracker we have designed a system based on aluminum drift tubes 8.5 m long and with a square inner cross-section of 2.6×2.6 cm 2 , fed by an Ar–CO 2 gas mixture. Magnetic field measurements performed on reduced scale prototypes show that an average magnetic flux density of ∼1.3 T can be achieved. From tests with cosmic rays and beam particles, we also show that the drift tubes used for the tracker allow to obtain spatial resolutions better than 400 μm . The muon momentum resolution achievable with the proposed layout is ∼30%.