The TOSCA test beam

The two CERN experiments CHORUS and NOMAD are presently searching for neutrino oscillations in the Wide Band Neutrino Beam of the SPS. They are sensitive to small mixing angle s in the limit of large mass squared difference. In the case of a positive signal, the existence of neutrino oscillation will be inferred and a new higher sensitivity experiment will be needed to determine with precision the oscillation parameters. On the other hand, in the case of a negative search there are theoretical arguments in favour of an order of magnitude more sensitive exploration in the region of small mixing angles with a higher sensitivity to smaller mass differences.

Quite advanced simulations of possible detector configurations for the intended follow-up experiment TOSCA have been carried out so far and prototypes of the detector components are being designed and constructed. Soon a set of measurements with test beam s of pions will be taken in order to assess the intrinsic detector performance, to choose between different configurations and to "tune" the simulation of the full scale experiment. The basic test set-up will include an emulsion target placed in the field of a dipolar magnet, silicon strips, an emulsion tracker, a honeycomb tracker and MWPC's. Sets of beam defining counters and wire chambers will complete the set-up. The main aims of the test are:

  • The study of the precision of track extrapolation from the electronic trackers to the emulsion sheets in the presence of a magnetic field and the influence of the two track resolution;
  • The determination of the momentum resolution obtainable with different configurations of emulsion sheets and electronic trackers;
  • The determination of the precision in the track extrapolation from silicon strips to emulsion target;
  • The study of the event vertex location in the emulsion target in magnetic field, and the determination of the optimum emulsion target thickness;
  • The effect of the relative alignment of the different components on the overall detector performance.

    For more infomation click:


    Vanessa.Mexner@cern.ch , 25 September 1997