J. Menes

Experimental study of the reactions K− +p → π− + Ω+ and K− +p → π− + Y∗ + (1385) at 8 and 16 GeV/c

Abstract Differential cross sections have been measured for K − + p → π − + Ω and K − + p → π − + Y ∗ + (1385) at 8 and 16 GeV/c and at small momentum transfer, using the missing mass spectrometer technique. The cross sections continue to be a factor of two higher than those for the corresponding associated production reactions obtained by line reversal, in disagreement with exchange degeneracy.

Search for the Z∗ in π− + p → K− + Z∗ at 6 and 8 GeV/c☆

Abstract We have looked for strangeness +1 baryons, Z ∗ s, in the reaction π − + p → K − + Z ∗ . Peaks at missing masses of about 1590 MeV and 1950 MeV are interpreted as reflections of boson decays and upper limits have been assigned for Z ∗ production.

Upper limits on rare two-body processes in K−−p and p̄−p scattering at high energies☆

Abstract A missing mass spectrometer search was made for several two-body, double charge exchange reactions, including backward K −p and pp elastic scattering at 8 and 16 GeV/ c and small momentum transfer. No examples of any of these processes were observed.

A large area high efficiency γ-ray detector with good time and space resolution☆

Abstract We describe the construction of a large area high efficiency γ detector for use in the 30 to 1000 MeV range. Its basic principle is the combination of lead-scintillator sandwich counters with optical spark chambers to achieve high γ efficiency along with good space and time resolution. The scintillator is arranged in the form of a hodoscope so that the spark chambers could be triggered on a selected number of simultaneous γ-rays. The performance in terms of γ efficiency, energy and direction resolution, and shower development are discussed.