Abstract:

Data on the charge-exchange reaction π-p → (π+π-π0)n have been taken at beam momenta of 12 and 15 GeV/c, using the CERN Omega Multiparticle Spectrometer. A partial-wave analysis has been made of the (3π)0 system. We observe both natural and unnatural spin-parity production. The natural parity states can be identified with established resonances. In addition a natural spin-parity enhancement is observed at a mass of about 2 GeV/c2 with JP = 4+ preferred. We have called this effect the A2* (2030). The unnatural spin-parity production found is consistent with reggeized Deck model predictions. No unambiguous A1 or A3 production is observed. © 1978.

Abstract:

We have observed the D(1285), E(1420) and δ(975) mesons produced in 12 and 15 GeV/c π-p interactions at the CERN Omega Spectrometer. Production cross sections and decay branching ratios are presented. Analysis of the decay D(1285) → δ(975) π favours a spin-parity assignment of 1+. © 1978.

Abstract:

The production of the f0 (1270) has been studied in the reaction π-p → π+π-n at 12 and 15 GeV/c in the momentum transfer range 0.02 to 0.80 GeV2. Differential and total cross sections for the reaction π-p → f0n have been determined. The f0 decay density matrix elements have been evaluated requiring all the matrix eigenvalues to be non-negative. The relative unnatural and natural parity exchange contributions to the f0 production have been studied. The results are compared with a Regge exchange model formulated in terms of the pion and A2 exchanges including cut contributions. © 1977.