Partial wave analysis of backwardly produced three pion systems in K-p interactions at 4.2 GeV/c

The results of a partial wave analysis of the 3π system produced by baryon exchange in the reaction K-p → Σ- π+π+π-. at 4.2 GeV/c is reported. The existence is confirmed of an enhancement in the 1+S(rhoπ) wave at a mass = 1040 +- 13 MeV and with a width = 230 +- 50 MeV as previously established from a Dalitz plot analysis of the same data. The phase variation of this wave is found to be consistent with that expected for a resonance and thus the enhancement is identified with A1 production. No clear signal for this state is found in either the reaction K-p → Σ+ π+π-π-or K-p → Λ π+π-π0. Production via baryon exchange of the A2 in all three reactions and the ω and ω* (1675) in the third reaction was found. (author)