Investigation of the KSKLπ- system produced in π-p interactions at 40 GeV/c and observation of the decay mode a1→K bar K

The reaction π-p → KSKLπ-p is investigated by means of the 6-meter ITEP spectrometer irradiated by 40-GeV/c pions from the Serpukhov accelerator. The integrated flux incident on the target is 8 x 1010 pions. A partial-wave analysis of the KSKLπ- system is performed for statistics involving more than 8000 events. The number of required amplitudes is substantially reduced by detecting both KS and KL mesons. As the 1+ wave is found to be dominant and amenable to the parameter-free Toernqvist description, the conclusion is drawn that the K bar K system is dominated by the a1 meson at these energies. 17 refs., 8 figs