STUDY OF Kn SCATTERING USING THE REACTIONS

An elastic Kn partial wave analysis is presented. It is based on high statistics data for the reactions K*p K*r’n and K*p K*nA* at 13 GeV obtained in a spectrometer experiment performed at SLAC. For each reaction, a t-dependent parametrization of the production amplitudes provides information on both the Kr mass dependence of the production mechanisms and on Kn scattering. Knowledge of the t-dependence then allows a calculation of the K7r partial wave amplitudes for Kn masses from 0.7 to 1.9 GeV. The results of such analyses using data for (i) the neutron recoil reactions, (ii) the A* -iirecoil reactions, and (iii) both neutron and A recoil reactions simultaneously are presented. Besides the leading Jp=l-, 2’, and 3resonances at MKr=. 896, 1..434, and 1.78 GeV, there is evidence in two of the four possible partial wave solutions for a broad P-wave resonant-like structure in the region of 1700 MeV. The 1=1/2 S-wave magnitude rises slowly and smoothly to a maximum near 1400 MeV, but then decreases rapidly between 1400 and 1600 MeV. This structure is strongly indicative of an S-wave resonance near 1450 MeV. The charge two K7r reaction is dominated by S-wave scattering with a total cross section decreasing from 4 mb at 0.9 GeV to 2 mb at 1.5 GeV. Both the 1=1/2 S-wave below 1400 MeV and the 1=3/2 S-wave are well described by an effective range parametrization.