The reactions K/sup -/p to lambda pi /sup 0/, Lambda eta , Lambda eta ' at 42 GeV/c

In a high statistics CERN 2 m bubble chamber experiment the different cross sections and polarizations of the Lambda for the reactions K/sup -/p to Lambda pi /sup 0/, Lambda eta , lambda eta ' at 4.2 GeV/c have been measured. The reaction K/sup -/p to Lambda eta exhibits a pronounced dip around -t approximately 0.5 (GeV/c)/sup 2/ and all three reactions show a significant backward peaking (-u<1.0 (GeV/c) /sup 2/). The Lambda polarization in the reaction K/sup -/p to Lambda pi /sup 0/ is measured to be significantly different from zero throughout most of the available t-range. Forward cross sections enable a determination of R/sub T/, the ratio of singlet/octet coupling eta /sub 1/KK**/ eta /sub 8/KK**. Backward cross sections are utilized to estimate the effective eta -nucleon coupling constant g /sub eta NN//sup 2/ over the -u range 0-1.5 (GeV/c)/sup 2/. (14 refs).