K + mesons stopped in C3F8 in the Lawrence Radiation Laboratory (LRL) 30-inch heavy liquid bubble chamber were used in a study of the properties of the decay mode K+ -> ir 0 -\-jx + +v. The properties studied were the /*+ and ir° energy spectra, fx + longitudinal polarization, ju + total polarization, and K^+/K e9 + branching ratio. The data are consistent with the universal V-A theory, with time-reversal invariance, and fx-e universality. Using the usual form-factor phenomenological expression for the strangeness-changing vector current, we obtain:Re £= +0.34_o.26 +0 -42 , Im £= +0.69_i. 0 -H) -86 , X + =0.00±0.05, f+(£"•)//+(£.«) = 1.01±0.05. Im £ should vanish by time-reversal invariance and/ + (iC M 3)//+(i£e3) should be unity if n-e universality holds. With these assumptions we obtain Re £==0.41_o.22 +0 -27 . CALLAHANet at.

The magnitude of the KS°~KL° mass difference Aw has been measured by monitoring the time dependence of the strangeness of neutral iTs produced in hydrogen and deuterium in the LRL 25-in. hydrogen bubble chamber. The particles originate as K° in Kr charge-exchange scatters at 0.85 to 1.15 BeV/c; the signature for an S--1 reaction is the production of a hyperon. Seventy-seven events were found, resulting in Ao> =0.50±0.15, measured in units of inverse Ks° lifetime. This and two other recent measurements using the same method are consistent with one another and with measurements of Aoo by other means.