Exclusive production of K⁺K⁻π⁺π⁻ in photon‐photon collisions Available to Purchase

We report a measurement of the reaction γγ→K⁺K⁻π⁺π⁻ in both tagged and untagged events at PEP. The cross section rises with invariant γγ mass to about 15 nb at 2 GeV and falls slowly at higher masses. We find clear evidence for the processes γγ→φπ⁺π⁻ and γγ→K^*0Kπ and we obtain upper limits (95% CL) of 1.5 and 5.7 nb in the mass range from 1.7 to 3.7 GeV for φρ⁰ and K^*0K̄^*0 production respectively.