Observation of highly virtual photon-photon collisions to hadrons at TRISTAN

Abstract We have observed highly virtual ( Q 2 > 1.05 GeV 2 ) photon-photon collisions to hadronic final states at S e+e− = 58 GeV . The integrated luminosity of the data sample was 241 pb −1 . Both scattered beam-electrons and scattered beam-positrons were detected using low-angle calorimeters (i.e., both photons were highly virtual, “ouble-tag”); we obtained 115 hadronic events with an estimated background of 10.2 ± 1.1. The cross section obtained was 4.11 ± 0.66 pb in the 2 W γγ Q γ,min 2 >2 GeV region, while the lowest order quark-parton model predicted 3.00 pb.