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

We have observed highly virtual (Q2 > 1.05 GeV2) photon-photon collisions to hadronic final states at Se+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 < Wγγ < 25 GeV and Qγ,min2 >2 GeV region, while the lowest order quark-parton model predicted 3.00 pb.