Measurement of the total photon-photon cross section for the production of hadrons at small Q2

Abstract The total photon-photon cross section for the production of hadrons, σ γγ ( W , Q 2 ), has been measured in the single-tag condition for 0.1 Q 2 2 and 1.5 W Q 2 dependence of σ γγ average over W can be described by GVDM. The dependence of σ γγ on the mass W of the hadronic final state has been extracted at Q 2 = 0.44 GeV 2 by unfolding the effects of experimental resolution and acceptance. The cross section is found to rise at small W . The result is compared with VDM and the parton model.