Measurement of D production in two-photon processes at TRISTAN AMY Collaboration

The inclusive cross section for the production of charmed D mesons in twophoton processes is measured with the AMY detector at the TRISTAN e + e collider. D mesons are identi ed from the distribution of charged-particle transverse momenta relative to the jet axis. A data sample corresponding to an integrated luminosity of 176 pb 1 at a center-of-mass energy of 58 GeV is used to determine a cross section (e + e ! e + e D X) = 270 49(stat) 38(syst) pb. The results are compared with theoretical expectations based on the Vector Meson Dominance, direct quark-parton model, and resolved photon processes.