Measurement of the total hadronic cross section in virtual photon-photon interactions

Abstract

The total hadronic cross section for virtual photon-photon interactions is reported for center-ofmass energy, W, between 2 and 20 GeV. The data were obtained via the process e + e~ -e + e~y*y*~• e + e~ + hadrons with both scattered e + and e~ detected. Each photon's fourmomentum squared, a 1 , ranges from -0.1 to -1.6 GeV 2 . Dependence upon q 2 agrees with a generalized vector-meson-dominance model. The total cross section shows little W dependence, averaging 125 nb at q 2 = ql = -0.3. Photon helicity interference terms are determined.

The photon structure from deep inelastic electron–photon scattering

“…The data used in the fits are from Refs. [83,96,67,68,97,98,69,70,99,100,72]. The structure function F γ 2 obtained from the LAC parametrisations is shown in Figure 23 for two typical values of Q 2 where data are available from the LEP experiments, Q 2 = 5 and 135 GeV 2 .…”

“…The data used in the fits are published data from Refs. [83,67,98,68,97,69,70,99,100,72] and preliminary data from Refs. [96], all subject to the additional requirement W > 2 GeV mentioned above.…”

“…The data used in the fits are published data from Refs. [83,84,111,67,112,103,68,69,109,70,110,99,72,71] and preliminary data from Refs. [96,104,113].…”

Hadronic photon-photon interactions at high energies

“…With these possibilities phojet should be a tool suitable to study the photon-photon background to other interesting reactions at such colliders. Weight (µb) 0.0032 Figure 1: Inelastic photon-photon cross sections as calculated in the model compared with experimental data at low energies [48,49,50,51,52]. The two curves from the model were calculated using the GRV LO photon structure function [17] and the SaS 2M photon structure function [53].…”

“…Inelastic photon-photon cross sections as calculated in the model compared with experimental data at low energies48,49,50,51,52]. The two curves from the model were calculated using the GRV LO photon structure function 17] and the SaS 2M photon structure function 53].…”