Effective QCD coupling and power corrections to photon-photon scattering
نویسنده
چکیده
The scattering of two off-shell photons is an infrared-safe process in QCD. For photon virtualities Q in the range of a few GeV, accessible at LEPII, powerbehaved contributions in (ΛQCD/Q) n to the total cross section may become non-negligible. Based on a dispersion relation for the running coupling, we discuss these contributions and calculate the coefficients of the leading power correction for transversely polarized and longitudinally polarized virtual photons. Typeset using REVTEX
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