The Parton Structure of Real Photons
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چکیده
The QCD treatment of the photon structure is recalled. Emphasis is given to the recently derived momentum sum rule, and to the proper choice of the factorization scheme and/or boundary conditions for the evolution equations beyond the leading order. Parametrizations of the photon’s parton content are examined and compared. The small-x behaviour of the photon structure is briefly discussed. ∗ Invited talk presented at Photon ’97, Egmond aan Zee, The Netherlands, May 1997. To appear in the proceedings. THE PARTON STRUCTURE OF REAL PHOTONS ANDREAS VOGT Institut für Theoretische Physik, Universität Würzburg, Am Hubland, D–97074 Würzburg, Germany The QCD treatment of the photon structure is recalled. Emphasis is given to the recently derived momentum sum rule, and to the proper choice of the factorization scheme and/or the boundary conditions for the evolution equations beyond the leading order. Parametrizations of the photon’s parton content are examined and compared. The small-x behaviour of the photon structure is briefly discussed.
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تاریخ انتشار 1997