Factorization scheme analysis of $F_2^{\gamma}(x,Q^2)$ and parton distributions functions of the photon
Abstract
Factorization scheme analysis of $F_2^{\gamma}(x,Q^2)$ in the nexttoleading order QCD is revisited. It is emphasized that the presence of the inhomogeneous term in the evolution equations for quark distribution functions of the photon implies subtle but important difference in the way factorization mechanism works in photonhadron and photonphoton collisions as compared to the hadronic ones. It is argued that none of the existing NLO analyses of $F_2^{\gamma}(x,Q^2)$ takes this difference properly into account. The source of the ensuing incompleteness is traced back to the misinterpretation of the behaviour of $q^{\gamma}(x,M)$ as a function of $\alpha_s(M)$. Parton model interpretation of the so called ``constant terms'' in the LO photonic coefficient function $C_{\gamma}^{(0)}(x)$ is given and smooth transition between the properties of virtual and real photon analyzed. Finally phenomenological consequences of this analysis are discussed.
 Publication:

arXiv eprints
 Pub Date:
 November 1998
 DOI:
 10.48550/arXiv.hepph/9811455
 arXiv:
 arXiv:hepph/9811455
 Bibcode:
 1998hep.ph...11455C
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
 20 pages, Latex, 5 figures in EPS format attached