Radiatively generated parton distributions of real and virtual photons
Radiatively generated parton distributions of real and virtual photons
The parton content of real ${(P}^{2}=0)$ and virtual ${(P}^{2}\ensuremath{\ne}0)$ transverse photons $\ensuremath{\gamma}{(P}^{2})$ is expressed in terms of perturbative pointlike and nonperturbative hadronic (VMD) components, employing recently updated parton distributions of pions and protons. The resulting parameter-free and perturbatively stable LO and NLO parton densities ${f}^{\ensuremath{\gamma}{(P}^{2})}{(x,Q}^{2})$ are smooth in ${P}^{2}$ and …