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The production of large pT dileptons and photons originating from photoproduction processes in p-p collisions at Large Hadron Collider energies is calculated. The comparisons between the exact treatment results and the ones of the equivalent photon approximation approach are expressed as the Q 2 (the virtuality of photon) and pT distributions. The method developed by Martin and Ryskin is used for avoiding double counting when the coherent and incoherent contributions are considered simultaneously. The numerical results indicate that, the equivalent photon approximation is only effective in small Q 2 region and can be used for coherent photoproduction processes with proper choice of Q 2 max ( the choices Q 2 max ∼ŝ or ∞ will cause obvious errors), but can not be used for incoherent photoproduction processes. The exact treatment is needed to deal accurately with the photoproduction of large pT dileptons and photons.

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We study the quark Wigner distributions of the pion meson which are the phase-space distributions containing the most general one-parton information. Using the pion wavefunctions deduced from a light-cone quark model, we calculate the Wigner distributions of the unpolarized, longitudinally polarized and transversely polarized quarks inside the pion meson via the Fock-state overlap representation, respectively. We present the numerical results of the transverse Wigner distributions in which the longitudinal momentum fraction is integrated out. The mixed Wigner distributions as functions of by and kx are also presented. As a intermediate step, we provide the analytic results for the generalized transverse momentum dependent distributions of the pion meson in the same model.

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