Marta Łuszczak

Production of twocc¯pairs in double-parton scattering

We discuss production of two pairs of

Two-photon dilepton production in proton-proton collisions: Two alternative approaches

c \bar c

Single- and central-diffractive production of open charm and bottom mesons at the LHC: theoretical predictions and experimental capabilities

within a simple formalism of double-parton scattering (DPS). Surprisingly very large cross sections, comparable to single-parton scattering (SPS) contribution, are predicted for LHC energies. Both total inclusive cross section as a function of energy and differential distributions for

Inclusive production of Higgs boson in the two-photon channel at the LHC within

\sqrt{s}

k_{t}

are shown. We discuss a perspective how to identify the double scattering contribution.

-factorization approach and with the Standard Model couplings

We investigate different methods to incorporate the effect of photons in hard processes. We compare the two different approaches used for calculating cross sections for the two-photon

Open charm meson production at BNL RHIC within

pp\ensuremath{\rightarrow}{l}^{+}{l}^{\ensuremath{-}}X

k_{t}

process. In one of the approaches the photon is treated as a collinear parton in the proton. In the second approach the recently proposed

-factorization approach and revision of their semileptonic decays

{k}_{T}

Diffractive dissociation of gluons into heavy quark–antiquark pairs in proton–proton collisions

factorization method is used. We discuss how results of the collinear parton model depend on the initial condition for the QCD evolution and discuss an approximate treatment where the photon is excluded from the combined QCD-QED evolution. We demonstrate that it is not necessary to put the photon into the evolution equation as is often done, but it is sufficient to use a simplified approach in which the photon couples to quarks and antiquarks, which by themselves undergo DGLAP evolution equations. We discuss the sensitivity of the results to the choice of structure function parametrization and experimental cuts in the