Anna Cisek

Exclusive photoproduction of charmonia in γp → V p and pp → pV p reactions within k t -factorization approach

A bstractThe amplitude for γp → J/ψp (γp → ψ′p) is calculated in a pQCD kT -factorization approach. The total cross section for this process is calculated for different unintegrated gluon distributions and compared with the HERA data and the data extracted recently by the LHCb collaboration. The amplitude for γp → J/ψp (γp → ψ′p) is used to predict the cross section for exclusive photoproduction of J/ψ (ψ′) mesons in proton-proton collisions. Compared to earlier calculations we include both Dirac and Pauli electromagnetic form factors. The effect of the Pauli form factor is quantified. We discuss the role of the J/ψ and ψ′cc¯

The γγ → J/ψJ/ψ reaction and the J/ψJ/ψ pair production in exclusive ultraperipheral ultrarelativistic heavy ion collisions

c\overline{c}

\omega

wave functions for differential distributions and corresponding ratios for ψ′ and J/ψ. Absorption effects are taken into account and their role is discussed in detail. Different differential distributions e.g. in J/ψ (ψ′) rapidity and transverse momentum are presented and compared with existing experimental data. The unintegrated gluon distribution with nonlinear effects built in and Gaussian wave functions better describe recent experimental data of the LHCb collaboration but no definite conclusion on onset of saturation can be drawn. We present our results also for the Tevatron. A good agreement with the CDF experimental data points at the midrapidity for both J/ψ and ψ′ is achieved.

meson in proton-proton collisions at high energies

We extend the k{sub perpendicular}-factorization formalism for exclusive photoproduction of vector mesons to the production of electroweak Z{sup 0} bosons. Predictions for the {gamma}p{yields}Z{sup 0}p and pp{yields}ppZ{sup 0} reactions are given using an unintegrated gluon distribution tested against deep inelastic data. We show distributions in the Z{sup 0} rapidity, transverse momentum of Z{sup 0} as well as in relative azimuthal angle between outgoing protons. The contributions of different flavors are discussed. Absorption effects lower the cross section by a factor of 1.5-2, depending on the Z-boson rapidity. We also discuss the production of Z{sup 0} bosons in central inclusive production. Here rapidity and (x{sub IP,1},x{sub IP,2}) distributions of Z{sup 0} are calculated. The corresponding cross section is about 3 orders of magnitude larger than that for the purely exclusive process.

Exclusive photoproduction of ϕ meson in γp→ϕp and pp→pϕp reactions

We calculate the cross section for the γγ→J/ψJ/ψ process. Two mechanisms are considered: box (two-loop) diagrams of the order of

Some New Aspects of Quarkonia Production at the LHC

O(\alpha_{\mathrm{em}}^{2} \alpha_{s}^{2})

Exclusive photoproduction of

and two-gluon exchange of the order of

\phi

O(\alpha_{\mathrm{em}}^{2} \alpha_{s}^{4})