Marta Luszczak

W + W − pair production in proton-proton collisions: small missing terms

A bstractW+W− production is one of the golden channels for testing the Standard Model as well for searches beyond the Standard Model. We discuss many new subleading processes for inclusive production of W+W− pairs generally not included in the literature so far. We focus on photon-photon induced processes. We include elastic-elastic, elastic-inelastic, inelastic-elastic and inelastic-inelastic contributions. We also calculate the contributions with resolved photons including the partonic substructure of the virtual photon. Predictions for the total cross section and differential distributions in W-boson rapidity and transverse momentum as well as WW invariant mass are presented. The γγ components constitute only about 1-2 % of the inclusive W+W− cross section but increases up to about 10 % at large W± transverse momenta, and are even comparable to the dominant qq¯

Single-diffractive production of charmed mesons at the LHC within the k t -factorization approach

q\overline{q}

c \bar c

component at large MWW, i.e. are much larger than the gg → W+W− one.

pairs in proton-proton collisions

We discuss production of nonphotonic electrons in proton-proton scattering at the relativistic heavy ion collider. The distributions in rapidity and transverse momentum of charm and bottom quarks/antiquarks are calculated in the k{sub t}-factorization approach. We use Kwiecinski unintegrated parton distributions and Ivanov-Nikolaev unintegrated gluon distribution. The hadronization of heavy quarks is done by means of Peterson and Braaten et al. fragmentation functions. The semileptonic decay functions are found by fitting recent semileptonic data obtained by the CLEO and BABAR collaborations. We get good description of the data at large transverse momenta of electrons and find a missing strength concentrated at small transverse momenta of electrons. Plausible missing mechanisms are discussed.

Production of charm quark/antiquark pairs at LHC

A bstractWe discuss the single-diffractive production of cc pairs and charmed mesons at the LHC. For a first time we propose a kt-factorization approach to the diffractive processes. The transverse momentum dependent diffractive parton distributions are obtained from standard (collinear) diffractive parton distributions used in the literature. In this calculation the transverse momentum of the pomeron is neglected with respect to transverse momentum of partons entering the hard process. We also perform a first evaluation of the cross sections at the LHC using the diffractive transverse momentum dependent parton distributions. The results of the new approach are compared with those of the standard collinear one. Significantly larger cross sections are obtained in the kt-factorization approach in which some parts of higher-order effects is effectively included. The differences between corresponding differential distributions are discussed. Finally, we present a feasibility study of the process at the LHC using proton tagging technique. The analysis suggests that the measurement of single-diffractive charm production is possible using ATLAS and CMS/TOTEM detectors.

Subleading processes in production of W + W − pairs in proton-proton collisions

At high-energies the gluon-gluon fusion is the dominant mechanism of

Open charm meson production at LHC

c \bar c

Single-diffractive production of dijets within the

production. This process was calculated in the NLO collinear as well as in the k