Our calculation of the total cross section for inclusive production of tt̄ pairs in hadron collisions is presented. The principal ingredient of the calculation is resummation of the universal leading-logarithm effects of gluon radiation to all orders in the quantum chromodynamics coupling strength, restricted to the region of phase space that is demonstrably perturbative. We derive the perturbat...

It was predicted by Watson and Migdal [1] that close to threshold the energy dependence of the cross section is dominated by the Final State Interaction (FSI). Within the Watson-Migdal approximation the transition amplitude is factorized in terms of the production and FSI amplitudes. Further study were performed by Gottfried and Jackson [2] with introduction the absorptive correction to the Bor...

Starting from the phenomenologically successful color dipole representation of the diffractive structure function, we identify the dominant contribution to the diffractive cross section at small beta. The beta dependence is calculated taking advantage of the Regge factorization properties of the hard mechanism which drives the dependence on the diffractive mass. We impose the unitarity constrai...

We calculate the cross section for the dissociation of J/ψ by kaons within the framework of a meson exchange model. We find that, depending on the values of the coupling constants used, the cross section can vary from 5 mb to 30 mb at √ s ∼ 5 GeV. In relativistic heavy ion collisions J/ψ suppression has been recognized as an important tool to identify the possible phase transition to quark-gluo...

The BFKL dynamics can be successfully tested at the future high energy ee linear collider. The total γγ cross-section is calculated in the Leading Log QCD dipole picture of BFKL dynamics, and compared with the one from 2-gluon exchange. The rapidity dependence of the cross-section remains a powerful tool to increase the ratio between the BFKL and the 2-gluon cross-sections and is more sensitive...

The ee → eeπ + X and ee → eeKS + X reactions are studied at LEP using data collected with the L3 detector at √ s = 189−202 GeV. Preliminary results for the differential cross section dσ/dpT in the transverse momentum range 0.2 GeV < pT < 7.5 GeV at central values of pseudo-rapidity, |η| < 0.5 or |η| < 1.5, and the differential cross section dσ/d|η| for different values of pT are presented. For ...