Diffractive exclusive production of heavy quark pairs at high energy proton-proton collisions

We discuss exclusive double diffractive (EDD) production of heavy quark - heavy antiquark pairs at high energies. Differential distributions for $c \bar c$at$\sqrt{s}$=1.96GeVandfor$b \bar b$at$\sqrt{s}$ = 14 TeV are shown and discussed. Irreducible leading-order $b\bar{b}$ background to Higgs production is calculated for the first time in several kinematical variables. The signal-to-background ratio is shown and several improvements are suggested.