Coherent and noncoherent double diffractive production of Q(Q)over-bar pairs in heavy-ion collisions at high energies

The coherent and noncoherent double diffractive production of heavy quark-a ntiquark pairs in ion scattering at the LHC energies has been considered. T he total and differential cross sections for such processes featuring the p roduction of c (c) over bar and b (b) over bar quark pairs in pp, CaCa, and PbPb collisions have been estimated. It has been shown that the fraction o f heavy quark-antiquark pairs produced in double diffractive scattering amo unts to a few percent of the number of Q (Q) over bar pairs produced in har d QCD scattering; therefore, it is necessary to take into account such proc esses in detecting heavy quarks, in seeking Higgs bosons of intermediate ma ss, in investigating the suppression of heavy quarkonia in quark-gluon plas ma, and so on. It has been demonstrated that the cross section for coherent scattering is so large that this process can be used to study collective e ffects in nuclei at high energies. Large values of the quark-antiquark inva riant mass, M-Q (Q) over bar greater than or similar to 100 GeV, in associa tion with a large rapidity gap between diffractive jets, Delta eta > 5, exe mplify manifestations of such nuclear interactions.