Diffractive production of heavy mesons at the LHC

We discuss diffractive production of heavy mesons at the LHC. In addition to standard collinear approach, for a first time we propose a k(t)-factorization approach to the diffractive processes. The unintegrated (transverse momentum dependent) diffractive parton distributions in proton are calculated with the help of the Kimber-Martin-Ryskin prescription where collinear diffractive PDFs are used as input. Some correlation observables, like azimuthal angle correlation between c and c, and cc pair transverse momentum distribution were obtained for the first time. The results of the new approach are compared with those of the standard collinear one. Significantly larger cross sections are obtained in the k(t)-factorization approach where some part of higher-order effects is effectively included.