Relativistic Corrections to the Higgs Boson Decay into a Pair of Vector Quarkonia.

We studied different mechanisms in the Higgs boson decay into a pair of J/psi and Upsilon particles within the perturbative Standard Model and relativistic quark model. The relativistic corrections to the decay amplitude and decay width were calculated. We obtained numerical values of the decay widths of the Higgs boson, which can be used for comparison with experimental data.