Relativistic corrections to the exclusive decays of C-even bottomonia into S-wave charmonium pairs

Abstract

Within the nonrelativistic quantum chromodynamics (NRQCD) factorization formalism, we compute the relativistic corrections to the exclusive decays of bottomonia with even charge conjugation parity into S-wave charmonium pairs at leading order in the strong coupling constant. Relativistic corrections are resummed for a class of color-singlet contributions to all orders in the charm-quark velocity v_c in the charmonium rest frame.