Annihilation rates of 3D2(2--) and 3D3(3--) heavy quarkonia

We calculate the annihilation decay rates of the D-3(2)(2--) and D-3(3)(3(--)) charmonia and bottomonia by using the instantaneous Bethe-Salpeter (BS) method. The wave functions of states with quantum numbers J(PC) = 2(--) and 3(--) are constructed. By solving the corresponding instantaneous BS equations, we obtain the mass spectra and wave functions of the quarkonia. The annihilation amplitude is written within Mandelstam formalism and the relativistic corrections are taken into account properly. This is important, especially for high excited states, since their relativistic corrections are large. The results for the 3(g) channel are as follows: Gamma(13D2(cc ($) over bar) -> ggg) = 9.24 keV, Gamma(3)(1)(D3( cc ($) over bar) -> ggg) = 25.0 keV, Gamma(3)(1)(D2(bb ($) over bar) -> ggg) = 1.87 keV and Gamma(3)(1)(D3(bb ($) over bar) -> ggg) = 0.815 keV.