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Wave functions and annihilation widths of heavy quarkonia

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 Publication date 2020
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and research's language is English




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Within the framework of nonrelativistic quark-antiquark Cornell potential model formalism, we study the annihilation of heavy quarkonia. We determine their annihilation widths resulting into $gammagamma$, $gg$, $3gamma$, $3g$ and $gamma gg$ and compare our findings with the available theoretical results and experimental data. We also provide the charge radii and absolute square of radial Schrodinger wave function at zero quark-antiquark separation.

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We calculate the annihilation decay rates of the $^3D_2(2^{--})$ and $^3D_3(3^{--})$ charmonia and bottomonia by using the instantaneous Bethe-Salpeter method. The wave functions of states with quantum numbers $J^{PC}=2^{--}$ and $3^{--}$ are constructed. By solving the corresponding instantaneous Bethe-Salpeter 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 $3g$ channel are as follows: $Gamma_{^3D_2(cbar c)rightarrow ggg} = 9.24$ keV, $Gamma_{^3D_3(cbar c)rightarrow ggg}=25.0$ keV, $Gamma_{^3D_2(bbar b)rightarrow ggg}= 1.87$ keV, and $Gamma_{^3D_3(bbar b)rightarrow ggg}= 0.815$ keV.
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