Application of the QCD light cone sum rule to tetraquarks: The strong vertices XbXb rho and XcXc rho

Abstract

The full version of the QCD light-cone sum rule method is applied to tetraquarks containing a single heavy b or c quark. To this end, investigations of the strong vertices XbXb rho and XcXc rho are performed, where X-b = [su][(b) over bar(d) over bar] and X-c = [su][(c) over bar(d) over bar] are the exotic states built of four quarks of different flavors. The strong coupling constants G(XbXb rho) and G(XcXc rho) corresponding to these vertices are found using the rho-meson leading- and higher-twist distribution amplitudes. In the calculations, X-b and X-c are treated as scalar bound states of a diquark and antidiquark.