Abstract: | In this paper,the theory of mesonic Bethe-Salpeter equation with instantaneousinteraction is generalized to the case where the mass of the straton is not equal tothat of the antistraton.Assuming that the stratons are heavy and the interaction isdominantly a pseudoscalar potential and a static vector potential,we derive the SU(4)mass splitting for mesons.The difficulties encountered by the first order SU(4)massrelations after the discovery of charmed particles are analyzed.It is pointed out thatthese difficulties disappear in our mass relations.In particular,the mass formulaobtained with the potential of harmonic oscillator may explain not only the masses ofboth ground states and radial excited states,but also the effective masses of stratons,while the latter is compatible with the mass values for explaining the magnetic momentsof baryons.Finally,we discuss the newly discovered heavy particle Υ using our mass relations. |