| The coupling constant of*has been studied by several authors using different approaches of the QCD sum rules.But the numerical results are not ideal and relatively small compared with CLEO experimental value2)*=17.9.This paper adopt the vector current(9?（）（8（）and the pseudovector current（8?（0）5（0）as interpolating current,to define a new correlation function.We isolate only the contribution of the ground state and assume that the higher states can be included in the perturbative estimate of a continuum.Here,we accurately calculate the contribution at twist-4 level of two-particles pion functions.Finally,the sum rules can be obtained by quark-hadron duality.In date calculation,we use two methods to fit the coupling constants.The result is2）*=16.25 and 12.23,2）*=34.69 and23.62. |
PDF Full Text Request