Study Of The Process J/???c?

Charmonium is a bound state composed of a pair of positive and negative charm quarks through strong interaction.The first member of this family J/?was first observed in 1974.Subsequently,a series of charmonium states were dis-covered.These abundant experimental information provide valuable information for us to understand their decay mechanism and other information.The study of the charmonium radiative decay process can help us to understand the internal structure of hadrons better.The main contents are as followsThe first chapter briefly introduces some basic characteristics of quantum chromodynamics(QCD),and then gives a brief introduction to the charmonium particles studied in this paper,including J/?,?(2S),?c,?c(2S).The last part of this chapter contributes to the specific nature of the two major categories in radiative transitions.Among them,the study of J/???c? belongs to the magnetic dipole radiative transition.In the second chapter,we first take the meson p as an example to introduce several key steps in the application of QCD sum rule method,mainly including two processing methods starting from the constructed correlation function and the final Borel transformation.Then we introduce the difficulties of QCD sum rule,which leads to light cone sum rule method.Finally,we summarize the difference between QCD sum rule method and light cone sum rule method.In the third chapter,we calculate the form factor and decay width of the radiative transition process of J/??? From the point of view of our method,both the form factor and the decay width depend on the quark mass of c and the quark hadron duality hypothesis.Our result show that relativistic effect is notable,and the decay width obtained by this method is consistent with the current experimental values and other sum rule methods within the error range.In the fourth chapter,we summarize the work we have done and at the same time we give a prospect of our future work.