Pentaquark Baryons Spectrum Which Containing Heavy Charm Quark In Quark Model

Since the quantum chromodynamics is proposed in last century seventy’s, through mounts of research by scientists, the theory of QCD is recognized as the basic theory of the strong interaction. We can solve it accurately in the low energy region by perturbation method. But for the high energy region, using the theory of QCD directly to deal with the strong interaction is very difficult due to the non perturbative properties, thus having to depend on some phenomenological theories. Especially, the quark model is the most successful.Baryon is composed of three quarks and mesotron is composed of positive and negative quark in traditional quark model. When in the high energy region, the theory of the quark model can explain well.But in the low energy high-excited states, derivation be-tween the theoretical value and the experimental value is a little large. Thus people think the baryon, additionally composed by the three quarks system, maybe also mix the multi-quark state. D.O.Riska, Zongye Zhang, Fan Wang Etc. use different models to make lots of research on the multi-quark spectrum in tetraquarks, pentaquarks and so on. In the recent years, the study on heavy baryon has become a new hot spot in the research on theoretical physics. Tetraquarks have more than one structure of the quarks. The present work is based on the quark model, using the new method of the group representation the-ory to construct the wave function of pentaquark containing the charm quark. The present work study the baryon containing five quarks qqqq-q-As the antiquark and four quark-s have no symmetry, we firstly separate anti quark out when in constructing the baryon wave function. We also calculate the CG coefficient of the S U(4) when f=7. We use the theory of group representation to construct the tetraquarks’wave function for all the spaces, and then couple them, ultimately including the anti-quarks’, thus obtaining the antisymmetric wave functions which are constrained by the pauli exclusion principle. By calculating all kinds of operator matrix elements in quark model, One can obtain the energy spectrum of baryon through the method of the solution of the eigenvalue equation.