Research On Single Charm Quark Baryon Spectra In The Constituent Quark Model

Quantum chromodynamics (QCD) is the fundamental theory of the strong interaction. QCD theory contains the three basic properties namely the chiral symmetry, color confine-ment and asymptotic freedom. It’s worth pointing out that the asymptotic freedom char-acteristics can be accurately solved with perturbation theory during the process of dealing with the strong interaction in the high-energy region. But in the low energy region, it needs to adopt the non-perturbative theory. It is difficult to directly solve the non-perturbative effect with the theory of QCD. Therefore, in studying the low-energy hadronic properties, one need to use the phenomenological model in QCD spirit. Among them, the SU(3) chi-ral quark model proposed by Zhang Zongye can better explain the problems in the field of light quark such as the baryon ground state energy, deuteron binding energy, the scattering between hadrons and hadrons etc.. With more and more the heavy baryons are found, it’s one of the hot topics to study the heavy baryon spectra in the field of high energy physics. In present work, we study the ground state energy and the low-level excited state energy of the heavy baryon containing a single heavy quark in the constituent quark model.In present work, we use the new method of group theory-the eigen function method, to calculate the standard basis and the CG coefficients in permutation group which are needed to construct the heavy baryons’wave function of the three quark states. Then we calculate the ground state energy and the excited state energy of N≤2in SU(3) chiral quark model. In the constituent quark model, we have also calculated the ground state energy containing a single heavy quark baryon and the excited state energy of N≤2. And then based on the ground state energy of the experimentally eknown containing light baryon, one can fit the parameters associated with the light baryons and then obtain the the ground state energy and the excited state energy of the light baryon. The result shows that the theoretical values are in good agreement with the experimental values. In this condition, then according to the ground state energy of the experimentally known containing heavy baryon Ac、(?)c、(?)c’、∑c、αc, one can fit the parameters associated with the heavy baryons, thus obtain the the ground state energy and the excited state energy of the heavy baryon. The heavy baryons lack of more experimental data in the excited states. We make comparisons with only a few groups of the experimental value in excited states Ac、(?)c*, one can conclude that the theoretical value is overall lower than the experimental value. Since we have not considered the interaction between heavy and light quarks in the chiral potential, which might affect the result to some extent. As we know that the QCD theory points out that the baryon states in high excited region contain not only the internal three quark excitation, but also may have one or more pairs of quark antiquark from the vacuum, so in the later work one can take the interaction between heavy and light quarks in the chiral potential and the multi-quark state system into account.