Study Of The Strong Decays Of ?_c

Quantum chromodynamics(QCD)is the fundamental theory of the strong inter-action,which is responsible for the dynamics of hadrons.However,the connection of QCD to hadron is not very clear.People have to understand hadrons through their mass-es,productions and decays in all kinds of models.Thereinto,the consituent quark model with the QCD-motivated has been very successful and attractive in the study of hadronic spectrum and decay.In this paper,we study baryon structure and dynamical properties in the framework of the consituent quark model.The strong decay of baryon is one of the powerful methods to study baryon structure and dynamics.The model based on the quark pair production mechanism,compared with the theory of heavy hadron chiral perturbation theory and chiral quark model,it considers both baryon and mesons as particles with internal structure,which is more advantageous to the study of the internal structure of baryon.In addition,the microscopic decay model is considered to be the most closely related to QCD,which attempts to explain the mechanism of the vacuum quark pair production,and all models based on the vacuum quark production mechanism can be obtained as its special limiting cases.The very successful one is the 3p0 model.Therefore,the 3P0 model is applied to the calculation of the strong decay of ?_cbaryon.In recent years,except for ?_c(2930)and ?_c(3123)observed only in one experimen-t,more and more highly excited charmed strange baryons such as ?_c(2790),?_c(2815),?_c(2980),?_c(3055),and ?_c(3080)have been observed in different experiments[1].So far,the spins and parities of these ?_c have not yet been measured by experiment.other-wise,the mass spectra and the strong decays of excited ?_c baryons have been comput-ed in many models.The results indicate that the JP assignments of ?_c(2790)(1/2-)and?_c(2815)(3/2-)are the same in all references.However,there are different Jp assignments for other excited ?_c(2930),?_c(2980),?_c(3055),?_c(3080),and ?_c(3123).So,how to determine their spins and parities is an important theoretical topic.It is noticed that the systematical study of all these excited ?_c in the 3P0 model has not yet been performed.In order to understand their in-ternal structure and to determine their spin-parities,the strong decay proper-ties of these baryons as possible,and wave excited candidates have been sys-tematically studied in a 3P0 model.Possible configurations and assignments of ?_c(2790),?_c(2815),?_c(2930),?_c,(2980),?_c(3055),?_c(3080),and ?_c(3123)have been analyzed in comparison with experimental data.Our main conclusions are as follows:1,?_c(2790)and ?_c(2815)are very possibly the Pwave excited ?_c1(1/2-)and?_c1(3/2-),respectively.2,?_c(2930)may be the P wave excited?_c0(1/2-),?_c0(1/2-),?_c2(3/2-)?_c2(5/2-)?_c2(3/2-)or ?_c2(5/2-);or may be a 2S wave excited ?_c1(1/2+)?or?_c1(3/2+)?or may be a D wave excited?_c1(1/2+),?_c10(1/2+),?_c12(1/2+)?_c1(3/2+)?_c10(3/2+)or?_c12(3/2+)3,Ec.(2980)may be the Pwave excited ?_c1(1/2-);or may be a 2S wave excited?_c1(1/2+)or ?_c0(1/2+)with Jp=1/2+;or may be a D wave excited ?_c00(1/2+)or?_c10(1/2+)with Jp=1/2+.Jp=1/2+.4,?_c(3055)may be a 2S wave excited ?_c1(3/2+)or ?_c0(1/2+);or may be aD wave excited ?_c1(3/2+),?_c2(5/2+)?_c2(3/2+)or ?_c2(5/2+);seem impossible to be the P wave excited?_c.5,?_c(3080)may be a 2S wave excited ?_c0(1/2+);seem impossible to be the D and P wave excited ?_c.6,?_c(3123)seem impossible to be theP wave excited ?_c,but as possible D and wave excited 2S candidates,for the poor experimental information,it is impossible to identify this state at present.In addition,in the calculation of P,2S and D wave of excited ?_c,it is found that only the excited ?_c without ? mode excitation(with quantum number n?=L?=0)may decay into AD.The width of other excited ?_c,with non-vanish n? = L??0 decaying into ?D mode vanishes.