Strong decay of charmed baryons using quark-diquark Model Ajay Majethiya * , Kaushal Thakkar, and P C Vinodkumar * Kalol Institute of Technology and Research centre, Kalol. Department of Physics Sardar Patel University, Vallabh Vidyanagar, INDIA. * E-mail:ajay.phy@gmail.com Introduction Some new excited charmed baryons observed by Belle, BABAR and CLEO [1–3] have ini- tiated a great interest in the study of heavy baryons in both experiment and theory. The experimental information is still limited. So, it is important to understand the structures, spin-parity, decay, production and their in- teractions with other particles of new heavy flavour baryons theoretically. As adequate ex- perimental data are available in the charm sec- tor, our efforts would be to understand their properties based on the phenomenological de- scription using the quark-diquark model [4, 5]. In this paper, we report the spectroscopy and strong decay of the charmed baryons. By studying the strong decay modes, one expects to extract information about their structures and the low energy dynamics of heavy baryons vis a vis interaction with pion and other pseu- doscalar mesons. Methodology The Hamiltonian of the baryon, in the quark- diquark model, can be written in terms of di- quark Hamiltonian plus quark-diquark Hamil- tonian as [4, 5] H = H jk + H i,jk (1) The internal motion of the diquark(jk) is de- scribed by H d = H jk = p 2 2m jk + V jk (r jk ) (2) where, p is the relative momentum of the quarks within the diquark. The Hamiltonian of the relative motion of the diquark(jk) and the third quark(i) is given by H i,d = H i,jk = q 2 2m i,jk + V i,jk (r id ) (3) where, q is the relative momentum between the diquark and the third quark, m jk = mj m k mj +m k and m i,jk = mi(mj +m k ) m1+m2+m3 . In the diquark model, the potential energy can be written, as V = V jk (r jk )+ V i,jk (r id ) (4) Where, the diquark potential as well as the quark-diquark potential are assumed to be, [4, 5] V jk = - 2 3 α s 1 r jk +br ν jk ; V i,jk = - 4 3 α s 1 r id +br ν id (5) respectively. Here, ν is the potential ex- ponent, r id is the quark-diquark separation distance, α s the running strong coupling con- stant, b is the model parameter corresponding to the confining part of the potential, which is assumed to be same for the di-quark inter- action as well as between the quark-diquark interaction. The numerical approach using the Runge- Kutta method in a mathematica note book has been used to solve the Schrodinger equa- tion corresponds to the Hamiltonian as given in Eq.2 and 3. The degeneracy of the states are removed by introducing the spin dependent interaction po- tential given by [6]. Strong decay of charmed baryons The strong decay is computed as [7] Γ(Σ * c , Σ c → Λ c π)= g 2 2 2πf 2 π m Λc m Σc p 3 π (6) Proceedings of the DAE Symp.on Nucl. Phys. 55 (2010) 542 Avilable online at www.sympnp.org/proceedings