Analysis of 2S singly heavy baryons in HQET

In this paper, we have employed HQET to determine the masses of radially excited (n=2) S-wave charm and bottom baryons. The HQET Lagrangian containing the non-perturbative parameters is shown with heavy baryon fields. The non-perturbative parameters, couplings, and decay widths are also studied for the S-wave singly heavy baryons. The HQET parameters Lambda<overline>, lambda 1 and lambda 2 are calculated for the ground state (n=1) using the masses of S-wave baryons. The 1S mass short-distance mass scheme is employed to estimate the heavy quark masses and non-perturbative parameters. The mass term ratios of n=1 and n=2 mesons and baryons containing parameters Lambda<overline> and lambda 1 are studied by varying the bottom quark mass. This analysis shows that heavy quarks behave the same inside mesons and baryons in both 1S and 2S states. The HQET symmetry of Lambda<overline> is used to find the parameters and masses for n=2 S-wave baryons. The variation of mass of 2S baryons with the non-perturbative parameters lambda 1 and lambda 2 is discussed. The Regge trajectories are also plotted in the (n,M2) plane using masses of n=1 and 2 charm and bottom baryons. The Regge trajectories are parallel and equidistant lines in the (n,M2) plane. We have also studied the strong decays of charm and bottom baryons for both n=1 and n=2 states. We have estimated the coupling constants g1=0.913-0.017+0.010 and g2=0.559-0.010+0.006 for n=1, and g1g2=1.52 for n=2. We have also shown the semi-electronic decay rates of charm baryons in the spectator heavy quark approximation for 1S -> 1S, 2S -> 1S, and 2S -> 2S transitions. The decay rates for 1S -> 1S transitions are of the same order as 2S -> 2S transitions. This analysis agrees well with the available theoretical and experimental data.