We explore the recently observed Ξ b (6227) − resonance to fix its quantum numbers. To this end, we consider various possible scenarios: It can be considered as either 1P /2S excitations of the Ξ − b and Ξ ′ b (5935) ground state baryons with spin-1 2 or 1P /2S excitations of the ground-state Ξ b (5955) with spin-3 2 . We calculate the masses of the possible angular-orbital 1P and 2S excited states corresponding to each channel employing the QCD sum rule technique. It is seen that all the obtained masses are in agreement with the experimentally observed value, implying that the mass calculations are not enough to determine the quantum numbers of the state under question. Therefore, we extend the analysis to investigate the possible decays of the excited states into Λ 0 b K − and Ξ − b π. Using the light cone QCD sum rule method, we calculate the corresponding strong coupling constants, which are used to extract the decay widths of the modes under consideration. Our results on decay widths indicate that the Ξ b (6227) − is 1P angular-orbital excited state of the Ξ b (5955) baryon with quantum numbers J P = 3 2 − .
I. INTRODUCTIONThe theoretical studies of the heavy baryons involving their spectroscopic parameters and the interaction mechanisms improve our understanding on the nonperturbative regime of the strong interaction, as well as their nature and internal structure. As a result of the impressive developments in the experimental sector in the last decade, almost all of the ground state baryons with single heavy quark were observed [1][2][3][4][5][6][7][8][9].The spectroscopy of the heavy baryons containing b quark has been investigated within different models. These approaches include the quark model [10][11][12][13][14][15][16][17][18][19], the QCD sum rule approach [20-24], lattice QCD [25], 1/N c and 1/m b expansions [26] and Faddeev approach [27]. To gain deeper understanding on the single bottom baryons, their properties such as magnetic dipole moments and strong decays were investigated in Refs. [28][29][30][31][32][33]. In Ref.[34], their strong and radiative decays were studied using the constituent quark model.The quark model predicts existence of many new baryons with one, two, or three heavy quarks. The impressive developments in the experimental techniques indicate that more heavy baryons would be observed in near future. With this motivation and the motivation brought by the recent observation of the LHCb Collaboration [35], we investigate the masses and decay constants of the low-lying 2S and 1P excited Ξ b baryons having J = 1 2 and J = 3 2 . The LHCb collaboration recently reported the observation of Ξ b (6227) − with mass m Ξ b (6227) − = 6226.9 ± 2.0 ± 0.3 ± 0.2 MeV and width Γ Ξ b (6227) − = 18.1 ± 5.4 ± 1.8 MeV. From the observed mass and decay modes, it was stated that Ξ b (6227) − state may be 1P or 2S excited baryon (see also [35]). After this observation, this state is considered in Ref.[36] and its mass and strong decays were analyzed. The obtained results indicated the possibility of...