Liang, W. H., Xiao, C. W., & Oset, E. (2014). Baryon states with open beauty in the extended local hidden gauge approach. Phys. Rev. D, 89(5), 054023–15pp.
Abstract: In this paper, we examine the interaction of (B) over barN, (B) over bar Delta, (B) over bar *N, and (B) over bar*Delta states, together with their coupled channels, by using a mapping from the light meson sector. The assumption that the heavy quarks act as spectators at the quark level automatically leads us to the results of the heavy quark spin symmetry for pion exchange and reproduces the results of the Weinberg Tomozawa term, coming from light vector exchanges in the extended local hidden gauge approach. With this dynamics we look for states dynamically generated from the interaction and find two states with nearly zero width, which we associate to the A(b)(5912) and A(b)(5920) states. The states couple mostly to (B) over bar *N, which are degenerate with the Weinberg Tomozawa interaction. The difference of masses between these two states, with J = 1/2 and 3/2, respectively, is due to pion exchange connecting these states to intermediate (B) over barN states. In addition to these two A(b) states, we find three more states with I = 0, one of them nearly degenerate in two states of J = 1/2, 3/2. Furthermore, we also find eight more states in I = 1, two of them degenerate in J = 1/2, 3/2, and another two degenerate in J = 1/2, 3/2, 5/2.
|
Liang, W. H., & Oset, E. (2014). B-0 and B-s(0) decays into J/psi f(0)(980) and J/psi f(0)(500) and the nature of the scalar resonances. Phys. Lett. B, 737, 70–74.
Abstract: We describe the B-0 and B-s(0) decays into J/psi f(0)(500) and J/psi f(0)(980) by taking into account the dominant process for the weak decay of B-0 and B-s(0) into J/psi and a q (q) over bar component. After hadronization of this q (q) over bar component into pairs of pseudoscalar mesons we obtain certain weights for the meson-meson components and allow them to interact among themselves. The final state interaction of the meson-meson components, described in terms of chiral unitary theory, gives rise to the f(0)(980) and f(0)(500) resonances and we can obtain the pi(+)pi(-) invariant mass distributions after the decay of the resonances, which allows us to compare directly to the experiments. We obtain ratios of J/psi f(0)(980) and J/psi f(0)( 500) for each of the B decays in quantitative agreement with experiment, with the f(0)(980) clearly dominant in the B-s(0) decay and the f(0)(500) in the B-0 decay.
|
Bayar, M., Liang, W. H., & Oset, E. (2014). B-0 and B-s(0) decays into J/psi plus a scalar or vector meson. Phys. Rev. D, 90(11), 114004–9pp.
Abstract: We extend a recent approach to describe the B-0 and B-s(0) decays into J/psi f(0)(500) and J/psi f(0)(980), relating it to the B-0 and B-s(0) decays into J/psi and a vector meson, phi, rho, K*. In addition, the B-0 and B-s(0) decays into J/psi and kappa(800) are evaluated and compared to the K* vector production. The rates obtained are in agreement with the available experiment while predictions are made for the J/psi plus kappa(800) decay.
|
Liang, W. H., Uchino, T., Xiao, C. W., & Oset, E. (2015). Baryon states with open charm in the extended local hidden gauge approach. Eur. Phys. J. A, 51(2), 16–14pp.
Abstract: In this paper we examine the interaction of DN and D* N states, together with their coupled channels, by using an extension of the local hidden gauge formalism from the light meson sector, which is based on heavy quark spin symmetry. The scheme is based on the use of the impulse approximation at the quark level, with the heavy quarks acting as spectators, which occurs for the dominant terms where there is the exchange of a light meson. The pion exchange and the Weinberg-Tomozawa interactions are generalized and with this dynamics we look for states generated from the interaction, with a unitary coupled channels approach that mixes the pseudoscalar-baryon and vector-baryon states. We find two states with nearly zero width, which are associated to the I > (c) (2595) and I > (c) (2625). The lower state, with J (P) = 1/2(-), couples to DN and D* N, and the second one, with J (P) = 3/2(-), to D* N. In addition to these two I > (c) states, we find four more states with I = 0, one of them nearly degenerate in two states of J (P) = 1/2, 3/2. Furthermore we find three states in I = 1, two of them degenerate in J = 1/2, 3/2.
|
Liang, W. H., Molina, R., Xie, J. J., Doring, M., & Oset, E. (2015). Predictions for the X(YZ) and X(YZ) with X(4160), Y(3940), Z(3930). Eur. Phys. J. A, 51(5), 58–7pp.
Abstract: We investigate the decay of and with R being the , , resonances. Under the assumption that these states are dynamically generated from the vector-vector interaction, as has been concluded from several theoretical studies, we use a reaction mechanism of quark production at the elementary level, followed by hadronization of one final pair into two vectors and posterior final state interaction of this pair of vector mesons to produce the resonances. With this procedure we are able to predict five ratios for these decays, which are closely linked to the dynamical nature of these states, and also predict the order of magnitude of the branching ratios which we find of the order of , well within the present measurable range. In order to further test the dynamical nature of these resonances we study the and decays close to the and thresholds and make predictions for the ratio of the mass distributions in these decays and the decay widths. The measurement of these decays rates can help unravel the nature of these resonances.
|
