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Sarkar, S., Sun, B. X., Oset, E., & Vicente Vacas, M. J. (2010). Dynamically generated resonances from the vector octet-baryon decuplet interaction. Eur. Phys. J. A, 44(3), 431–443.
Abstract: We study the interaction of the octet of vector mesons with the decuplet of baryons using Lagrangians of the hidden gauge theory for vector interactions. The unitary amplitudes in coupled channels develop poles that can be associated with some known baryonic resonances, while there are predictions for new ones at the energy frontier of the experimental research. The work offers guidelines on how to search for these resonances.
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Martinez Torres, A., & Oset, E. (2010). The gamma d -> K(+)K(-)np reaction and an alternative explanation for the “Theta(+)(1540) pentaquark” peak. Phys. Rev. C, 81(5), 055202–16pp.
Abstract: We present a calculation of the gamma d -> K(+)K(-)np reaction with the aim of seeing whether the experimental peak observed in the K(+)n invariant mass around 1526 MeV, from where evidence for the existence of the Theta(+) has been claimed, can be obtained without this resonance as a consequence of the particular dynamics of the process and the cuts applied in the experimental setup. We find that a combination of facts leads indeed to a peak around 1530 MeV for the invariant mass of K(+)n without the need to invoke any new resonance around this energy. This, together with statistical fluctuations that we prove to be large with the statistics of the experiment, is likely to produce the narrower peak observed there.
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Geng, L. S., Guo, F. K., Hanhart, C., Molina, R., Oset, E., & Zou, B. S. (2010). Study of the f(2)(1270) , f(2)'(1525) , f(0)(1370) and f(0)(1710) in the J/psi radiative decays. Eur. Phys. J. A, 44(2), 305–311.
Abstract: In this paper we present an approach to study the radiative decay modes of the J/psi into a photon and one of the tensor mesons f (2)(1270) , f' (2)(1525) , as well as the scalar ones f (0)(1370) and f (0)(1710) . Especially, we compare predictions that emerge from a scheme where the states appear dynamically in the solution of vector meson-vector meson scattering amplitudes to those from a (admittedly naive) quark model. We provide evidence that it might be possible to distinguish amongst the two scenarios, once improved data are available.
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Branz, T., Geng, L. S., & Oset, E. (2010). Two-photon and one-photon-one-vector meson decay widths of the f(0)(1370), f(2)(1270), f(0)(1710), f(2)'(1525), and K-2*(1430). Phys. Rev. D, 81(5), 054037–10pp.
Abstract: We calculate the radiative decay widths, two-photon (gamma gamma) and one-photon-one-vector meson (V gamma), of the dynamically generated resonances from vector-meson -vector-meson interaction in a unitary approach based on the hidden-gauge Lagrangians. In the present paper we consider the following dynamically generated resonances: f(0)(1370), f(0)(1710), f(2)(1270), f(2)'(1525) K-2*(1430), two strangeness 0 and isospin 1 states, and two strangeness 1 and isospin 1= 2 states. For the f(0)(1370) and f(2)(1270) we reproduce the previous results for the two-photon decay widths and further calculate their one-photon -one-vector decay widths. For the f(0)(1710) and f(2)'(1525) the calculated two-photon decay widths are found to be consistent with data. The rho 0 gamma, omega gamma and phi gamma decay widths of the f0(1370), f(2)'(1270) f(0)(1710), f(2)'(1525) are compared with the results predicted by other approaches. The K*(+)gamma and K*(0)gamma decay rates of the K-2*(1430) are also calculated and compared with the results obtained in the framework of the covariant oscillator quark model. The results for the two states with strangeness 0, isospin 1 and two states with strangeness 1, isospin 1/ 2 are predictions that need to be tested by future experiments.
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Roca, L., & Oset, E. (2010). Asymmetry observables in e(+)e(-) -> pi(+) pi(-) gamma in the phi region within a chiral unitary approach. Phys. Rev. D, 81(1), 014010–8pp.
Abstract: We make a theoretical study of the charge and forward-backward pion asymmetries in the e(+)e(-) -> pi(+) pi(-) gamma process on and off the phi resonance energy. These observables are rather sensitive to the inner details of the theoretical models to describe the reaction. In addition to the standard implementation of the initial state radiation and the bremsstrahlung contribution to the final state radiation, we use the techniques of the chiral unitary approach to evaluate the contribution from the mechanisms of phi decay into pi(+) pi(-) gamma. This contribution involves the implementation of final state interaction from direct chiral loops, the exchange of vector and axial-vector resonances and the final state interaction through the consideration of the meson-meson unitarized amplitudes, which were found important in a previous work describing the phi -> pi pi gamma. We find a good reproduction of the experimental data from KLOE for the forward-backward asymmetry, both at the phi peak and away from it. We also make predictions for the angular distributions of the charge asymmetry and show that this observable is very sensitive to the chiral loops involved in phi radiative decay.
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