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Sakai, S., Oset, E., & Ramos, A. (2018). Triangle singularities in B- -> K- pi- D(s0)+ and B- -> K- pi- D(s1)+. Eur. Phys. J. A, 54(1), 10–14pp.
Abstract: We study the appearance of structures in the decay of the B- into K-pi D--(s0)+ (2317) and K-pi D--(s1)+ (2460) final states by forming invariant mass distributions of pi D--(s0)+ and pi D--(s1)+ pairs, respectively. The structure in the distribution is associated to the kinematical triangle singularity that appears when the B- -> K- K*(0) D-0 (B- -> K- K*(0) D*(0)) decay process is followed by the decay of the K*(0) into pi(-) K+ and the subsequent rescattering of the K+ D-0 (K+ D*(0)) pair forming the D-s0(+) (2317) (D-s1(+) (2460)) resonance. We find this type of non-resonant peaks at 2850MeV in the invariant mass of pi D--(s0) pairs from B- -> K- pi(-) D-s0(+) (2317) decays and around 3000MeV in the invariant mass of pi D--(s1)+ pairs from B- -> K- pi(-) D-s1(+)(2460) decays. By employing the measured branching ratios of the B- -> K- K*(0) D-0 and B- -> K- K*(0) D*(0) decays, we predict the branching ratios for the processes B- into K-pi D--(s0)+ (2317) K-pi D--(s1)+ (2460), in the vicinity of the triangle singularity peak, to be about 8 x 10(-6) and 1 x 10(-6), respectively. The observation of this reaction would also give extra support to the molecular picture of the D-s0(+)(2317) and D-s1(+)(2460).
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Ertoprak, A. et al, Algora, A., Gadea, A., & Huyuk, T. (2018). M1 and E2 transition rates from core-excited states in semi-magic Ru-94. Eur. Phys. J. A, 54(9), 145–9pp.
Abstract: Lifetimes of high-spin states have been measured in the semi-magic (N = 50) nucleus Ru-94. Excited states in Ru-94 were populated in the Ni-58(Ca-40, 4p)Ru-94* fusion-evaporation reaction at the Grand Accelerateur National d'Ions Lourds (GANIL) accelerator complex. DSAM lifetime analysis was performed on the Doppler broadened line shapes in energy spectra obtained from gamma-rays emitted while the residual nuclei were slowing down in a thick 6 mg/cm(2) metallic Ni-58 target. In total eight excited-state lifetimes in the angular momentum range I = (13-20)h have been measured, five of which were determined for the first time. The corresponding B(M1) and B(E2) reduced transition strengths are discussed within the framework of large-scale shell model calculations to study the contribution of different particle-hole configurations, in particular for analyzing contributions from core-excited configurations.
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Rinaldi, M., & Vento, V. (2018). Scalar and tensor glueballs as gravitons. Eur. Phys. J. A, 54(9), 151–7pp.
Abstract: The bottom-up approach of the AdS/CFT correspondence leads to the study of field equations in an AdS(5) background and from their solutions to the determination of the hadronic mass spectrum. We extend the study to the equations of AdS(5) gravitons and determine from them the glueball spectrum. We propose an original presentation of the results which facilitates the comparison of the various models with the spectrum obtained by lattice QCD. This comparison allows to draw some phenomenological conclusions.
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Dai, L. R., & Oset, E. (2018). Polarization amplitudes in VP decay beyond the Standard Model. Eur. Phys. J. A, 54(12), 219–10pp.
Abstract: We study the amplitudes of the -VP decay for the different polarizations of the vector meson V, using a formalism where the mapping from the quark degrees of freedom to the meson ones is done with the P-3(0) model. We extend the formalism to a case, with the operator -5, that can account for different models beyond the Standard Model and study in detail the -K*0K- reaction for the different polarizations of the K*0. The results are shown in terms of the parameter that differs for each model. We find that is very different for each of the third components of the vector spin, M=+/- 1,0, and in particular the magnitude |M=-1 is very sensitive to the parameter, which makes the investigation of this magnitude very useful to test different models beyond the Standard Model.
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Xie, J. J., Liang, W. H., & Oset, E. (2019). eta-He-4 interaction from the dd->eta He-4 reaction near threshold. Eur. Phys. J. A, 55(1), 6–8pp.
Abstract: .We analyze the data on the total cross sections for the dd4 He reaction close to threshold and look for possible 4 He bound states. We develop a framework in which the 4 He optical potential is the key ingredient, rather than parameterizing the scattering matrix, as is usually done. The strength of this potential, together with some production parameters, are fitted to the available experimental data. The relationship of the scattering matrix to the optical potential is established using the Bethe-Salpeter equation and the 4 He loop function incorporates the range of the interaction given by the experimental He-4 density. However, when we look for poles of the scattering matrix, we get poles in the bound region, poles in the positive energy region or no poles at all. If we further restrict the results with constraints from a theoretical model with all its uncertainties the bound states are not allowed. However, we find a bump structure in |T|2 of the 4 He 4 He scattering amplitude below threshold for the remaining solutions.
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