Meloni, D., Morisi, S., & Peinado, E. (2011). Stability of dark matter from the D(4) x Z(2)(f) flavor group. Phys. Lett. B, 703(3), 281–287.
Abstract: We study a model based on the dihedral group D(4) in which the dark matter is stabilized by the interplay between a remnant Z(2) symmetry, of the same spontaneously broken non-abelian group, and an auxiliary Z(2)(f) introduced to eliminate unwanted couplings in the scalar potential. In the lepton sector the model is compatible with normal hierarchy only and predicts a vanishing reactor mixing angle, theta(13) = 0. Since m(nu 1) = 0, we also have a simple prediction for the effective mass in terms of the solar angle: vertical bar m(beta beta)vertical bar = vertical bar m(nu 2)vertical bar sin(2)theta circle dot similar to 10(-3) eV. There also exists a large portion of the model parameter space where the upper bounds on lepton flavor violating processes are not violated. We incorporate quarks in the same scheme finding that a description of the CKM mixing matrix is possible and that semileptonic K and D decays mediated by flavor changing neutral currents are under control.
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Roca, L., Liang, W. H., & Oset, E. (2022). Inconsistency of the data on the K-1(1270) -> pi K-0*(1430) decay width. Phys. Lett. B, 824, 136827–3pp.
Abstract: We show, using the same Lagrangian for the K-1(1270) -> pi K-0*(1430) and K-0*(1430) -> K-1 (1270)pi decays, that the present PDG data on the partial decay width of K-1 (1270) -> pi K-0*(1430) implies a width for K-0*(1430) -> K-1 (1270)pi decay which is about one order of magnitude larger than the total K-0*(1430) width. A discussion on this inconsistency is done, stressing its relationship to the existence of two K-1(1270) states obtained with the chiral unitary theory, which are not considered in the experimental analyses of K pi pi data.
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Oset, E., & Roca, L. (2018). Triangle mechanism in tau -> f(1)(1285)pi nu(tau) decay. Phys. Lett. B, 782, 332–338.
Abstract: We show that the tau(-) decay into f(1)(1285) pi(-)nu(tau) is dominated by a triangle loop mechanism with K*, (K) over bar* and K( or (K) over bar) as internal lines, which manifests a strong enhancement reminiscent of a nearby singularity present in the narrow K* limit and the near (K) over bar* K* threshold of the internal K* propagators. The f1(1285) is then produced by its coupling to the K* (K) over bar and (K) over bar* K which is obtained from a previous model where this resonance was dynamically generated as a molecular K* (K) over bar (or (K) over bar* K) state using the techniques of the chiral unitary approach. We make predictions for the f(1)pi mass distribution which significantly deviates from the phase-space shape, due to the distortion caused by the triangle mechanism and the K* (K) over bar threshold. We find a good agreement with the experimental value within uncertainties for the integrated partial decay width, which is a clear indication of the importance of the triangle mechanism in this decay and supports the dynamical origin of the f(1)(1285) as a K* (K) over bar and (K) over bar* K molecular state.
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Olmo, G. J., & Rubiera-Garcia, D. (2015). Brane-world and loop cosmology from a gravity-matter coupling perspective. Phys. Lett. B, 740, 73–79.
Abstract: We show that the effective brane-world and the loop quantum cosmology background expansion histories can be reproduced from a modified gravity perspective in terms of an f (R) gravity action plus a g(R) term non-minimally coupled with the matter Lagrangian. The reconstruction algorithm that we provide depends on a free function of the matter density that must be specified in each case and allows to obtain analytical solutions always. In the simplest cases, the function f (R) is quadratic in the Ricci scalar, R, whereas g(R) is linear. Our approach is compared with recent results in the literature. We show that working in the Palatini formalism there is no need to impose any constraint that keeps the equations second order, which is a key requirement for the successful implementation of the reconstruction algorithm.
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Bruschini, R., & Gonzalez, R. (2019). A plausible explanation of Upsilon(10860). Phys. Lett. B, 791, 409–413.
Abstract: We show that a good description of the Upsilon(10860) properties, in particular the mass, the e(+) e(-) leptonic widths and the pi(+) pi(-) Upsilon(ns) (n = 1, 2, 3) production rates, can be obtained under the assumption that Upsilon(10860) is a mixing of the conventional Upsilon(5s) quark model state with the lowest P-wave hybrid state.
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