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Hiller Blin, A. N., Sun, Z. F., & Vicente Vacas, M. J. (2018). Electromagnetic form factors of spin-1/2 doubly charmed baryons. Phys. Rev. D, 98(5), 054025–13pp.
Abstract: We study the electromagnetic form factors of the doubly charmed baryons, using covariant chiral perturbation theory within the extended on-mass-shell scheme. Vector-meson contributions are also taken into account. We present results for the baryon magnetic moments, charge, and magnetic radii. While some of the chiral Lagrangian parameters could be set to values determined in previous works, the available lattice results for Xi(+)(CC) and Omega(+)(CC) only allow for robust constraints on the low-energy constant combination, c(89) (= -1/3 c(8) + 4c(9)). The couplings of the doubly charmed baryons to the vector mesons have been estimated assuming the Okubo-Zweig-Iizuka rule. We also give the expressions for the form factors of the double-beauty baryons considering the masses predicted in the framework of quark models. A comparison of our results with those obtained in heavy baryon chiral perturbation theory at the same chiral order is made.
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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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Sajjad Athar, M., Ruiz Simo, I., & Vicente Vacas, M. J. (2011). Nuclear medium modification of the F2(x, Q^2) structure function. Nucl. Phys. A, 857(1), 29–41.
Abstract: We study the nuclear effects in the electromagnetic structure function F-2(x, Q(2)) in the deep inelastic lepton nucleus scattering process by taking into account Fermi motion, binding, pion and rho meson cloud contributions. Calculations have been done in a local density approximation using relativistic nuclear spectral functions which include nucleon correlations. The ratios R-F2(A) (x, Q(2)) = 2F(2)(A)(x, Q(2))/AF(2)(D)(x, Q(2)) are obtained and compared with recent JLab results for light nuclei with special attention to the slope of the x distributions. This magnitude shows a non-trivial A dependence and it is insensitive to possible normalization uncertainties. The results have also been compared with some of the older experiments using intermediate mass nuclei.
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Yao, D. L., Alvarez-Ruso, L., Hiller Blin, A. N., & Vicente Vacas, M. J. (2018). Weak pion production off the nucleon in covariant chiral perturbation theory. Phys. Rev. D, 98(7), 076004–25pp.
Abstract: Weak pion production off the nucleon at low energies has been systematically investigated in manifestly relativistic baryon chiral perturbation theory with explicit inclusion of the Delta(1232) resonance. Most of the involved low-energy constants have been previously determined in other processes such as pion-nucleon elastic scattering and electromagnetic pion production off the nucleon. For numerical estimates, the few remaining constants are set to be of natural size. As a result, the total cross sections for single pion production on neutrons and protons, induced either by neutrino or antineutrino, are predicted. Our results are consistent with the scarce existing experimental data except in the nu(mu)n -> mu(-)n pi(+) channel, where higher-order contributions might still be significant. The Delta resonance mechanisms lead to sizeable contributions in all channels, especially in nu(mu)p -> mu(-) p pi(+), even though the considered energies are close to the production threshold. The present study provides a well-founded low-energy benchmark for phenomenological models aimed at the description of weak pion production processes in the broad kinematic range of interest for current and future neutrino-oscillation experiments.
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Alvarez-Ruso, L., Nieves, J., Ruiz Simo, I., Valverde, M., & Vicente Vacas, M. J. (2013). Charged kaon production by coherent scattering of neutrinos and antineutrinos on nuclei. Phys. Rev. C, 87(1), 015503–11pp.
Abstract: With the aim of achieving a better and more complete understanding of neutrino interactions with nuclear targets, the coherent production of charged kaons induced by neutrinos and antineutrinos is investigated in the energy range of some of the current neutrino experiments. We follow a microscopic approach which, at the nucleon level, incorporates the most important mechanisms allowed by the chiral-symmetry-breaking pattern of QCD. The distortion of the outgoing K ((K) over bar) is taken into account by solving the Klein-Gordon equation with realistic optical potentials. Angular and momentum distributions, as well as the energy and nuclear dependence of the total cross section, are studied.
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