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Forero, D. V., & Guzzo, M. M. (2011). Constraining nonstandard neutrino interactions with electrons. Phys. Rev. D, 84(1), 013002–7pp.
Abstract: We update the phenomenological constraints of the nonstandard neutrino interactions (NSNI) with electrons including in the analysis, for the first time, data from LAMPF, Krasnoyarsk, and the latest Texono observations. We assume that NSNI modify the cross section of elastic scattering of (anti) neutrinos off electrons, using reactor and accelerator data, and the cross section of the electron-positron annihilation, using the four LEP experiments, in particular, new data from DELPHI. We find more restrictive allowed regions for the NSNI parameters: -0.11< epsilon(eR)(ee) < 0.05 and -0.02 < epsilon(eL)(ee) < 0.09 (90% C.L.). We also recalculate the parameters of tauonic flavor obtaining -0.35 < epsilon(eR)(tau tau) < 0.50 and -0.51 < epsilon(eL)(tau tau) < 0.34 (90% C.L.). Although more severe than the limits already present in the literature, our results indicate that NSNI are allowed by the present data as a subleading effect, and the standard electroweak model continues consistent with the experimental panorama at 90% C.L. Further improvement on this picture will deserve a lot of engagement of upcoming experiments.
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Binosi, D., Mezrag, C., Papavassiliou, J., Roberts, C. D., & Rodriguez-Quintero, J. (2017). Process-independent strong running coupling. Phys. Rev. D, 96(5), 054026–7pp.
Abstract: We unify two widely different approaches to understanding the infrared behavior of quantum chromodynamics (QCD), one essentially phenomenological, based on data, and the other computational, realized via quantum field equations in the continuum theory. Using the latter, we explain and calculate a process-independent running coupling for QCD, a new type of effective charge that is an analogue of the Gell-Mann-Low effective coupling in quantum electrodynamics. The result is almost identical to the process-dependent effective charge defined via the Bjorken sum rule, which provides one of the most basic constraints on our knowledge of nucleon spin structure. This reveals the Bjorken sum to be a near direct means by which to gain empirical insight into QCD's Gell-Mann-Low effective charge.
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Domingo, F., Kim, J. S., Martin Lozano, V., Martin-Ramiro, P., & Ruiz de Austri, R. (2020). Confronting the neutralino and chargino sector of the NMSSM with the multilepton searches at the LHC. Phys. Rev. D, 101(7), 075010–29pp.
Abstract: We test the impact of the ATLAS and CMS multilepton searches performed at the LHC with 8 as well as 13 TeV center-of-mass energy (using only the pre-2018 results) on the chargino and neutralino sector of the next-to-minimal supersymmetric Standard Model (NMSSM). Our purpose consists in analyzing the actual reach of these searches for a full model and in emphasizing effects beyond the minimal supersymmetric Standard Model (MSSM) that affect the performance of current (MSSM-inspired) electroweakino searches. To this end, we consider several scenarios characterizing specific features of the NMSSM electroweakino sector. We then perform a detailed collider study, generating Monte Carlo events through PYTHIA and testing against current LHC constraints implemented in the public tool CheckMATE. We find e.g., that supersymmetric decay chains involving intermediate singlino or Higgs-singlet states can modify the naive MSSM-like picture of the constraints by inducing final states with softer or less easily identifiable SM particles-reversely, a compressed configuration with singlino next-to-lightest supersymmetric particle occasionally induces final states that are rich with photons, which could provide complementary search channels.
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Forero, D. V., Morisi, S., Romao, J. C., & Valle, J. W. F. (2013). Neutrino mixing with revamped A(4) flavor symmetry. Phys. Rev. D, 88(1), 016003–7pp.
Abstract: We suggest a minimal extension of the simplest A(4) flavor model that can induce a nonzero theta(13) value, as required by recent neutrino oscillation data from reactors and accelerators. The predicted correlation between the atmospheric mixing angle theta(23) and the magnitude of theta(13) leads to an allowed region substantially smaller than indicated by neutrino-oscillation global fits. Moreover, the scheme correlates CP violation in neutrino oscillations with the octant of the atmospheric mixing parameter theta(23) in such a way that, for example, maximal mixing necessarily violates CP. We briefly comment on other phenomenological features of the model.
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de Anda, F. J., Medina, O., Valle, J. W. F., & Vaquera-Araujo, C. A. (2023). Revamping Kaluza-Klein dark matter in an orbifold theory of flavor. Phys. Rev. D, 108(3), 035046–11pp.
Abstract: We suggest a common origin for dark matter, neutrino mass and family symmetry within the orbifold theory proposed in [Phys. Lett. B 801, 135195 (2020); Phys. Rev. D 101, 116012 (2020)]. Flavor physics is described by an A(4) family symmetry that results naturally from compactification. Weakly interacting massive particle dark matter emerges from the first Kaluza-Klein excitation of the same scalar that drives family symmetry breaking and neutrino masses through the inverse seesaw mechanism. In addition to the “golden” quark-lepton mass relation and predictions for 0 nu beta beta decay, the model provides a good global description of all flavor observables.
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