Examinando por Autor "Kovalenko, Sergey"
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Ítem An extended 3-3-1 model with radiative linear seesaw mechanism(Elsevier B.V., 2022-06-10) Cárcamo Hernández, A.E.; Kovalenko, Sergey; Queiroz, Farinaldo S.; Villamizar, Yoxara S.Motivated by the recent muon anomalous magnetic moment (g-2) measurement at FERMILAB and non-zero neutrino masses, we propose a model based on the SU(3)C×SU(3)L×U(1)X (3-3-1) gauge symmetry. The most popular 3-3-1 models in the literature require the presence of a scalar sextet to address neutrino masses. In our work, we show that we can successfully implement an one-loop linear seesaw mechanism with right-handed neutrinos, and vector-like fermions to nicely explain the active neutrino masses, and additionally reproduce the recent Muon g-2 result, in agreement with existing bounds. © 2022 The Author(s)Ítem Dark matter from a radiative inverse seesaw majoron model(Elsevier B.V., 2023-11-10) Bonilla, Cesar; Cárcamo Hernández, A. E.; Díaz Sáez, Bastián; Kovalenko, Sergey; Marchant González, JuanWe propose a Majoron-like extension of the Standard Model with an extra global U(1)X-symmetry where neutrino masses are generated through an inverse seesaw mechanism at the 1-loop level. In contrast to the tree-level inverse seesaw, our framework contains dark matter (DM) candidates stabilized by a residual Z2-symmetry surviving spontaneous breaking of the U(1)X-group. We explore the case in which the DM is a Majorana fermion. Furthermore, we provide parameter space regions allowed by current experimental constraints coming from the dark matter relic abundance, (in)direct detection, and charged lepton flavor violation. © 2023 The Author(s)Ítem Fermion mass hierarchy in an extended left-right symmetric model(Springer Science and Business Media Deutschland GmbH, 2023-12) Bonilla, Cesar; Cárcamo Hernández A.E.; Kovalenko, Sergey; Lee H.; Pasechnik R.; Schmidt, IvanWe present a Left-Right symmetric model that provides an explanation for the mass hierarchy of the charged fermions within the framework of the Standard Model. This explanation is achieved through the utilization of both tree-level and radiative seesaw mechanisms. In this model, the tiny masses of the light active neutrinos are generated via a three-loop radiative inverse seesaw mechanism, with Dirac and Majorana submatrices arising at one-loop level. To the best of our knowledge, this is the first example of the inverse seesaw mechanism being implemented with both submatrices generated at one- loop level. The model contains a global U(1) X symmetry which, after its spontaneous breaking, allows for the stabilization of the Dark Matter (DM) candidates. We show that the electroweak precision observables, the electron and muon anomalous magnetic moments as well as the Charged Lepton Flavor Violating decays, μ → eγ, are consistent with the current experimental limits. In addition, we analyze the implications of the model for the 95 GeV diphoton excess recently reported by the CMS collaboration and demonstrate that such anomaly could be easily accommodated. Finally, we discuss qualitative aspects of DM in the considered model.Ítem Fermion spectrum and g- 2 anomalies in a low scale 3-3-1 model(Springer Science and Business Media Deutschland GmbH, 2021-02) Cárcamo Hernández, A. E.; Hidalgo Velásquez, Yocelyne; Kovalenko, Sergey; Long, H. N.; A. Pérez-Julve, Nicolás; Vien, V. V.We propose a renormalizable theory based on the SU(3) C× SU(3) L× U(1) X gauge symmetry, supplemented by the spontaneously broken U(1)Lg global lepton number symmetry and the S3× Z2 discrete group, which successfully describes the observed SM fermion mass and mixing hierarchy. In our model the top and exotic quarks get tree level masses, whereas the bottom, charm and strange quarks as well as the tau and muon leptons obtain their masses from a tree level Universal seesaw mechanism thanks to their mixing with charged exotic vector like fermions. The masses for the first generation SM charged fermions are generated from a radiative seesaw mechanism at one loop level. The light active neutrino masses are produced from a loop level radiative seesaw mechanism. Our model successfully accommodates the experimental values for electron and muon anomalous magnetic dipole moments. © 2021, The Author(s).Ítem How many 1-loop neutrino mass models are there?(Springer Science and Business Media Deutschland GmbH, 2022-08) Arbeláez, Carolina; Cepedello, Ricardo; Helo, Juan Carlos; Hirsch, Martin; Kovalenko, SergeyIt is well-known that at tree-level the d = 5 Weinberg operator can be generated in exactly three different ways, the famous seesaw models. In this paper we study the related question of how many phenomenologically consistent 1-loop models one can construct at d=5. First, we discuss that there are two possible classes of 1-loop neutrino mass models, that allow avoiding stable charged relics: (i) models with dark matter candidates and (ii) models with “exits”. Here, we define “exits” as particles that can decay into standard model fields. Considering 1-loop models with new scalars and fermions, we find in the dark matter class a total of (115+203) models, while in the exit class we find (38+368) models. Here, 115 is the number of DM models, which require a stabilizing symmetry, while 203 is the number of models which contain a dark matter candidate, which maybe accidentally stable. In the exit class the 38 refers to models, for which one (or two) of the internal particles in the loop is a SM field, while the 368 models contain only fields beyond the SM (BSM) in the neutrino mass diagram. We then study the RGE evolution of the gauge couplings in all our 1-loop models. Many of the models in our list lead to Landau poles in some gauge coupling at rather low energies and there is exactly one model which unifies the gauge couplings at energies above 1015 GeV in a numerically acceptable way. © 2022, The Author(s).Ítem Low-scale seesaw from neutrino condensation(Elsevier B.V., 2020-03) Dib, Claudio; Kovalenko, Sergey; Schmidt, Ivan; Smetana, AdamKnowledge of the mechanism of neutrino mass generation would help understand a lot more about Lepton Number Violation (LNV), the cosmological evolution of the Universe, or the evolution of astronomical objects. Here we propose a verifiable and viable extension of the Standard model for neutrino mass generation, with a low-scale seesaw mechanism via LNV condensation in the sector of sterile neutrinos. To prove the concept, we analyze a simplified model of just a single family of elementary particles and check it against a set of phenomenological constraints coming from electroweak symmetry breaking, neutrino masses, leptogenesis and dark matter. The model predicts (i) TeV scale quasi-degenerate heavy sterile neutrinos, suitable for leptogenesis with resonant enhancement of the CP asymmetry, (ii) a set of additional heavy Higgs bosons whose existence can be challenged at the LHC, (iii) an additional light and sterile Higgs scalar which is a candidate for decaying warm dark matter, and (iv) a majoron. Since the model is based on simple and robust principles of dynamical mass generation, its parameters are very restricted, but remarkably it is still within current phenomenological limitsÍtem Neutrinoless double-electron capture(American Physical Society, 2020-12-16) Blaum K.; Eliseev S.; Danevich F.A.; Tretyak V.I.; Kovalenko, Sergey; Krivoruchenko M.I.; Novikov Yu.N.; Suhonen J.Double-beta processes play a key role in the exploration of neutrino and weak interaction properties, and in the searches for effects beyond the standard model. During the last half century many attempts were undertaken to search for double-beta decay with emission of two electrons, especially for its neutrinoless mode 0?2ß-, the latter having still not been observed. Double-electron capture (2EC) was not yet in focus because of its in general lower transition probability. However, the rate of neutrinoless double-electron capture 0?2EC can experience a resonance enhancement by many orders of magnitude when the initial and final states are energetically degenerate. In the resonant case, the sensitivity of the 0?2EC process can approach the sensitivity of the 0?2ß- decay in the search for the Majorana mass of neutrinos, right-handed currents, and other new physics. An overview of the main experimental and theoretical results obtained during the last decade in this field is presented. The experimental part outlines search results of 2EC processes and measurements of the decay energies for possible resonant 0?2EC transitions. An unprecedented precision in the determination of decay energies with Penning traps has allowed one to refine the values of the degeneracy parameter for all previously known near-resonant decays and has reduced the rather large uncertainties in the estimate of the 0?2EC half-lives. The theoretical part contains an updated analysis of the electron shell effects and an overview of the nuclear-structure models, in which the nuclear matrix elements of the 0?2EC decays are calculated. One can conclude that the decay probability of 0?2EC can experience a significant enhancement in several nuclides.Ítem Phenomenological and cosmological implications of a scotogenic three-loop neutrino mass model(Springer Science and Business Media Deutschland GmbH, 2023-03) Abada, Asmaa; Bernal, Nicolás; Cárcamo Hernández, Antonio E.; Kovalenko, Sergey; de Melo, Téssio B.; Toma, TakashiWe propose a scotogenic model for generating neutrino masses through a three-loop seesaw. It is a minimally extended inert doublet model with a spontaneously broken global symmetry U(1)′ and a preserved ℤ2 symmetry. The three-loop suppression allows the new particles to have masses at the TeV scale without fine-tuning the Yukawa couplings. The model leads to a rich phenomenology while satisfying all the current constraints imposed by neutrinoless double-beta decay, charged-lepton flavor violation, and electroweak precision observables. The relatively large Yukawa couplings lead to sizable rates for charged lepton flavor violation processes, well within future experimental reach. The model could also successfully explain the W mass anomaly and provides viable fermionic or scalar dark matter candidates. © 2023, The Author(s).Ítem Rare kaon decay to missing energy: Implications of the NA62 result for a Z′ model(American Physical Society, 2021-06) De Melo, Téssio B.; Kovalenko, Sergey; Queiroz, Farinaldo S.; Siqueira, C.; Villamizar, Yoxara S.Meson decays offer a good opportunity to probe new physics. The rare kaon decay K+→π+νν¯ is one of the cleanest of them and, for this reason, is rather sensitive to new physics, in particular, vector mediators. The NA62 Collaboration, running a fixed-target experiment at CERN, recently reported an unprecedented sensitivity to this decay, namely a branching fraction of BR(K+→π+νν¯)=(11-3.5+4.0)×10-11 at 68% C.L. Vector mediators that couple to neutrinos may yield a sizeable contribution to this decay. Motivated by the new measurement, we interpret this result in the context of a concrete Z′ model, and put our findings into perspective with the correlated KL→π0νν¯ decay measured by the KOTO Collaboration, current, and future colliders, namely the High-Luminosity and High-Energy Large Hadron Collider. © 2021 authors. Published by the American Physical Society.Ítem RGE effects on the LFV scale from meson decays(European Physical Journal C, 2022-04) González, Marcela; Kovalenko, Sergey; Neill, Nicolás A.; Vignatti, JonatanWe consider the lepton-flavor violating (LFV) lepton-quark dimension-6 operators and analyze their contributions to the LFV leptonic decays of vector, pseudoscalar, and scalar neutral mesons M→ ℓ1ℓ2 as well as to μ(τ) → ℓee, ℓγγ decays. These operators contribute to the purely leptonic processes via quark loop. On the basis of quark-hadron duality, we relate these loops to the appropriate meson-exchange contributions. In this way, we extract lower bounds on the individual scales of the studied LFV operators from the experimental and phenomenological limits on the leptonic decays of mesons and leptons. As a byproduct, we shall obtain new limits on the LFV leptonic decays of flavored mesons from the experimental bounds on the three-body lepton decays. We study the effects of QED and QCD radiative corrections to the LFV lepton-quark operators in question. We derive for them the one-loop matrix of the RGE evolution and examine its effect on the previously derived tree-level limits on these operators. We show that the QED corrections are particularly relevant due to operator mixing. Specifically, for some of them the limits on their individual LFV scales improve by up to 3 orders of magnitude. © 2022, The Author(s).Ítem Three-loop inverse scotogenic seesaw models(Springer Science and Business Media Deutschland GmbH, 2024-05-05) Abada, Asmaa; Bernal, Nicolás; Cárcamo Hernández A.E.; Kovalenko, Sergey; de Melo, Téssio B.We propose a class of models providing an explanation of the origin of light neutrino masses, the baryon asymmetry of the Universe via leptogenesis and offering viable dark matter candidates. In these models the Majorana masses of the active neutrino are generated by the inverse seesaw mechanism with the lepton number violating right-handed Majorana neutrino masses μ arising at three loops. The latter is ensured by the preserved discrete symmetries, which also guarantee the stability of the dark matter candidate. We focus on one of these models and perform a detailed analysis of the phenomenology of its leptonic sector. The model can successfully accommodate baryogenesis through leptogenesis in both weak and strong washout regimes. The lightest heavy fermion turns out to be a viable dark matter candidate, provided that the entries of the Majorana submatrix μ are in the keV to MeV range. The solutions are consistent with the experimental constraints, accommodating both mass orderings for active neutrinos, in particular charged-lepton flavor violating decays μ → eγ, μ → eee, and the electron-muon conversion processes get sizable rates within future sensitivity reach.