arXiv subjects

A. Doff

Publications and source records attributed to A. Doff.

At least 19 recordsLinked to original sources

arXiv2026

Scalar contributions from $331RHN$ minimal model to oblique parameters

Electroweak precision observables, encoded in the oblique parameters $S$, $T$, and $U$, impose stringent constraints on extensions of the Standard Model. In this work, we analyze the scalar-sector contributions to these parameters within the minimal 331RHN model. Building on previous results obtained in the 331RHN framework, we show that the oblique parameter $T$ provides the dominant constraint on the scalar mass spectrum. Our results indicate that current experimental bounds on $T$ lead to a nontrivial upper limit on the symmetry-breaking scale, $\omega \lesssim 10~\text{TeV}$. These findings highlight the sensitivity of electroweak precision data to the scalar sector of 3-3-1 models and their viability as extensions of the Standard Model.

hep-ph↗

arXiv2026

The 3-3-1 Model: a natural framework for sub-MeV dark matter

We show that the $\mathrm{SU}(3)_C \times \mathrm{SU}(3)_L \times \mathrm{U}(1)_N$ model with right-handed neutrinos naturally accommodates a viable sub-MeV dark matter (DM) candidate realized as pseudo-Goldstone boson that acquires tiny mass through gravitational effects. The observed relic abundance is obtained via freeze-in in a low-reheating temperature scenario, without requiring tiny couplings. The model operates at the TeV scale and remains testable at current and future collider experiments.

hep-ph↗

arXiv2026

Scalar contributions to the S, T, U parameters in a 3-3-1 model

Electroweak precision tests, expressed through the oblique parameters $S$, $T$, and $U$, impose stringent constraints on physics beyond the Standard Model. Gauge extensions of the Standard Model based on the $SU(3)_L \times U(1)_N$ symmetry predict a rich scalar and gauge spectrum that contribute to these parameters. Previous studies have shown that 3-3-1 gauge bosons give negligible contributions to the oblique parameters, while the contributions of the scalar sector to these parameters have received comparatively little attention. In particular, for the version of the $SU(3)_L \times U(1)_N$ model with right-handed neutrinos, the impact of the scalar sector on $S$, $T$ , and $U$ has not yet been addressed. In this work, we fill this gap and address sistematically the scalar contributions to the $S$, $T$ and $U$ within this version. As main result, we show that the parameter $T$ put stringent constraints on the masses and energy scales associated to the spectrum of scalars of the model.

hep-ph↗

arXiv2025

Three decades of FCNC studies in 3-3-1 model with right-handed neutrinos: from $Z^\prime$-dominance to the alignment limit

Flavor-changing neutral current (FCNC) processes play a prominent role in the search for physics beyond the Standard Model (SM) due to their sensitivity to new physics at the TeV scale. Meson-antimeson transitions and rare meson decays provide stringent constraints on new physics through precision measurements of observables such as mass differences, CP asymmetries, and branching ratios. Extensions of the SM based on the $\text{SU}(3)_C \times \text{SU}(3)_L \times \text{U}(1)_N$ gauge group offer a compelling framework for flavor physics, as FCNC processes emerge inexorably at tree level due to the non-universal transformations of the quark families. Among its various realizations, the version incorporating right-handed neutrinos (331RHN) is the most phenomenologically viable. This review synthesizes three decades of theoretical developments in FCNC phenomenology within the 331RHN model, from early $Z^\prime$-dominated studies to the recent recognition of the decisive role played by the SM-like Higgs boson and the identification of the alignment limit. We demonstrate that viable parameter space spans orders of magnitude, from $m_{Z^\prime} \sim$ a few hundred GeV to $\sim 100$ TeV, depending critically on quark mixing parametrizations and scalar alignment configurations, with significant implications for experimental searches at current and future colliders.

hep-ph↗

arXiv2025

Magnetic levitation by rotation described by a new type of Levitron

Recently, a novel magnetic levitation phenomenon involving two magnetically equivalent neodymium permanent magnets has been reported. In this work, we propose that this system functions as a scaled-up analog of the Levitron. The key distinction is that the ratio $m_/\mu_f$ becomes a function of the lateral displacement $\delta_R$, and magnetic trapping no longer depends on the rotational speed of the levitating body as in a conventional Levitron. Furthermore, we demonstrate that stable trapping occurs when a specific constraint on the $\delta_R$ parameter is satisfied, ensuring that the potential energy reaches a minimum at the equilibrium point.

physics.app-ph↗

arXiv2025

Meson Mixing Bounds on $Z^{\prime}$ Mass in the Alignment Limit: Establishing the Phenomenological Viability of the 331 Model

We perform a systematic study of flavor-changing neutral currents (FCNCs) in the 331 model with right-handed neutrinos (331RHNs), analyzing constraints on the $Z^\prime$ boson mass from $K$-, $D$-, $B_d$-, and $B_s$-meson oscillations. By explicitly incorporating scalar sector dynamics and quark rotation ambiguities ($V_L^{u,d}$), we demonstrate that $Z^\prime$ mass limits depend critically on the parametrization of Cabibbo-Kobayashi-Maskawa (CKM) matrix factors. Three scenarios are explored: (i) $V_L^u = V_\text{CKM}^\dagger$ (FCNCs restricted to $D$-mesons), (ii) $V_L^d = V_\text{CKM}$ (dominant $B_s$ constraints), and (iii) a hybrid mixing pattern. Strikingly, scenario (i) reduces the $Z^\prime$ mass bound to $M_{Z^\prime} \gtrsim 600\;\text{GeV}$-two orders of magnitude below literature values-by leveraging large experimental uncertainties in $D$-$\bar{D}$ oscillations. Conversely, scenario (ii) requires $M_{Z^\prime} \gtrsim 165\;\text{TeV}$ due to stringent $B_s$ data. We further establish the alignment limit $\cos(\phi+\varphi) = 0$ for the SM-like Higgs, showing its viability depends on $V_L^{u,d}$ configurations, with $B_s$ systems enforcing $|\cos(\phi+\varphi)| < 0.01$ in down-sector FCNC scenarios. Our analysis reveals that strategic choices of quark mixing matrices can suppress FCNC visibility, reconciling the 331 framework with flavor data without ultra-heavy $Z^\prime$ bosons. This work provides the first unified treatment of SM-like Higgs- and $Z^\prime$-mediated FCNCs in 331 models, identifying viable parameter spaces for collider phenomenology.

hep-ph↗

arXiv2024

Leptoquark-induced radiative masses for active and sterile neutrinos within the framework of the 3-3-1 model

In this work, we introduce the minimal set of leptoquarks into the 3-3-1 model with right-handed neutrinos, capable of generating radiative masses for active neutrinos. As a main consequence, the standard neutrinos acquire small Majorana masses at the one-loop level, while right-handed (sterile) neutrinos obtain small Majorana masses at the two-loop level, naturally making them light particles as well. Additionally, we discuss the viability of this scenario and several other interesting phenomenological consequences, including its impact on $B$-meson physics and rare Higgs decays, both of which are also induced by the leptoquarks.

hep-ph↗

arXiv2024

Exploring solutions to the muon g-2 anomaly in a 3-3-1 model under flavor constraints

The magnetic moment of the muon can receive significant two-loop contributions from a light pseudoscalar. Notably, the spectrum of scalars of 3-3-1 models include one pseudoscalar. However this scalar spectrum inevitably gives rise to flavor-changing neutral current (FCNC) processes. In this study, we examine, within the 3-3-1 model with right-handed neutrinos, whether such spectrum of scalars can account for the anomalous magnetic moment of the muon, considering the constraints imposed by $B$-meson decays, meson mixing, and invisible Higgs decays. Our principal finding reveals that a pseudoscalar with mass around 66 GeV and $\tan \beta =58$ can account for the $g-2$ anomaly without conflicting with flavor physics.

hep-ph↗

arXiv2024

Introducing scalar leptoquarks into a 3-3-1 model to solve the $(g-2)_\mu $ puzzle

In this work we introduce scalar leptoquarks into the 3-3-1 model with right-handed neutrinos with the aim of solving the $(g-2)_{\mu}$ puzzle. We show that besides the model supports leptoquarks in the octet, sextet, triplet and singlet representations, we identified that only one specif leptoquark in the singlet representation leads to flip of chirality as required to generate positive and robust contribution to the $(g-2)_\mu$. Then we calculate its contributions to $(g-2)_\mu$ and to the decay process $\mu \rightarrow e \gamma$ and discuss the results.

hep-ph↗

arXiv2023

Composite scalar bosons masses: Effective potential versus Bethe-Salpeter approach

Ten years ago the $125$ GeV Higgs resonance was discovered at the LHC[1,2], if this boson is a fundamental particle or a particle composed of new strongly interacting particles is still an open question. If this is a composite boson there are still no signals of other possible composite states of this scheme, a possible solution to this problem was recently discussed in Refs.[30,31], where it is argued that the Higgs boson can be a composite dilaton [30]. In this work, considering an effective potential for composite operators we verify that the potential responsible for a light composite scalar boson of $O(120)GeV$, behaves like $\propto \Phi^4$ suggesting that if the Higgs boson is a composite scalar it may be a composite dilaton.

hep-ph↗

arXiv2023

Evading the Landau pole in the minimal 3-3-1 model with leptoquarks

In its original version, the minimal 3-3-1 model possess a Landau-pole around 2-6 TeV scale. Current LHC bound on $Z^{\prime}$ implies that the $SU(3)_L\times U(1)_X$ symmetry must break spontaneously around 4 TeV which means that the model may lose its perturbative character even before symmetry breaking. This is a disaster for the model. Few attention has been devoted to this problem. Here we investigate the efficiency of scalar leptoquarks in evading or shifting the Landau pole to a harmless energy scale.

hep-ph↗

arXiv2022

Composite scalar boson mass dependence on the constituent mass anomalous dimension

We perform a Bethe-Salpeter equation (BSE) evaluation of composite scalar boson masses in order to verify how these masses can be smaller than the composition scale. The calculation is developed with a constituent self-energy dependent on its mass anomalous dimension ($\gamma$), and we obtain a relation showing how the scalar mass decreases as $\gamma$ is increased. We also discuss how fermionic corrections to the BSE kernel shall decrease the scalar mass, whose effect can be as important as the one of a large $\gamma$. An estimate of the top quark loop effect that must appear in the BSE calculation gives a lower bound on the composite scalar mass.

hep-ph↗

arXiv2021

Limit on Higgs boson trilinear self-coupling in coupled technicolor models

The trilinear self-coupling of the Higgs boson, in a theory in which this boson is composite, is compared to the experimental bound of this quantity obtained by the CMS experiment. In the case of a model where technicolor (TC) is coupled to QCD, we find that the experimental result already constrain the dynamics of the theory, which is represented by an expression of the technifermion self-energy ($\Sigma_{tc}$) typical of technicolor coupled models, and function of the dynamically generated technifermion mass and two other parameters that describe the technifermion dynamical mass momentum dependence. The limits imposed on this dynamics allow us to make a simple determination of pseudo-Goldstone boson masses that appear in these theories, indicating that these bosons may be expected to be quite massive.

hep-ph↗

arXiv2020

The mass splitting in an 331-TC coupled Scenario

The root of most of the technicolor (TC) problems lies in the way the ordinary fermions acquire their masses, where an ordinary fermion (f) couples to a technifermion (F) mediated by an Extended Technicolor (ETC) boson leading to fermion masses that vary with the ETC mass scale ($M_E$) as $1/M_E^2$. Recently, we discussed a new approach consisting of models where TC and QCD are coupled through a larger theory, in this case the solutions of these equations are modified compared to those of the isolated equations, and TC and QCD self-energies are of the Irregular form, which allows us to build models where ETC boson masses can be pushed to very high energies. In this work we extend these results for 331-TC models, in particular considering a coupled system of Schwinger-Dyson equations, we show that all technifermions of the model exhibit the same asymptotic behavior for TC self-energies. As an application we discuss how the mass splitting of the order $O(100)GeV$ could be generated between the second and third generation of fermions.

hep-ph↗

arXiv2020

Technicolor coupled models

When technicolor (TC), QCD, extended technicolor (ETC) and other interactions become coupled through their different Schwinger-Dyson equations, the solution of these equations are modified compared to those of the isolated equations. The change in the self-energies is similar to that obtained in the presence of four-fermion interactions, but without their ad hoc inclusion in the theory. In this case the TC and QCD self-energies decrease logarithmically with the momenta, which allows us to build models where ETC boson masses can be pushed to very high energies, and do not lead to undesirable flavor changing interactions. Viable TC models may be built along this line including a necessary horizontal symmetry. The different fermionic mass scales are dictated by the different strong interactions. Pseudo-Goldstone bosons acquire large masses in this class of models.

hep-ph↗

arXiv2019

Fermion mass splitting in the technicolor coupled scenario

We discuss fermion mass generation in unified models where QCD and technicolor (or any two strongly interacting theories) have their Schwinger-Dyson equations coupled. In this case the technicolor (TC) and QCD self-energies are modified in comparison with the behavior observed in the isolated theories. In these models the pseudo-Goldstone boson masses are much higher than the ones obtained in different contexts, and phenomenological signals, except from a light scalar composite boson, will be quite difficult to be observed at present collider energies. The most noticeable fact of these models is how the mass splitting between the different ordinary fermions is generated. We discuss how a necessary horizontal (or family) symmetry can be implemented in order to generate the mass splitting between fermions of different generations; how the fermionic mass spectrum may be modified due to GUT interactions, as well as how the mass splitting within the same fermionic generation are generated due to electroweak and GUT interactions.

hep-ph↗

arXiv2019

Technicolor models with coupled systems of Schwinger-Dyson equations

When Technicolor (TC), QCD, Extended Technicolor (ETC) and other interactions become coupled through their different Schwinger-Dyson equations, the solution of these equations are modified in comparison with the ones of the isolated equations. The change in the self-energies is similar to the one obtained in the presence of four-fermion interactions, but without their \textsl{ad hoc} inclusion in the theory. In this case TC and QCD self-energies decrease logarithmically with the momenta, what allow us to build models where ETC boson masses can be pushed to very high energies, and their effects will barely appear at present energies. Here we present a detailed discussion of this class of TC models. We first review the Schwinger-Dyson TC and QCD coupled equations, explaining the origin of the asymptotic self-energies. We develop the basic ideas of how viable TC models may be built along this line, where ordinary lepton masses appear naturally lighter than quark masses. One specific unified TC model associated with a necessary horizontal (or family) symmetry is described. The values of scalar and pseudo-Goldstone boson masses in this class of models are also discussed, as well as the value of the trilinear scalar coupling, and the consistency of the models with the experimental constraints.

hep-ph↗

arXiv2018

Schwinger-Dyson equation boundary conditions induced by ETC radiative corrections

The technicolor (TC) Schwinger-Dyson equations (SDE) should include radiative corrections induced by extended technicolor (ETC) interactions when TC is embedded into a larger theory including also QCD. These radiative corrections couple the different strongly interacting Dyson equations. We discuss how the boundary conditions of the coupled SDE system are modified by these corrections, and verify that the ultraviolet behavior of the self-energies are described by a function that decreases logarithmically with momentum.

hep-ph↗