arXiv subjects

Manoel M. Ferreira Jr

Publications and source records attributed to Manoel M. Ferreira Jr.

At least 37 records · Page 2Linked to original sources

arXiv2020

Constraining EDM and MDM lepton dimension five interactions in the electroweak sector

We investigate dimension five Lorentz-violating nonminimal interactions in the electroweak sector, in connection with the possible generation of electric dipole moment (EDM), weak electric dipole moment (WEDM), magnetic dipole moment (MDM) and weak magnetic dipole moment (WMDM) for leptons. These couplings are composed of the physical fields and LV tensors of ranks ranging from 1 to 4. The CPT-odd couplings do no generate EDM\ behavior and do not provide the correct MDM\ signature, while the CPT-even ones yield EDM and MDM\ behavior, being subject to improved constraining. Tau lepton experimental data is used to constrain the WEDM\ and WMDM couplings to the level of $10^{-4}\left( \text{GeV}\right) ^{-1},$ whereas electron MDM and EDM data is employed to improve constraints to the level of $10^{-17}\left( \text{GeV}\right) ^{-1}$ and $10^{-11}\left( \text{GeV}\right) ^{-1},$ respectively.

hep-ph↗

arXiv2019

Constraining Dimension-Six Nonminimal Lorentz-Violating Electron--Nucleon Interactions with EDM Physics [CPT'19]

Electric dipole moments of atoms can arise from P-odd and T-odd electron--nucleon couplings. This work studies a general class of dimension-six electron--nucleon interactions mediated by Lorentz-violating tensors of ranks ranging from $1$ to $4$. The possible couplings are listed as well as their behavior under C, P, and T, allowing us to select the couplings compatible with electric-dipole-moment physics. The unsuppressed contributions of these couplings to the atom's hamiltonian can be read as equivalent to an electric dipole moment. The Lorentz-violating coefficients' magnitudes are limited using electric-dipole-moment measurements at the levels of $3.2\times10^{-31}\text{(eV)}^{-2}$ or $1.6\times10^{-33}\text{(eV)}^{-2}$.

hep-ph↗

arXiv2019

Constraining dimension-six nonminimal Lorentz-violating electron-nucleon interactions with EDM physics

The electric dipole moment (EDM) of an atom could arise also from $P$-odd and $T$-odd electron-nucleon couplings. In this work we investigate a general class of dimension-$6$ electron-nucleon ($e$-$N$) nonminimal interactions mediated by Lorentz-violating (LV) tensors of rank ranging from $1$ to $4$. The possible couplings are listed as well as their behavior under $C$, $P$ and $T$, allowing us to select the couplings compatible with EDM physics. The unsuppressed contributions of these couplings to the atom's Hamiltonian can be read as EDM-equivalent. The LV coefficients' magnitudes are limited using EDM experimental data to the level of $3.2\times 10^{-13} \text{(GeV)}^{-2}$ or $1.6\times10^{-15} \text{(GeV)}^{-2}$.

hep-ph↗

arXiv2019

A dimension five Lorentz-violating nonminimal coupling for mesons in the KLZ model

We investigate a dimension five Lorentz-violating (LV) nonminimal coupling between the neutral vector meson field strength and the pion current in the context of the Kroll-Lee-Zumino (KLZ) model. In this modified model we study the vector meson dominance (VMD) through of the imposing of new universality conditions between the couplings that comes from LV contributions. We also show that the LV nonminimal coupling leads to a linear momentum dependence in the timelike pion form factor, that is used to evaluate LV corrections for the muon anomalous magnetic moment. The experimental imprecision of such quantity allows us to obtain upper bound $\bar{g}ξ_{0} < 1.0 \mathbf{~}\mathrm{GeV}^{-1}.$ In addition, we also use the LV nonminimal coupling in the KLZ model to recalculate the $ρ$ decay rate. In this case the experimental imprecision is used to constrain the magnitude of the LV parameter at the level of $\bar{g}ξ_{0} < 1.9\times10^{-2}\mathbf{~}\mathrm{GeV}^{-1}$.

hep-ph↗

arXiv2018

Relativistic motion under constant force: velocity and acceleration behavior

In relativistic dynamics, force and acceleration are no longer parallel. In this article, we revisit the relativistic motion of a particle under the action of a constant force, $\boldsymbol{f}$. \ For a two-dimensional motion, the final velocity in each axis is $(f_{i}/f)c,$ independently of the initial velocities, yielding an asymptotic velocity always parallel to the force. The particular case in which the force is applied in a single axis is analyzed in detail, with the behavior of velocity and acceleration being exhibited for several configurations. Some previous results of the literature concerning velocity and acceleration behavior are improved and better explored. Differently from which was previously claimed, it is shown that a negative acceleration component can exist in the direction of the biggest force component and that acceleration does not decrease monotonically to zero.

physics.class-ph↗

arXiv2018

Lorentz-violating contributions to the nuclear Schiff moment and nuclear EDM

In the context of an atom endowed with nuclear electric dipole moment (EDM), we consider the effects on the Schiff moment of $CPT$-even Lorentz-violating (LV) terms that modify the Coulomb potential. First, we study the modifications on the Schiff moment when the nucleus interacts with the electronic cloud by means of a Coulomb potential altered only by the $P$-even LV components. Next, by supposing the existence of an additional intrinsic LV EDM generated by other LV sources, we assess the corrections to the Schiff moment when the interaction nucleus-electrons runs mediated by a Coulomb potential modified by both the $P$-odd and $P$-even LV components. We then use known estimates and EDM measurements to discuss upper bounds on the new Schiff moment components and the possibility of an intrisic nuclear EDM component ascribed to LV effects.

hep-ph↗

arXiv2016

Constraining CPT-odd nonminimal interactions in the Electroweak sector

In this work, we propose two possibilities of CPT-odd and Lorentz-violating (LV) nonminimal couplings in the Electroweak sector. These terms are gauge-invariant and couple a fixed 4-vector to the physical fields of the theory. After determining the LV contributions to the electroweak currents, we reassess the evaluation of the decay rate for the vector mediators $W$ and $Z$. Using the experimental uncertainty in these decay rates, upper bounds of $1$ part in $10^{-15}$ (eV )$^{-1}$ and $10^{-14}$ (eV )$^{-1}$ are imposed on the magnitude of the proposed nonmimal interactions.

hep-ph↗

arXiv2016

General CPT-even dimension-five nonminimal couplings between fermions and photons yielding EDM and MDM

In this letter, we examine a new class of CPT-even nonminimal interactions, between fermions and photons, deprived of higher order derivatives, that yields electric dipole moment (EDM) and magnetic dipole moment (MDM) in the context of the Dirac equation. The couplings are dimension-five CPT-even and Lorentz-violating nonminimal structures, composed of a rank-2 tensor, $T_{μν}$, the electromagnetic tensor, and gamma matrices, being addressed in its axial and non-axial Hermitian versions, and also comprising general possibilities. We then use the electron's anomalous magnetic dipole moment and electron electric dipole moment measurements to reach upper bounds of $1$ part in $10^{20}$ and $10^{25}$ (eV )$^{-1}$.

hep-ph↗

arXiv2015

Constraining CPT-even and Lorentz-violating nonminimal couplings with the electron magnetic and electric dipole moments

We analyse some dimension-five CPT-even and Lorentz-violating nonminimal couplings between fermionic and gauge fields in the context of the Dirac equation. After evaluating the nonrelativistic Hamiltonian, we discuss the behavior of the terms under discrete symmetries and analyse the implied effects. We then use the anomalous magnetic dipole moment and electron electric dipole moment measurements to reach upper bounds of $1$ part in $10^{20}$ and $10^{24}$ $\left( eV\right) ^{-1}$, improving the level of restriction on such couplings by at least 8 orders of magnitude. These upper bounds are also transferred to the Sun-centered frame by considering the Earth's rotational motion.

hep-ph↗

arXiv2012

Consistency analysis of a nonbirefringent Lorentz-violating planar model

In this work analyze the physical consistency of a nonbirefringent Lorentz-violating planar model via the analysis of the pole structure of its Feynman propagators. The nonbirefringent planar model, obtained from the dimensional reduction of the CPT-even gauge sector of the standard model extension, is composed of a gauge and a scalar fields, being affected by Lorentz-violating (LIV) coefficients encoded in the symmetric tensor $κ_{μν}$. The propagator of the gauge field is explicitly evaluated and expressed in terms of linear independent symmetric tensors, presenting only one physical mode. The same holds for the scalar propagator. A consistency analysis is performed based on the poles of the propagators. The isotropic parity-even sector is stable, causal and unitary mode for $0\leqκ_{00}<1$. On the other hand, the anisotropic sector is stable and unitary but in general noncausal. Finally, it is shown that this planar model interacting with a $λ|φ|^{4}-$Higgs field supports compactlike vortex configurations.

hep-th↗

arXiv2011

Aspects of a planar nonbirefringent and CPT-even electrodynamics stemming from the Standard Model Extension

We have studied a (1+2)-dimensional Lorentz-violating model which is obtained from the dimensional reduction of the nonbirefringent sector of the CPT-even electrodynamics of the standard model extension (SME). The planar theory contains a gauge sector and a scalar sector which are linearly coupled by means of a Lorentz-invariance violating (LIV) vector, $S^μ$, while the kinetic terms of both sectors are affected by the components of a Lorentz-violating symmetric tensor, $κ^{μν}$. The energy-momentum tensor reveals that both sectors present energy stability for sufficiently small values of the Lorentz-violating parameters. The full dispersion relation equations are exactly determined and analyzed for some special configurations of the LIV backgrounds, showing that the planar model is entirely nonbirefringent at any order in the LIV parameters. At first order, the gauge and scalar sectors are described by the same dispersion relations. Finally, the equations of motion have been solved in the stationary regime and at first order in the LIV parameters. It is observed that the Lorentz-violating parameters do not alter the asymptotical behavior of the electric and magnetic fields but induce an angular dependence which is not present in Maxwell's planar theory.

hep-th↗

arXiv2011

Dimensional reduction of the CPT-even electromagnetic sector of the Standard Model Extension

The CPT-even abelian gauge sector of the Standard Model Extension is represented by the Maxwell term supplemented by $(K_{F})_{μνρσ}F^{μν}F^{ρσ}$, where the Lorentz-violating background tensor, $(K_{F})_{μνρσ}$, possesses the symmetries of the Riemann tensor. In the present work, we examine the planar version of this theory, obtained by means of a typical dimensional reduction procedure to $(1+2)$ dimensions. The resulting planar electrodynamics is composed of a gauge sector containing six Lorentz-violating coefficients, a scalar field endowed with a noncanonical kinetic term, and a coupling term that links the scalar and gauge sectors. The dispersion relation is exactly determined, revealing that the six parameters related to the pure electromagnetic sector do not yield birefringence at any order. In this model, the birefringence may appear only as a second order effect associated with the coupling tensor linking the gauge and scalar sectors.The equations of motion are written and solved in the stationary regime. The Lorentz-violating parameters do not alter the asymptotic behavior of the fields but induce an angular dependence not observed in the Maxwell planar theory.

hep-th↗

arXiv2010

Feynman propagator for the nonbirefringent CPT-even electrodynamics of the Standard Model Extension

The CPT-even gauge sector of the Standard Model Extension is composed of nineteen components comprised in the tensor $(K_{F})_{μνρσ}$, of \ which nine do not yield birefringence. In this work, we examine the Maxwell electrodynamics supplemented by these nine nonbirefringent CPT-even components in aspects related to the Feynman propagator and full consistency (stability, causality, unitarity). We adopt a prescription that parametrizes the nonbirefringent components in terms of a symmetric and traceless tensor, $K_{μν},$ and second parametrization that writes $K_{μν}$ in terms of two arbitrary four-vectors, $U_μ$ and $V_ν.$ We then explicitly evaluate the gauge propagator of this electrodynamics in a tensor closed way. In the sequel, we show that this propagator and involved dispersion relations can be specialized for the parity-odd\ and parity-even sectors of the tensor $(K_{F})_{μνρσ}$. In this way, we reassess some results of the literature and derive some new outcomes showing that the parity-even anisotropic sector engenders a stable, noncausal and unitary electrodynamics.

hep-th↗

arXiv2010

Gauge propagator and physical consistency of the CPT-even part of the Standard Model Extension

In this work, we explicitly evaluate the gauge propagator of the Maxwell theory supplemented by the CPT-even term of the SME. First, we specialize our evaluation for the parity-odd sector of the tensor $W_{μνρσ}$,\ using a parametrization that retains only the three nonbirefringent coefficients. From the poles of the propagator, it is shown that physical modes of this electrodynamics are stable, non-causal and unitary. In the sequel, we carry out the parity-even gauge propagator using a parametrization that allows to work with only the isotropic nonbirefringent element. In this case, we show that the physical modes of the parity-even sector of the tensor $W$ are causal, stable and unitary for a limited range of the isotropic coefficient.

hep-th↗

arXiv2009

Parity-odd and CPT-even electrodynamics of the SME at Finite Temperature

This work examines the finite temperature properties of the CPT-even and parity-odd electrodynamics of the standard model extension. We start from the partition function written into the functional integral formalism in Ref. \cite{Finite}. After specializing the Lorentz-violating tensor $ W_{ανρφ}$ for the nonbirefringent and parity-odd coefficients, the partition function is explicitly carry out, showing that it is a power of the Maxwell's partition function. Also, it is observed that the LIV coefficients induce an anisotropy in the black body angular energy density distribution. The Planck's radiation law retains its usual frequency dependence and the Stefan-Boltzmann law keeps the same form, except for a global proportionality constant.

hep-th↗

arXiv2009

Finite Temperature behavior of the CPT-even and parity-even electrodynamics of the Standard Model Extension

In this work, we examine the finite temperature properties of the CPT-even and Lorentz-invariance-violating (LIV) electrodynamics of the standard model extension, represented by the term $W_{ανρϕ}F^{αν}F^{ρϕ}$. We begin analyzing the hamiltonian structure following the Dirac's procedure for constrained systems and construct a well-defined and gauge invariant partition function in the functional integral formalism. Next, we specialize for the non-birefringent coefficients of the tensor $W_{ανρϕ}$. In the sequel, the partition function is explicitly carried out for the parity-even sector of the tensor $W_{ανρϕ}$. The modified partition function is a power of the Maxwell's partition function. It is observed that the LIV coefficients induce an anisotropy in the black body angular energy density distribution. The Planck's radiation law, however, retains its frequency dependence and the Stefan-Boltzmann law keeps the usual form, except for a change in the Stefan-Boltzmann constant by a factor containing the LIV contributions.

hep-th↗

arXiv2009

Stationary solutions for the parity-even sector of the CPT-even and Lorentz-covariance-violating term of the standard model extension

In this work, we focus on some properties of the parity-even sector of the CPT-even electrodynamics of the standard model extension. We analyze how the six non-birefringent terms belonging to this sector modify the static and stationary classical solutions of the usual Maxwell theory. We observe that the parity-even terms do not couple the electric and magnetic sectors (at least in the stationary regime). The Green's method is used to obtain solutions for the field strengths E and B at first order in the Lorentz- covariance-violating parameters. Explicit solutions are attained for point-like and spatially extended sources, for which a dipolar expansion is achieved. Finally, it is presented an Earth-based experiment that can lead (in principle) to an upper bound on the anisotropic coefficients as stringent as $(\widetildeκ_{e-}) ^{ij}<2.9\times10^{-20}.$

hep-th↗

arXiv2008

Classical solutions for the Carroll-Field-Jackiw-Proca electrodynamics

In the present work, we investigate classical solutions of the Maxwell-Carroll-Field-Jackiw-Proca (MCFJP) electrodynamics for the cases a purely timelike and spacelike Lorentz-violating (LV) background. Starting from the MCFJP Lagrangian and the associated wave equations written for the potential four-vector, the tensor form of the Green function is achieved. In the timelike case, the components of the stationary Green function are explicitly written. The classical solutions for the electric and magnetic field strengths are then evaluated, being observed that the electric sector is not modified by the LV background, keeping the Maxwell-Proca behavior. The magnetic field associated with a charge in uniform motion presents an oscillating behavior that also provides an oscillating MCFJ solution (in the limit of a vanishing Proca mass), but does not recover the Maxwell-Proca solution in the limit of vanishing background. In the spacelike case, the stationary Green function is written and also explicitly carried out in the regime of a small background. The electric and magnetic fields reveal to possess an exponentially decaying behavior, that recover the Maxwell-Proca solutions.

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