arXiv subjects

A. Pérez Martínez

Publications and source records attributed to A. Pérez Martínez.

At least 19 recordsLinked to original sources

arXiv2026

Spontaneous CP breaking in $S_3$ flavored Higgs sector with soft-breaking terms

We analyze the Higgs sector of the minimal $S_3$-invariant extension of the Standard Model including spontaneous and explicit CP violation arising from the spontaneous electroweak symmetry breaking. This extended Higgs sector includes three SU(2) Higgs doublets with and without complex vev's, which ones providing an interesting scenario to analyze the Higgs masses spectrum, trilinear Higgs self-couplings and CP violation. We present how the spontaneous electroweak symmetry breaking coming from three SU(2) Higgs doublets gives an interesting scenario when spontaneous CP violation arises from the Higgs doublet $Φ_S$, singlet under $S_3$. Furthermore, a numerical analysis of the Higgs masses and trilinear Higgs self-couplings is presented. Particularly, we find a physical solution for the scenario in which spontaneous CP break is provided by $Φ_S$. The analysis of soft breaking to $S_3$ symmetry including CP breaking terms opens up a rich parameter space, with Higgs masses and trilinear Higgs self-couplings favoring one of the Higgs bosons as a SM-like type Higgs boson.

hep-ph↗

arXiv2024

Nonlinear electrodynamics for the vacuum of Dirac materials. Photon magnetic properties and radiation pressures

We investigate the magnetic properties of photons propagating through Dirac materials in a magnetic field, considering both vacuum and medium contributions. Photon propagation properties are obtained through a second-order expansion of non-linear Euler-Heisenberg electrodynamics at finite density and temperature considering Dirac material parameters (Dirac fine structure constant, band gap and Fermi velocity). Total magnetization (including electrons and photon contributions) and photon-effective magnetic moment are computed. Observables such as photon energy density, radiation pressure, and Poynting vector are obtained by an average of components of the energy-momentum tensor. All quantities are expressed in terms of Lagrangian derivatives. Those related to the vacuum are valid for any value of the external magnetic field, and both the weak and strong field limits are recovered. We discuss some ideas of experiments that may contribute to testing in Dirac materials the phenomenology of the strong magnetic field in the quantum electrodynamic vacuum and how non-linear corrections on the magnetization, radiation pressure, and birefringence, are amplified up to $10^3$ times QED corrections.

hep-th↗

arXiv2024

Magnetized Strange Stars and Signals of Gravitational Waves

We study the emission of gravitational waves from spheroidal magnetized strange stars for both an isolated slowly rotating star and a binary system. In the first case, we compute the quadrupole moment and the amplitude of gravitational waves that may be emitted. For the binary system, the tidal deformability is obtained by solving simultaneously the system of spheroidal structure equations and the Love number equation. These results are compared with the data inferred from the GW170817 event which is also used to calculate the mass and tidal deformability of the companion star in the binary system. Our model supports binary systems formed by magnetized strange stars describing reasonable signals of gravitational waves contrasted with other models of binary systems composed of magnetized hadronic stars and non-magnetized quark stars.

gr-qc↗

arXiv2023

Remarks on propagating waves in non-linear vacuum electrodynamics

Using the quadratic expansion in the photon fields of Euler-Heisenberg (EH) non-linear electrodynamics (NLED) Lagrangian model we study relevant vacuum properties in a scenario involving the propagation of a photon probe in the presence of a background constant and static magnetic field, ${\bf B_e}$. We compute the gauge invariant, symmetric and conserved energy-momentum tensor (EMT) and angular momentum tensor (AMT) for arbitrary magnetic field strength using the Hilbert method under the soft-photon approximation. We discuss how the presence of magneto-electric terms in the EH Lagrangian is a source of anisotropy, induce the non-zero trace in the EMT and leads to differences between EMT calculated by the Hilbert or Noether method. From the Hilbert EMT we analyze some quantities of interest such as the energy density, pressures, Poynting vector, and angular momentum vector, comparing and discussing the differences with respect to the improved Noether method. The magnetized vacuum properties are also studied showing that a photon effective magnetic moment can be defined for different polarization modes. The calculations are done in terms of derivatives of the two scalar invariants of electrodynamics, hence, extension to other NLED Lagrangian is straightforward. We discuss further physical implications and experimental strategies to test magnetization, photon pressure, and effective magnetic moment.

hep-ph↗

arXiv2022

Non-linear interaction of laser light with vacuum: contributions to the energy density and pressure in presence of an intense magnetic field

Recent simulations show that very large electric and magnetic fields near the kilo Tesla strength will likely be generated by ultra-intense lasers at existing facilities over distances of hundreds of microns in underdense plasmas. Stronger ones are even expected in the future although some technical dificulties must be overcome. In addition, it has been shown that vacuum exhibits a peculiar non-linear behaviour in presence of high magnetic and electric field strengths. In this work we are interested in the analysis of thermodynamical contributions of vacuum to the energy density and pressure when radiation interacts with it in the presence of an external magnetic field. Using the Euler-Heisenberg formalism in the regime of weak fields i.e. smaller than critical Quantum Electrodynamics field strength values, we evaluate these magnitudes and analyze the highly anisotropic behaviour we find. Our work has implications for photon-photon scattering with lasers and astrophysically magnetized underdense systems far outside their surface where matter effects are increasingly negligible.

physics.plasm-ph↗

arXiv2021

Magnetized vector boson gas at any temperature

We study the thermodynamic properties of a relativistic magnetized neutral vector boson gas at any temperature. By comparing the results with the low temperature and the non relativistic descriptions of this gas, we found that the fully relativistic case can be separated in two regimes according to temperature. For low temperatures, magnetic field effects dominate and the system shows a spontaneous magnetization, its pressure splits in two components and, eventually, a transversal magnetic collapse might occur. In the high temperature region, the gas behavior is led by pair production. The presence of antiparticles preserves the isotropy in the pressure, and increases the magnetization and the total pressure of the system by several orders. Astrophysical implications of those behaviors are discussed.

hep-ph↗

arXiv2019

The photon time delay in magnetized vacuum magnetosphere

We study the transverse propagation of photons in a magnetized vacuum considering radiative corrections in the one-loop approximation. The dispersion equation is modified due to the magnetized photon self-energy in the transparency region ($0<ω<2m_e$). The aim of our study is to explore propagation of photons in a neutron star magnetosphere (described by magnetized vacuum). The solution of the dispersion equation is obtained in terms of analytic functions. The larger the magnetic field, the lower the phase velocity and the more the dispersion curve deviates from the light-cone. For fixed values of the frequency, we study the dependence of photon time delay with the magnetic field strength, as well as with distance. For the latter, we adopt a magnetic dipole configuration and obtain that -- contrary to the expectation, according to the traditional time delay of photons in the interstellar medium -- photons of higher energy experience a longer time delay. A discussion of potential causes of this behaviour is presented.

astro-ph.HE↗

arXiv2019

Modeling anisotropic magnetized strange quark stars

Compact objects have an intrinsic anisotropy due to the presence of strong magnetic fields that cause considerable modifications on the equations of state (EoS). In this work, we study the impact of this anisotropy in the size and shape of magnetized strange quark stars using an axially symmetric metric in spherical coordinates, the gamma-metric. The results are compared with those obtained with the standard Tolman-Oppenheimer-Volkoff (TOV) equations for the parallel and perpendicular pressures independently. Differences in the results are discussed.

gr-qc↗

arXiv2019

Modeling anisotropic magnetized White Dwarfs with $γ$ metric

The effect of magnetic fields in the Equations of State (EoS) of compact objects is the splitting of the pressure in two components, one parallel and the other perpendicular to the magnetic field. This anisotropy suggests the necessity of using structure equations considering the axial symmetry of the magnetized system. In this work, we consider an axially symmetric metric in spherical coordinates, the $γ$-metric, and construct a system of equations to describe the structure of spheroidal compact objects. In addition, we connect the geometrical parameter $γ$ linked to the spheroid's radii, with the source of the anisotropy. So, the model relates the shape of the compact object to the physics that determines the properties of the composing matter. To illustrate how our structure equations work, we obtain the mass-radii solutions for magnetized White Dwarfs. Our results show that the main effect of the magnetic field anisotropy in White Dwarfs structure is to cause a deformation of these objects. Since this effect is only relevant at low densities, it does not affect the maximum values of magnetized White Dwarf's masses, which remain under Chandrasekhar limit.

astro-ph.HE↗

arXiv2018

(Self-)Magnetized Bose-Einstein Condensate stars

We study magnetic field effects on the Equations of State (EoS) and the structure of Bose-Einstein Condensate (BEC) stars, i.e. a compact object composed by a gas of interacting spin one bosons formed up by the pairing of two neutrons. To include the magnetic field in the thermodynamic description, we suppose that particle-magnetic field and particle-particle interactions are independent. We consider two configurations for the magnetic field: one where it constant and externally fixed, and another where it is produced by the bosons by self-magnetization. Since the magnetic field produces the splitting of pressures in the directions along and perpendicular to the magnetic axis, stable configurations of self-magnetized and magnetized BEC stars are studied using the recently found $γ$-structure equations that describe axially symmetric objects. The magnetized BEC stars are, in general spheroidal, less massive and smaller than the non-magnetic ones, being these effects more relevant at low densities. For the self-magnetized BEC stars their inner profiles of magnetic field can be computed as a function of the equatorial radii. The values obtained for the core and surface magnetic fields are in agreement with those typical of compact objects.

astro-ph.HE↗

arXiv2018

A non-relativistic magnetized vector boson gas at any temperature

We study the thermodynamic properties of a neutral vector boson gas in presence of a constant magnetic field, by means of a semi-classical approach that allows to introduce the spin in the non-relativistic spectrum of the bosons. Bose-Einstein condensation is obtained and it turns out to depend on all the parameters involved in the problem: temperature, particle density and magnetic field. An spontaneous magnetization appears at low temperature as a consequence of the condensed state. The axial symmetry imposed in the system by the magnetic field presence, splits the pressure in two components, one along and another perpendicular to the magnetic axis. Under certain conditions, the perpendicular pressure becomes negative signaling that the system undergoes a transversal magnetic collapse. The spontaneous magnetization might be useful to model magnetic field production inside compact stars, while the negative pressures imposes certain limits to the temperatures and densities needed inside these objects to support a given magnetic field.

cond-mat.quant-gas↗

arXiv2018

Kicks of magnetized strange quark stars induced by anisotropic emission of neutrinos

We study the anisotropic neutrino emission from the core of neutron stars induced by the star's magnetic field. We model the core as made out of a magnetized ideal gas of strange quark matter and implement the conditions for stellar equilibrium in this environment. The calculation is performed without resorting to analytical simplifications and for temperature, density and magnetic field values corresponding to typical conditions for a neutron star's evolution. The anisotropic neutrino emission produces a rocket effect that contributes to the star's kick velocity. We find that the computed values for the kick velocity lie within the range of the observed values, reaching velocities of the order of $\sim1000$ km s$^{-1}$ for magnetic fields between $10^{15}-10^{18}$ G and radii of 20 to 5 km, respectively.

astro-ph.HE↗

arXiv2018

Anisotropic equation of state of charged and neutral vector boson gases in a constant magnetic field. Astrophysical implications

We obtain the pressures and equations of state (EoS) of charged and neutral vector boson gases in a constant magnetic field. The axial symmetry imposed to the system by the field splits the pressures in the parallel and perpendicular directions along the magnetic axis, and this leads to anisotropic equations of state. The values of pressures and energy densities are in the order of those of Fermi gases in compact objects. This opens the possibility to the existence of magnetized boson stars. Under certain conditions, the perpendicular pressure might be negative imposing a bound to the stability of the star. Other implications of negative pressures are also discussed.

hep-ph↗

arXiv2017

Thermodynamical properties of a neutral vector boson gas in a constant magnetic field

The thermodynamical properties of a neutral vector boson gas in a constant magnetic field are studied starting from the spectrum given by Proca formalism. Bose Einstein Condensation (BEC) and magnetization are obtained, for the three and one dimensional cases, in the limit of low temperatures. In three dimensions the gas undergoes a phase transition to an usual BEC in which the critical temperature depends on the magnetic field. In one dimension a diffuse condensate appears as for the charged vector boson gas. In both cases, the condensation is reached not only by decreasing the temperature but also by increasing the magnetic field. In three and one dimensions self-magnetization is possible. The anisotropy in the pressures due to axial symmetry imposed to the system by the magnetic field is also discussed. The astrophysical implications are commented.

hep-ph↗

arXiv2016

Magnetized White Dwarfs

The purpose of this thesis is to obtain more realistic equations of state to describe the matter forming magnetized white dwarfs, and use them to solve its structure equations. The equations of state are determined by considering the weak magnetic field approximation $B<B_c$ ($B_c=4.41\times10^{13}\text{ G}$) for the electron gas of the star. The magnetic field introduces anisotropic pressures, even for the moderate values present in white dwarfs. Also, we consider the energy and pressure correction due to the Coulomb interaction of the electron gas with the ions located in a crystal lattice. Moreover, spherically symmetric Tolman-Oppenheimer-Volkoff structure equations are solved independently for the perpendicular and parallel pressures, confirming the necessity of using axisymmetric structure equations, more adequate to describe the anisotropic system. Therefore, we study the solutions in cylindrical coordinates. In this case, the mass per longitude unit is obtained instead of the total mass of the white dwarf.

astro-ph.HE↗

arXiv2015

A non-perturbative study of the evolution of cosmic magnetised sources

We undertake a hydrodynamical study of a mixture of tightly coupled primordial radiation, neutrinos, baryons, electrons and positrons, together with a gas of already decoupled dark matter WIMPS and an already existing "frozen" magnetic field in the infinite conductivity regime. Considering this cosmic fluid as the source of a homogeneous but anisotropic Bianchi I model, we describe its interaction with the magnetic field by means of suitable equations of state that are appropriate for the particle species of the mixture between the end of the leptonic era and the beginning of the radiation-dominated epoch. Fulfilment of observational bounds on the magnetic field intensity yields a "near FLRW" (but strictly non-perturbative) evolution of the geometric, kinematic and thermodynamical variables. This evolution is roughly comparable to the weak field approximation in linear perturbations on a spatially flat FLRW background of sources in which the frozen magnetic fields are coherent over very large supra-horizon scales. Our approach and results may provide interesting guidelines in potential situations in which non-perturbative methods are required to study the interaction between magnetic fields and the cosmic fluid.

gr-qc↗

arXiv2015

On propagation of photons in a magnetized medium

The aim of this work is to solve the dispersion relations near the first excitation threshold of photon propagating along the magnetic field in the strong field limit. We have calculated the time damping of the photon in two particular cases: the degenerate gas as well as the diluted gas limit being both important from the Astrophysical point of view. In particular the diluted gas limit could describe the magnethosphere of neutron stars. The solutions have been used to obtain a finite Quantum Faraday angle in both limits. A resonant behavior for the Faraday angle is also obtained. To reproduce the semi-classical result for the Faraday rotation angle the weak field limit is considered.

astro-ph.HE↗

arXiv2013

Anomalous-Magnetic-Moment Effects in a Strongly Magnetized and Dense Medium

We investigate the quantum corrections of the anomalous magnetic moment (AMM) for fermions in the presence of a strong magnetic field using the Ritus's approach. At strong fields the particles get different AMM's depending on the LL's. This result is different from what is obtained with the Schwinger's approximation at weak field where the AMM is independent of the LL. We analyze the significance of the AMM contribution to the Equation of State (EoS) of the magnetized system, in the weak and strong field approximations.

nucl-th↗