SearcharxivSearch

arXiv subjects

M. C. Rodriguez

Publications and source records attributed to M. C. Rodriguez.

At least 19 recordsLinked to original sources

Classification of $g$-modes for neutron stars with a strong transition: Novel universal relation including slow stable hybrid stars

We investigate the behavior of the non-radial gravity-pulsation discontinuity $g$-mode in neutron stars with a strong first-order phase transition which give rise to hybrid-star configurations. These modes are of utmost relevance since they can be potentially excited in isolated as well as binary neutron star systems in the inspiral phase, thus allowing us to indirectly detect the presence of a deconfinement transition. In order to do this, we consider four categories of hybrid stars that present distinctive features in their equations of state. We employ the constant speed of sound parametrization, which accounts for a sharp phase transition between confined hadronic matter and deconfined quark matter. Then, working within the relativistic Cowling approximation to obtain the frequencies of non-radial oscillations, we find that, depending on the hybrid star category, the relations between discontinuity $g$-mode frequencies and masses as well as tidal deformabilities display a highly distinct behavior across the diverse hybrid star categories that appear in the slow hadron-quark conversion regime. This distinct phenomenology provides smoking-gun evidence to clearly distinguish and further classify hybrid stars with a strong transition from purely hadronic stars using upcoming gravitational-wave data. In addition, we present for each of the categories studied the relation between the $g$-mode frequency and the normalized energy density jump. Finally, we present a novel universal relation for the discontinuity $g$-mode able to encompass the four categories including long branches of slow stable hybrid stars and address its asteroseismological capability.

hep-ph

The Masses of Fermions in the context of the Supersymmetric $SU(3)_{C}\times SU(3)_{L}\times U(1)_{N}$ Model

We will study in details the masses spectrum of fermions of the Minimal Supersymmetric $SU(3)_{C}\times SU(3)_{L}\times U(1)_{N}$ Model. We will consider the case in which all the usual neutral scalars fields of this model obtain vacuum expectation values, in both case when we have $R$-parity conservation, respect the invariance of the quantum number, ${\cal F}\equiv B+L$, where $B$ is the baryon number while $L$ is the total lepton number, and the oppposite ones, it means $R$-parity violation. We will present numerical predictions for all the fermions of this model, we will show that all masses and mixing angles are in agreement with current experimental data.

hep-ph

Spontaneous breaking of a global symmetry in the Minimum Supersymmetric $SU(3)_{C}\times SU(3)_{L}\times U(1)_{N}$ Model

We present a preliminar study of the scalar potential of the usual scalars in the Minimal Supersymmetric $SU(3)_{C}\times SU(3)_{L}\times U(1)_{N}$ Model. We will consider the case in which all the usual neutral scalars fields of this model obtain vacuum expectation values. When we allow in our superpotential, only interactions that respect the invariance of the quantum number, ${\cal F}\equiv B+L$, where $B$ is the baryon number while $L$ is the total lepton number. We obtain, as in the minimal $SU(3)_{C}\times SU(3)_{L}\times U(1)_{N}$ model without supersymmetry, a Majoron. However, by allowing the violation of this quantum number, we can remove the Majoron in a mechanism similar to that recently presented in the Supersymmetric version of the scheme of Gelmini-Roncadelli. The mass spectrum obtained is in agreement with current experimental data.

hep-ph

Gauge bosons masses in the context of the Supersymmetric $SU(3)_{C}\otimes SU(3)_{L}\otimes U(1)_{N}$ Model

In this article, we present a detailed study of the masses of all gauge bosons, as well as explaing recent experimental data regarding the $W$-boson mass presented by the CDF collaboration and even possible changes that these data can bring to experimental measurements of the masses of $Z$-boson mass in the context of the Minimal Supersymmetric $SU(3)_{C}\otimes SU(3)_{L}\otimes U(1)_{N}$ Model. We also intend to show a phenomenological analysis of possible mixtures of gauge bosons in this model. We will show that our numerical predictions for the masses of the physical gauge bosons are within the current experimental limits.

hep-ph

Three approaches for the classification of protoneutron star oscillation modes

The future detection of gravitational waves (GWs) from a galactic core-collapse supernova will provide information on the physics inside protoneutron stars (PNS). In this work, we apply three different classification methods for the PNS non-radial oscillation modes: Cowling classification, Generalized Cowling Nomenclature (GCN), and a Classification Based on Modal Properties (CBMP). Using PNS models from $3$D simulations of core-collapse supernovae, we find that in the early stages of the PNS evolution, typically before $0.4$ seconds after the bounce, the Cowling classification is inconsistent, but the GCN and the CBMP provide complementary information that helps to understand the evolution of the modes. In the GCN, we note several avoided crossings as the mode frequencies evolve at early times, while the CBMP tracks the modes across the avoided crossings. We verify that the strongest emission of GWs by the PNS corresponds to the $f$-mode in the GCN, indicating that the mode trapping region alternates between the core and the envelope at each avoided crossing. At later times, approximately $0.4$ seconds after the bounce, the three classification methods present a similar description of the mode spectrum. We use our results to test universal relations for the PNS modes according to their classification and find that the behaviour of the universal relations for $f$- and $p$-modes is remarkably simple in the CBMP.

astro-ph.HE

The Scalar Potential of Supersymmetric $SU(3)_{C}\times SU(3)_{L}\times U(1)_{N}$ Model

We will study in details the full scalar potential of the Minimal Supersymmetric $SU(3)_{C}\times SU(3)_{L}\times U(1)_{N}$ Model. We will present numerical predictions for all the usual scalars of this model, we will show that the mass of the light scalar of CP par is $125.5$ GeV, such that its masses satisfy the current experimental constraints.

hep-ph

The Minimal Supersymmetric Universal Seesaw Mechanism (MSUSM)

We build a supersymmetric model with $SU(2)_{L}\otimes SU(2)_{R}\otimes U(1)_{(B-L)}$ electroweak gauge symmetry, where $SU(2)_{L}$ is the left-handed currents while $SU(2)_{R}$ is the right-handed currents and $B$ and $L$ are the usual baryonic and leptonic numbers. We can generate an universal seesaw mechanism to get masses for all the usual fermions in this model, it means quarks and leptons, and also explain the mixing experimental data. We will also to study the masses of the Gauge Bosons and also the masses of all usual scalars of this model.

hep-ph

Hybrid stars with sequential phase transitions: the emergence of the g$_2$ mode

Neutron stars are the densest objects in the Universe, with $M \sim 1.4 M_{\odot}$ and $R \sim 12$ km, and the equation of state associated to their internal composition is still unknown. The extreme conditions to which matter is subjected inside neutron stars could lead to a phase transition in their inner cores, giving rise to a hybrid compact object. The observation of $2M_{\odot}$ binary pulsars (PSR~J1614-2230, PSR~J0343$+$0432 and PSR~J0740$+$6620) strongly constraints theoretical models of the equation of state. Moreover, the detection of gravitational waves emitted during the binary neutron star merger, GW170817, and its electromagnetic counterpart, GRB170817A, impose additional constraints on the tidal deformability. In this work, we investigate hybrid stars with sequential phase transitions hadron-quark-quark in their cores. We assume that both phase transitions are sharp and analyse the rapid and slow phase conversion scenarios. For the outer core, we use modern hadronic equations of state. For the inner core we employ the constant speed of sound parametrization for quark matter. We analyze more than 3000 hybrid equations of state, taking into account the recent observational constraints from neutron stars. The effects of hadron-quark-quark phase transitions on the normal oscillation modes $f$ and $g$, are studied under the Cowling relativistic approximation. Our results show that, in the slow conversion regime, a second quark-quark phase transition gives rise to a new $g_2$~mode. We discuss the observational implications of our results associated to the gravitational waves detection and the possibility of detecting hints of sequential phase transitions and the associated $g_2$~mode.

astro-ph.HE

The Supersymmetric $(B-L)$ model with three non-identical right-handed neutrinos

We build a supersymmetric version with $SU(3)_{C}\otimes SU(2)_{L}\otimes U(1)_{Y^{\prime}}\otimes U(1)_{(B-L)}$ gauge symmetry, where $Y^{\prime}$ is a new charge and ($B$) and ($L$) are the usual baryonic and leptonic numbers, respectivelly. The model has three right-handed neutrinos with non identical $(B-L)$ charges. We will use the superfield formalism in order to build our lagrangian and it is possible to accommodate all fermion masses at the tree level. In particular, the type-I seesaw mechanism is implemented for the generation of the active neutrino masses and also explain the mixing angle at the fermion sector. There are good candidates to Dark Matter, it can be the lighest righ-handed neutrinos or lighest right-handed sneutrinos or the lighest usual scalar field and due a Majorana phase at sneutrinos right-handed masses, it can induce Leptogenesis in this model.

hep-ph

Scotogenic model with $B - L$ symmetry and exotic neutrinos

We consider a model with three Higgs doublet in a discrete $B - L\times \mathbb{Z}_3$ discrete symmetries. Two of the scalar doublets are inert due to the $\mathbb{Z}_3$ symmetry. We calculated all the mass spectra in the scalar and lepton sectors and accommodate the leptonic mixing matrix as well.

hep-ph

Radiative neutrino masses and exotic right-handed neutrinos

We consider an extension of the standard electroweak model with three Higgs doublets and global $B-L$ and $\mathbb{Z}_2$ symmetries. Two of the scalar doublets are inert due to the $\mathbb{Z}_2$ symmetry. We calculated all the mass spectra in the scalar and lepton sectors and accommodate the leptonic mixing matrix as well. We also include an analysis of the scalar sector, showing that the potential is limited from below, and we obtain the masses of the scalar sector. Furthermore we consider the effects of the model on the anaomalous magnetic dipole of charged leptons and the $μ\to eγ$ decay. We also present the SUSY version of the model with global $B-L$.

hep-ph

Short review about the MSSM with three right-handed neutrinos (MSSM3RHN)

We give a review about the Minimal Supersymmetric Standard Model with three right-handed neutrinos (MSSM3RHN). We, first introduce the minimal set of fields to built this model in their superfields formalism. After it, we build the lagrangian of the model in the superspace formalism and also introduce the soft terms to break SUSY. We show how to get masses to the neutrinos and sneutrinos in this model.

hep-ph