arXiv subjects

S. Gómez-Ávila

Publications and source records attributed to S. Gómez-Ávila.

5 recordsLinked to original sources

arXiv2025

Wave equations for spin 3/2 quantum fields

In this work, we review formulations of wave equations for spin-3/2 fields constructed from different Lorentz group representations. We analyze the Joss-Weinberg single-spin chiral representation and the double-spin chiral representation, focusing on the structure of their covariant operators. We explore the Duffin-Kemmer-Petiau (DKP) formalism and its algebraic properties, originally introduced for spin--0 and spin-1 particles, and here considered as a potential framework for spin 3/2. As a result, we recover the well-known Rarita-Schwinger representation and we find a new possibility in the $(3/2,0) \oplus (0,3/2) \oplus (1,1/2) \oplus (1/2,1)$ representation.

hep-th↗

arXiv2025

Effective textures from a $[SU(3)]^3$ flavored scalar sector

Current constraints on flavor-changing neutral currents (FCNCs) strongly indicate that any new physics emerging at the 1-10 TeV scale must adhere to the Minimal Flavor Violation (MFV) principle, where Yukawa couplings are the sole sources of flavor violation. In this work, we present a model inspired by a gauged $SU(3)$ flavor symmetry that dynamically generates leptonic Yukawa matrices through effective operators. The model incorporates a scalar sector with two sets of flavons, characterized by their vacuum expectation values (VEVs), which govern the suppression scale of the Yukawa couplings and the hierarchy of neutrino masses. By leveraging phenomenologically viable Yukawa textures, we derive restrictions on the flavon VEVs and demonstrate the compatibility of the model with experimental neutrino oscillation data. Furthermore, the model predicts at least one neutrino mass to be strongly suppressed, consistent with the normal mass ordering and experimental upper bounds. This framework provides a robust mechanism for dynamically generating neutrino masses and mixing while addressing key challenges in leptonic flavor physics, such as FCNC suppression and CP-violating phases.

hep-ph↗

arXiv2021

2-zeroes texture and the Universal Texture Constraint

Texture matrices are a way of mitigating the redundancy inherent in the description of flavor physics via Yukawa couplings by eliminating some entries in order to identify relevant parameters. A four-zero texture scheme has been used in the literature to successfully describe fermion masses and mixing. However, as we show in this work, improving experimental constraints require an update to this analysis. In this paper the implications of a 2-zero texture mass matrix is studied for quarks and leptons. We show that the introduction of a new parameter in each mass matrix allow us to reach good results with relative low cost in predictability. We report a numerical study using a hybridized nature-inspired/cellular automata search algorithm. We find that leptons and quarks can be described by the same 1-zero structure. We describe some scenarios where a simplified description can be achieved, including a narrow region in parameter space where the same values describe charged leptons and neutrinos, which is a stronger version of a previously proposed Universal Texture Constraint.

hep-ph↗

arXiv2020

On the Universal Texture in the PA-2HDM for the V-SPIN case

In a Partially Aligned Two Higgs Doublet Model, where only is allowed flavor violation between third and second generation of fermions, we propose a mechanism to generate the second Yukawa matrix through a Unitary V-Spin flavor transformation on the mass matrix for quarks and leptons. Also we assume that this flavor transformation is universal, this is, we use the same parameters to generate Yukawa matrix elements in both sectors, reducing drastically the number of free parameters. As consequence we obtained a serie of relations between Yukawa matrix elements, that we called the Universality Constraint. Also, we obtained an interval of values for the second Yukawa matrix elements, expressed in terms of the Cheng and Sher ansatz, for $τ\to\ muμ^+μ^-$ and $τ\toγμ$ coming from the Universality Constraint and experimental bounds for light scalar masses. Finally, we show the allowed region of parameters for the flavor transformation from $B_s\toμμ$ decays, $B_s^0-\bar{B}_s^0$ mixing, $τ\toμμ^+μ^-$ and $τ\toγμ$ experimental bounds.

hep-ph↗

arXiv2019

Phenomenology of the Partially Aligned 2HDM with leptonic decay of mesons

In this paper we present a phenomenological analysis of the Partially Aligned Two Higgs Doublet Model (PA-2HDM) by using leptonic decays of mesons and $B^0_{d,s}$-$\bar B^0_{d,s}$ mixing. We focus our attention in a scenario where the leading contribution to FCNC is given by the tree level interaction with the light pseudoscalar $A^0$ ($M_{A^0}\sim 250$ GeV). We show how an underlying flavor symmetry controls FCNC in the quark and lepton couplings with the pseudoscalar, without alignment between Yukawa matrices. Upper bounds on the free parameters are calculated in the context of the leptonic decays $B^0_{s,d}\toμ^+μ^-$ and $K^0_L\to μ^+μ^-$ and $B^0_{s,d}$ mixing. Also, our assumptions implies that bounds on New Physics contribution in the quark sector coming from $B^0_{s,d}$ mixing impose an upper bound on the parameters for the leptonic sector. Finally we give predictions of branching ratios for leptonic decay of mesons with FCNC and LFV.

hep-ph↗