Accidental symmetries and massless quarks in the economical 331 model
Abstract
In the framework of a 331 model with a minimal scalar sector, known as the economical 331 model, we study its capabilities of generating realistic quark masses. After a detailed study of the symmetries of the model, before and after the spontaneous symmetry breaking, we find a remaining axial symmetry that prevents some quarks from gaining mass at all orders in perturbation theory. Since this accidental symmetry is anomalous, we also consider briefly the possibility of generating their masses for nonperturbative effects. However, we find that nonperturbative effects are not enough to generate the measured masses for the three massless quarks. Hence, these results imply that the economical 331 model is not a realistic description of the electroweak interaction.
 Authors:
 Publication Date:
 Research Org.:
 Argonne National Lab. (ANL), Argonne, IL (United States)
 Sponsoring Org.:
 USDOE Office of Science  Office of High Energy Physics
 OSTI Identifier:
 1391770
 DOE Contract Number:
 AC0206CH11357
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles, Fields, Gravitation and Cosmology; Journal Volume: 91; Journal Issue: 3
 Country of Publication:
 United States
 Language:
 English
Citation Formats
Montero, J. C., and Sánchez–Vega, B. L. Accidental symmetries and massless quarks in the economical 331 model. United States: N. p., 2015.
Web. doi:10.1103/PhysRevD.91.037302.
Montero, J. C., & Sánchez–Vega, B. L. Accidental symmetries and massless quarks in the economical 331 model. United States. doi:10.1103/PhysRevD.91.037302.
Montero, J. C., and Sánchez–Vega, B. L. 2015.
"Accidental symmetries and massless quarks in the economical 331 model". United States.
doi:10.1103/PhysRevD.91.037302.
@article{osti_1391770,
title = {Accidental symmetries and massless quarks in the economical 331 model},
author = {Montero, J. C. and Sánchez–Vega, B. L.},
abstractNote = {In the framework of a 331 model with a minimal scalar sector, known as the economical 331 model, we study its capabilities of generating realistic quark masses. After a detailed study of the symmetries of the model, before and after the spontaneous symmetry breaking, we find a remaining axial symmetry that prevents some quarks from gaining mass at all orders in perturbation theory. Since this accidental symmetry is anomalous, we also consider briefly the possibility of generating their masses for nonperturbative effects. However, we find that nonperturbative effects are not enough to generate the measured masses for the three massless quarks. Hence, these results imply that the economical 331 model is not a realistic description of the electroweak interaction.},
doi = {10.1103/PhysRevD.91.037302},
journal = {Physical Review. D, Particles, Fields, Gravitation and Cosmology},
number = 3,
volume = 91,
place = {United States},
year = 2015,
month = 2
}

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