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Implications of flavor symmetries for baryon number violation

Arnau Bas i Beneito1,*, Ajdin Palavrić1,2,†, and Andrea Sainaghi3,4,5,‡

  • *Contact author: arnau.bas@ific.uv.es
  • †Contact author: ajdin.palavric@ific.uv.es
  • ‡Contact author: andrea.sainaghi@phd.unipd.it
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Phys. Rev. D 113, 055021 – Published 12 March, 2026

DOI: https://doi.org/10.1103/dlq2-9yl8

Abstract

In the Standard Model, baryon number is an accidental symmetry, whose violation would constitute unambiguous evidence of new physics, with proton decay providing its most prominent experimental signature. At the same time, the peculiar structure of flavor can serve as a guiding principle for exploring possible new-physics effects. In this work, we present a systematic classification of dimension-six baryon-number-violating (BNV) standard model effective field theory (SMEFT) operators across several flavor-symmetry assumptions and analyze the resulting phenomenology. Interestingly, in certain flavor scenarios the nontrivial interplay with tiny neutrino masses leads to proton-decay constraints compatible with BNV scales in the multi-TeV range. Finally, we complement the EFT analysis by identifying one-particle UV completions of the BNV operators, revealing scenarios in which the leading-order EFT description may not fully account for their underlying dynamics.

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Phys. Rev. D 113, 055021– Published 12 March, 2026
  • Received 24 December 2025
  • Accepted 11 February 2026
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