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  • Open Access

New Chiral Structures for Baryon Number Violating Nucleon Decays

Yi Liao*, Xiao-Dong Ma†, and Hao-Lin Wang‡

  • *Contact author: liaoy@m.scnu.edu.cn
  • †Contact author: maxid@scnu.edu.cn
  • ‡Contact author: whaolin@m.scnu.edu.cn
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Phys. Rev. Lett. 135, 161801 – Published 14 October, 2025

DOI: https://doi.org/10.1103/d8m7-5xxx

Abstract

We examine the most general nucleon decay interactions that involve three light quarks without being acted upon by a derivative. We identify four generic operator structures that correspond to the irreducible representations in the chiral group SU(3)L⊗SU(3)R of QCD, {8L⊗1R,3¯L⊗3R,6L⊗3R,10L⊗1R}, plus their chirality partners under the interchange of chiralities L↔R. While half of them have been extensively discussed in the literature, the other half, 6L(R)⊗3R(L) and 10¯L(R)⊗1R(L), are identified for the first time. We perform chiral matching for these interactions at the leading chiral order and find that each has a unique chiral realization in terms of the octet baryons and pseudoscalars. Notably, the chiral interaction in the 6L(R)⊗3R(L) representation appears at the same chiral order as those of the known ones, while the one in the 10L(R)⊗1R(L) representation appears at a higher chiral order. These new structures are prevalent in effective field theories and ultraviolet models, and they offer novel experimental avenues to search for baryon number violating nucleon decays.

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Phys. Rev. Lett. 135, 161801– Published 14 October, 2025
  • Received 28 April 2025
  • Revised 7 August 2025
  • Accepted 22 September 2025
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