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  • Open Access

Investigating topped hadrons to probe the boundaries of the potential model

Si-Qiang Luo1,3,5,*, Qi Huang2,3,†, and Xiang Liu1,3,4,5,‡

  • 1School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China
  • 2School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China
  • 3Lanzhou Center for Theoretical Physics, Key Laboratory of Theoretical Physics of Gansu Province, Key Laboratory of Quantum Theory and Applications of MoE, Gansu Provincial Research Center for Basic Disciplines of Quantum Physics, Lanzhou University, Lanzhou 730000, China
  • 4MoE Frontiers Science Center for Rare Isotopes, Lanzhou University, Lanzhou 730000, China
  • 5Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS, Lanzhou 730000, China

  • *Contact author: luosq15@lzu.edu.cn
  • †Contact author: 06289@njnu.edu.cn
  • ‡Contact author: xiangliu@lzu.edu.cn
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Phys. Rev. D 113, 094033 – Published 26 May, 2026

DOI: https://doi.org/10.1103/rvpg-vhkx

Abstract

Inspired by the recent discovery of a pseudoscalar enhancement structure near the tt¯ threshold reported by the CMS and ATLAS Collaborations, this work investigates the mass spectra of single topped hadrons—including both topped mesons and topped baryons—based on a relativistic potential model. Using the same parameters obtained from the fit to mesons and baryons, we provide predictions for the mass spectra of ground and low-lying orbitally excited single topped mesons and baryons. In addition, we point out that the precise measurement of the tt¯ mass could test the limitation of the potential model. Given the extremely large mass of the topped quark, we discuss spectroscopic properties of topped hadrons in the approximation of an ideal heavy-quark limit.

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Phys. Rev. D 113, 094033– Published 26 May, 2026
  • Received 31 August 2025
  • Accepted 17 April 2026
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