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Probing the spin-parity structure of hidden-charm pentaquarks from spectroscopy and magnetic moments

Department of Physics and Materials Science, Thapar Institute of Engineering and Technology, Patiala, India

^*Contact author: pallavi.gupta@thapar.edu

Phys. Rev. D 113, 075019 – Published 16 April, 2026

DOI: https://doi.org/10.1103/b7ry-sr11

Abstract

We investigate the spin-parity ( $J^{P}$ ) assignments of experimentally observed hidden-charm pentaquark states within a baryon-meson molecular framework. The pentaquark mass spectrum is obtained using the Gürsey-Radicati mass formula, with parameters fixed through a global fit to 41 experimentally established hadron masses. The resulting spectrum is then used to assign $J^{P}$ quantum numbers to the observed pentaquark candidates. Within this framework, the nonstrange states $P_{c} (4312)$ , $P_{c} (4440)$ , and $P_{c} (4457)$ are identified with the $J^{P} = 1 / 2^{-}$ , $3 / 2^{-}$ , and $5 / 2^{-}$ configurations, respectively. The recently reported Belle state $P_{c s} (4459)$ , which carries strangeness, is interpreted as the strange member of the SU(3) flavor octet with $J^{P} = 3 / 2^{-}$ . Magnetic moments are subsequently evaluated using explicitly constructed wave functions. Their systematic behavior across SU(3) flavor multiplets and different spin-parity assignments satisfies the expected sum-rule relations and indicates that magnetic moments can serve as a useful observable for refining the quantum-number identification of hidden-charm pentaquark states in future studies.

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Phys. Rev. D 113, 075019– Published 16 April, 2026

Vol. 113, Iss. 7 — 1 April 2026

Received 11 January 2026
Accepted 6 March 2026

DOI: https://doi.org/10.1103/b7ry-sr11

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

Published by the American Physical Society

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Probing the spin-parity structure of hidden-charm pentaquarks from spectroscopy and magnetic moments

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