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Pion radiative decays of excited hidden-charm pentaquark molecules: From $Σ_{c}^{()} {\bar{D}}^{()} (2 S)$ molecules to the reported $P_{c}$ states

Yu-Jie Tang ¹, Wen-Yan Peng^1,2,*, Rui Chen ^1,2,†, and Fu-Lai Wang³

¹Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Department of Physics and Synergetic Innovation Center for Quantum Effects and Applications, Hunan Normal University, Changsha 410081, China
²Hunan Research Center of the Basic Discipline for Quantum Effects and Quantum Technologies, Hunan Normal University, Changsha 410081, China
³School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China

^*Contact author: 11636017@zju.edu.cn
^†Contact author: chenrui@hunnu.edu.cn

Phys. Rev. D 114, 074008 – Published 2 October, 2026

DOI: https://doi.org/10.1103/fgdl-7lb7

Abstract

The discovery of the hidden-charm pentaquarks $P_{c} (4312)$ , $P_{c} (4440)$ , and $P_{c} (4457)$ by the LHCb Collaboration are very likely to identify as the $Σ_{c}^{(*)} {\bar{D}}^{(*)}$ molecules. A natural and crucial extension is the existence of excited molecular partners built from a ground-state charmed baryon and a radially excited anticharmed meson, namely $Σ_{c}^{(*)} {\bar{D}}^{(*)} (2 S)$ molecules. In a framework of the chiral quark model, we systematically study pion-emission decays of such excited molecules into the known ground-state $P_{c}$ molecules. Our results show that the decay widths are sensitive to the spin structures and the coupled-channel interferences, i.e., the $Σ_{c} \bar{D} (2 S) / Σ_{c} {\bar{D}}^{*} (2 S) / Σ_{c}^{*} {\bar{D}}^{*} (2 S) [1 / 2 (1 / 2^{-})]$ state decays to $P_{c} (4440)$ with a width of several MeV, while the width to $P_{c} (4457)$ is suppressed below 0.3 MeV due to destructive interference. The pion-emission decay can be the key to unveiling the excited molecular spectrum of hidden-charm pentaquarks and provides decisive experimental signatures. We expect that future experiments such as the LHCb and PANDA can verify our predictions.

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References (77)

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Phys. Rev. D 114, 074008– Published 2 October, 2026

Vol. 114, Iss. 7 — 1 October 2026

Received 17 June 2026
Accepted 1 September 2026

DOI: https://doi.org/10.1103/fgdl-7lb7

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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Pion radiative decays of excited hidden-charm pentaquark molecules: From $Σ_{c}^{()} {\bar{D}}^{()} (2 S)$ molecules to the reported $P_{c}$ states

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Pion radiative decays of excited hidden-charm pentaquark molecules: From Σc(*)D¯(*)(2S) molecules to the reported Pc states

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References (77)

Pion radiative decays of excited hidden-charm pentaquark molecules: From $Σ_{c}^{()} {\bar{D}}^{()} (2 S)$ molecules to the reported $P_{c}$ states