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$C P$ violation in hadronic weak decays of charmed baryons in the topological diagrammatic approach

Hai-Yang Cheng

Fanrong Xu ^* and Huiling Zhong

Institute of Physics, Academia Sinica, Taipei, Taiwan 11529, Republic of China

Department of Physics, College of Physics and Optoelectronic Engineering, Jinan University, Guangzhou 510632, People’s Republic of China

^*Contact author: fanrongxu@jnu.edu.cn

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Phys. Rev. D 112, 054022 – Published 12 September, 2025

DOI: https://doi.org/10.1103/n8fk-v7r8

Abstract

$C P$ violation in the charmed baryon sector is generally expected to be very small, of order $10^{- 4}$ or even smaller. Nevertheless, large long-distance penguin topologies can be induced through final-state rescattering. At the hadron level, they are manifested as the triangle and bubble diagrams. However, these diagrams consist of not only the penguin but also other tree topologies. Therefore, we focus on the flavor structure of the these diagrams and project out their contributions to penguin and tree topologies. The analysis is performed within the framework of the topological diagram approach and the irreducible SU(3) approach in which the SU(3) flavor symmetry of QCD is realized to describe the nonleptonic decays of charmed baryons. $C P$ violation at the per mille level is found in the following decay modes: $Λ_{c}^{+} \to p π^{0}, Λ_{c}^{+} \to p η^{'}, Ξ_{c}^{0} \to Σ^{0} η$ , and $Ξ_{c}^{+} \to Σ^{+} η$ . $C P$ asymmetries in the last three modes receive sizable contributions from the SU(3)-flavor-singlet hairpin diagram.

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Phys. Rev. D 112, 054022– Published 12 September, 2025

Vol. 112, Iss. 5 — 1 September 2025

Received 15 May 2025
Accepted 15 August 2025

DOI: https://doi.org/10.1103/n8fk-v7r8

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.

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$C P$ violation in hadronic weak decays of charmed baryons in the topological diagrammatic approach

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CP violation in hadronic weak decays of charmed baryons in the topological diagrammatic approach

Abstract

Physics Subject Headings (PhySH)

Article Text

References (56)

$C P$ violation in hadronic weak decays of charmed baryons in the topological diagrammatic approach