Probing the isospin structure and low-lying resonances in Λ c + → n K ¯ 0 π + decays
Year: 2026
Type: article
Abstract: The Cabibbo-favored decay Λ c + → n K ¯ 0 π + offers a unique window to explore unresolved puzzles in the low-energy baryon spectroscopy and the isospin dynamics of the K ¯ N system. Recent experimental results present a, for now, contradiction: LHCb and Belle analyses of Λ c + → p K − π + suggest the p K − ( I = 0 ) component dominates, while the Beijing Spectrometer III (BESIII) hints at significant contributions from both isospin 0 and 1 in the n K ¯ 0 system of Λ c + → n K S 0 π + . Furthermore, the measured branching fraction of Λ c + → n K S 0 π + exceeds SU(3) symmetry predictions by a factor of 3–4, signaling strong contributions from low-lying resonances. In this work, we provide a theoretical analysis of Λ c + → n K ¯ 0 π + within the coupled-channel chiral unitary approach, where the N ( 1535 ) and Λ ( 1670 ) can be dynamically generated. Our calculations show a narrow peak from N ( 1535 ) in the π + n invariant mass spectrum and a distinct dip from Λ ( 1670 ) in the K ¯ 0 n spectrum. The dip structure is qualitatively consistent with the Λ ( 1670 ) manifestation in K ¯ N → K ¯ N scattering, supporting its molecular interpretation. This study not only connects the experimental observations but also highlights Λ c +
DOI: 10.1103/s3bp-h492
Institutions: Zhengzhou University, Henan University, Henan Normal University
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W7154452006