Revisiting the Λc+ → nπ+η decay in light of the BESIII measurement
Abstract
Motivated by the recent BESIII measurement, we revisit the Λc+→ nπ+η decay within the chiral unitary approach, including internal and external W-emission mechanisms and final-state interactions. The a0(980)+ and N(1535)0,+ resonances are dynamically generated by meson--meson and meson--baryon interactions, respectively. With the relative weight of internal to external emission fixed at 1/3, 2/3, and $1$, all three scenarios reasonably describe the measured π+η invariant mass distribution, but yield different fractions for the a0(980) contribution, and the fraction obtained for γ=2/3 and $1$ are numerically below the experimental upper limit. The a0(980) contribution exhibits a threshold cusp, modified by coherent interference in the total spectrum. Its modest prominence, together with the limited statistical precision and coarse binning, offers a plausible explanation for the absence of a clear experimental signal. We also predict the ηn and π+n invariant mass distributions. Future high-statistics measurements at BESIII, Belle~II, and STCF would enable a joint analysis to constrain the relative production weight and resonance contributions, providing further insight into the nature of the a0(980) and N(1535).
Related
- Measurement of electromagnetic transition form factors in two-photon collisions at BESIII
- Light meson decays at BESIII
- Precision measurement of the J/ψ→μ+μ-μ+μ- branching fraction and search for a new gauge boson Z′ at BESIII
- Revisiting B̅0 → Λc+ p̅ decay with higher twist corrections
- Revisiting the gamma-ray signal from light ALPs emitted during the evaporation of memory-burdened PBHs
BibTeX
@misc{li2026revisiting,
title = {{Revisiting the $Λ_c^+ \to nπ^+η$ decay in light of the BESIII measurement}},
author = {Meng-Yuan Li and Jing Tang and Wen-Tao Lyu and Shi-Chen Xue and En Wang},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2608.05629},
eprint = {2608.05629},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2608.05629},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Revisiting the Λ_c^+ → nπ^+η decay in light of the BESIII measurement
AU - Meng-Yuan Li
AU - Jing Tang
AU - Wen-Tao Lyu
AU - Shi-Chen Xue
AU - En Wang
PY - 2026
DA - 2026/10/18
PB - arXiv
DO - 10.48550/arxiv.2608.05629
UR - https://arxiv.org/abs/2608.05629
AB - Motivated by the recent BESIII measurement, we revisit the Λ_c^+→ nπ^+η decay within the chiral unitary approach, including internal and external W-emission mechanisms and final-state interactions. The a_0(980)^+ and N(1535)^0,+ resonances are dynamically generated by meson--meson and meson--baryon interactions, respectively. With the relative weight of internal to external emission fixed at 1/3, 2/3, and $1$, all three scenarios reasonably describe the measured π^+η invariant mass distribution, but yield different fractions for the a_0(980) contribution, and the fraction obtained for γ=2/3 and $1$ are numerically below the experimental upper limit. The a_0(980) contribution exhibits a threshold cusp, modified by coherent interference in the total spectrum. Its modest prominence, together with the limited statistical precision and coarse binning, offers a plausible explanation for the absence of a clear experimental signal. We also predict the ηn and π^+n invariant mass distributions. Future high-statistics measurements at BESIII, Belle~II, and STCF would enable a joint analysis to constrain the relative production weight and resonance contributions, providing further insight into the nature of the a_0(980) and N(1535).
ER -