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Final-state rescattering mechanism of the Δ(1232)++ production in Λc+→K−π+p decay

Zu-Xin Cai1,2, Cheng Chen2,3, Si-Wei Liu2,3, Xiang Wei2,3, Gang Li1,*, Xiao-Hai Liu4,†, and Ju-Jun Xie2,3,5,‡

  • *Contact author: gli@qfnu.edu.cn
  • †Contact author: xiaohai.liu@tju.edu.cn
  • ‡Contact author: xiejujun@impcas.ac.cn

Phys. Rev. D 114, 034051 – Published 25 August, 2026

DOI: https://doi.org/10.1103/1j49-ks9s

Abstract

We investigate the production of the Δ(1232)++ resonance in the charmed baryon weak decay Λc+→K−π+p, focusing on the π+p final-state rescattering mechanism. The direct W+ exchange diagram is expected to be suppressed, hence we adopt the W+ internal emission process Λc+→pK¯*0(892) followed by the subsequent decay K¯*0→K−π+ as the dominant source of the final state particles. The Δ(1232)++ resonance is then generated via π+p rescattering within a triangle loop mechanism. Our calculations incorporate both the tree-level K¯*0(892) and the dynamically generated K¯0*(700) state arising from the S-wave Kπ final state interaction. We find that our theoretical results can reproduce the bump and peak structures in the K−π+ invariant mass distributions for the K¯0*(700) and K¯*0(892), respectively. Meanwhile, the peak for the Δ(1232)++ in the π+p invariant mass distributions is also well described. The Δ(1232)++ signal naturally emerges from rescattering effects, and adopting the pole parameters of Δ(1232) resonance yields an improved description of the experimental data. In addition, we obtain a branching fraction ratio B[Λc+→Δ(1232)++K−]/B[Λc+→pK¯*0(892)]≈0.5, which is lower than the experimentally measured value. This discrepancy suggests that interference effects are likely significant in this decay process. Future high-precision measurements will further verify the proposed rescattering mechanism.

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References (68)

  1. H.-Y. Cheng, Charmed baryons circa 2015, Front. Phys. (Beijing) 10, 101406 (2015).
  2. E. Oset et al., Weak decays of heavy hadrons into dynamically generated resonances, Int. J. Mod. Phys. E 25, 1630001 (2016).
  3. H.-Y. Cheng, X.-W. Kang, and F. Xu, Singly Cabibbo-suppressed hadronic decays of Λc+, Phys. Rev. D 97, 074028 (2018).
  4. K. Miyahara, T. Hyodo, and E. Oset, Weak decay of Λc+ for the study of Λ(1405) and Λ(1670), Phys. Rev. C 92, 055204 (2015).
  5. J.-J. Xie and L.-S. Geng, The a0(980) and Λ(1670) in the Λc+→π+ηΛ decay, Eur. Phys. J. C 76, 496 (2016).
  6. G.-Y. Wang, N.-C. Wei, H.-M. Yang, E. Wang, L.-S. Geng, and J.-J. Xie, Roles of a0(980), Λ(1670), and Σ(1385) in the Λc+→ηΛπ+ decay, Phys. Rev. D 106, 056001 (2022).
  7. S.-C. Zhang, M.-Y. Duan, W.-T. Lyu, G.-Y. Wang, J.-Y. Zhu, and E. Wang, Explore the properties of Λ(1670) in the Cabibbo-favored process Λc+→pK−π+, Eur. Phys. J. C 84, 1253 (2024).
  8. M.-Y. Duan, M. Bayar, and E. Oset, Precise determination of the ηΛ scattering length and effective range and relationship to the Λ(1670) resonance, Phys. Lett. B 857, 139003 (2024).
  9. J.-J. Xie and L.-S. Geng, Σ1/2−*(1380) in the Λc+→ηπ+Λ decay, Phys. Rev. D 95, 074024 (2017).
  10. J.-J. Xie and L.-S. Geng, Λc+→ηπ+Λ decay and the possible Σ1/2−*(1380), J. Phys. Soc. Jpn. Conf. Proc. 26, 031014 (2019).
  11. W.-T. Lyu, S.-C. Zhang, G.-Y. Wang, J.-J. Wu, E. Wang, L.-S. Geng, and J.-J. Xie, Evidence of the low-lying baryon Σ*(1/2−) in the process Λc+→ηπ+Λ, Phys. Rev. D 110, 054020 (2024).
  12. J.-J. Xie and L.-S. Geng, Role of the N*(1535) in the Λc+→K¯0ηp decay, Phys. Rev. D 96, 054009 (2017).
  13. J.-J. Xie, L.-S. Geng, and F.-K. Guo, Role of N*(1535) in the Λc+→K¯0ηp decay and the possible ϕp state in the Λc+→π0ϕp decay, Eur. Phys. J. Web Conf. 241, 02010 (2020).
  14. Y. Li, S.-W. Liu, E. Wang, D.-M. Li, L.-S. Geng, and J.-J. Xie, Theoretical study of N(1535) and Σ*(1/2−) in the Cabibbo-favored process Λc+→pK¯0η, Phys. Rev. D 110, 074010 (2024).
  15. Y. Li, E. Wang, L.-S. Geng, and J.-J. Xie, Dynamically generated N(1535) state in the Λc+→pK¯0π0 decay, Phys. Rev. D 113, 054039 (2026).
  16. Z. Wang, Y.-Y. Wang, E. Wang, D.-M. Li, and J.-J. Xie, The scalar f0(500) and f0(980) resonances and vector mesons in the single Cabibbo-suppressed decays Λc→pK+K− and pπ+π−, Eur. Phys. J. C 80, 842 (2020).
  17. X.-C. Feng, L.-L. Wei, M.-Y. Duan, E. Wang, and D.-M. Li, The a0(980) in the single Cabibbo-suppressed process Λc→π0ηp, Phys. Lett. B 846, 138185 (2023).
  18. S.-W. Liu, Q.-H. Shen, and J.-J. Xie, Theoretical study on Λc+→ΛK+K¯0 decay and Ξ*(1690) resonance, Phys. Rev. D 108, 114006 (2023).
  19. A. Zupanc et al. (Belle Collaboration), Measurement of the branching fraction B(Λc+→pK−π+), Phys. Rev. Lett. 113, 042002 (2014).
  20. M. Ablikim et al. (BESIII Collaboration), Measurements of absolute hadronic branching fractions of Λc+ baryon, Phys. Rev. Lett. 116, 052001 (2016).
  21. R. Aaij et al. (LHCb Collaboration), Measurements of the branching fractions of Λc+→pπ−π+, Λc+→pK−K+, and Λc+→pπ−K+, J. High Energy Phys. 03 (2018) 043.
  22. M. Berger et al. (Belle Collaboration), Measurement of the decays Λc→Σππ at Belle, Phys. Rev. D 98, 112006 (2018).
  23. J. Y. Lee et al. (Belle Collaboration), Measurement of branching fractions of Λc+→ηΛπ+, ηΣ0π+, Λ(1670)π+, and ηΣ(1385)+, Phys. Rev. D 103, 052005 (2021).
  24. M. Ablikim et al. (BESIII Collaboration), Measurement of the absolute branching fraction of Λc+→pKS0η decays, Phys. Lett. B 817, 136327 (2021).
  25. M. Ablikim et al. (BESIII Collaboration), Partial wave analysis of the charmed baryon hadronic decay Λc+→Λπ+π0, J. High Energy Phys. 12 (2022) 033.
  26. M. Ablikim et al. (BESIII Collaboration), Measurement of the branching fractions of the decays Λc+→ΛKS0K+, Λc+→ΛKS0π+, and Λc+→ΛK*+, Phys. Rev. D 111, 012014 (2025).
  27. M. Ablikim et al. (BESIII Collaboration), Measurement of the branching fractions of the Cabibbo-favored decays Λc+→ΛKS0K+ and Λc+→Ξ0KS0π+ and search for Λc+→Σ0KS0K+, Phys. Rev. D 112, 032006 (2025).
  28. M. Ablikim et al. (BESIII Collaboration), Observation of Λc+→nπ+η and search for Λc+→na0(980)+, arXiv:2603.28232.
  29. M. Ablikim et al. (BESIII Collaboration), Measurements of the absolute branching fractions of the Λc+ hadronic decays, arXiv:2601.01503.
  30. M. Ablikim et al. (BESIII Collaboration), Measurement of the absolute branching fractions of Λc+→Ληπ+ and Σ(1385)+η, Phys. Rev. D 99, 032010 (2019).
  31. M. Ablikim et al. (BESIII Collaboration), Observation of Λc+→Λa0(980)+ and evidence for Σ(1380)+ in Λc+→Λπ+η, Phys. Rev. Lett. 134, 021901 (2025).
  32. L. Li et al. (Belle Collaboration), Measurement of branching fractions of Λc+→pKS0KS0 and Λc+→pKS0η at Belle, Phys. Rev. D 107, 032004 (2023).
  33. E. M. Aitala et al. (E791 Collaboration), Multidimensional resonance analysis of Λc+→pK−π+, Phys. Lett. B 471, 449 (2000).
  34. X.-H. Liu, G. Li, J.-J. Xie, and Q. Zhao, Visible narrow cusp structure in Λc+→pK−π+ enhanced by triangle singularity, Phys. Rev. D 100, 054006 (2019).
  35. J. K. Ahn, S. Yang, and S.-I. Nam, Hyperon production in Λc+→K−pπ+ and Λc+→KS0pπ0, Phys. Rev. D 100, 034027 (2019).
  36. R. Aaij et al. (LHCb Collaboration), Amplitude analysis of the Λc+→pK−π+ decay and Λc+ baryon polarization measurement in semileptonic beauty hadron decays, Phys. Rev. D 108, 012023 (2023).
  37. D.-H. Wei, Y.-X. Yang, and R.-G. Ping, Using Λc+→pK−π+ as a spin polarimeter, Chin. Phys. C 46, 074002 (2022).
  38. S. Navas et al. (Particle Data Group), Review of particle physics, Phys. Rev. D 110, 030001 (2024).
  39. D. Marangotto, Extracting maximum information from polarised baryon decays via amplitude analysis: The Λc+→pK−π+ case, Adv. High Energy Phys. 2020, 7463073 (2020).
  40. H. L. Anderson, E. Fermi, E. A. Long, and D. E. Nagle, Total cross-sections of positive pions in hydrogen, Phys. Rev. 85, 936 (1952).
  41. F. Huang, M. Doring, H. Haberzettl, J. Haidenbauer, C. Hanhart, S. Krewald, U. G. Meissner, and K. Nakayama, Pion photoproduction in a dynamical coupled-channels model, Phys. Rev. C 85, 054003 (2012).
  42. M.-Y. Dai, S.-W. Liu, C. Chen, D.-M. Li, E. Wang, and J.-J. Xie, Roles of Δ(1232), N*(1520), and N*(1650) resonances in γp→π0π0p reaction within an effective Lagrangian approach, Chin. Phys. C 49, 063102 (2025).
  43. N. Muramatsu et al. (LEPS2/BGOegg Collaboration), First measurement of differential cross sections and photon beam asymmetries for photoproduction of the f0(980) meson decaying into π0π0 at Eγ<2.4  GeV, Phys. Rev. C 107, L042201 (2023).
  44. F. Aceti, L. R. Dai, L. S. Geng, E. Oset, and Y. Zhang, Meson-baryon components in the states of the baryon decuplet, Eur. Phys. J. A 50, 57 (2014).
  45. T. Sekihara, T. Arai, J. Yamagata-Sekihara, and S. Yasui, Compositeness of the Δ(1232) resonance in πN scattering, J. Phys. Soc. Jpn. Conf. Proc. 10, 022005 (2016).
  46. T. Sekihara, T. Arai, J. Yamagata-Sekihara, and S. Yasui, Compositeness of baryonic resonances: Application to the Δ(1232), N(1535), and N(1650) resonances, Phys. Rev. C 93, 035204 (2016).
  47. H.-Y. Cheng and C.-W. Chiang, Hadronic D decays involving even-parity light mesons, Phys. Rev. D 81, 074031 (2010).
  48. K. Miyahara, T. Hyodo, M. Oka, J. Nieves, and E. Oset, Theoretical study of the Ξ(1620) and Ξ(1690) resonances in Ξc→π+MB decays, Phys. Rev. C 95, 035212 (2017).
  49. J.-J. Xie, L.-R. Dai, and E. Oset, The low lying scalar resonances in the D0 decays into Ks0 and f0(500), f0(980), a0(980), Phys. Lett. B 742, 363 (2015).
  50. J. R. Peláez and A. Rodas, Dispersive πK→πK and ππ→KK¯ amplitudes from scattering data, threshold parameters, and the lightest strange resonance κ or K0*(700), Phys. Rep. 969, 1 (2022).
  51. M. Albaladejo, A. Canoa, J. Nieves, J. R. Peláez, E. Ruiz-Arriola, and J. R. de Elvira, The role of chiral symmetry and the non-ordinary κ/K0*(700) nature in π±KS femtoscopic correlations, Phys. Lett. B 866, 139552 (2025).
  52. K. P. Khemchandani, A. Martínez Torres, A. Hosaka, H. Nagahiro, F. S. Navarra, and M. Nielsen, Why Ξ(1690) and Ξ(2120) are so narrow?, Phys. Rev. D 97, 034005 (2018).
  53. G. Toledo, N. Ikeno, and E. Oset, Theoretical study of the D0→K−π+η reaction, Eur. Phys. J. C 81, 268 (2021).
  54. J. A. Oller and E. Oset, Chiral symmetry amplitudes in the S-wave isoscalar and isovector channels and the σ, f0(980), a0(980) scalar mesons, Nucl. Phys. A620, 438 (1997); A652, 407(E) (1999).
  55. J. A. Oller, E. Oset, and J. R. Pelaez, Meson meson interaction in a nonperturbative chiral approach, Phys. Rev. D 59, 074001 (1999); 60, 099906(E) (1999); 75, 099903(E) (2007).
  56. J. A. Oller, E. Oset, and J. R. Pelaez, Nonperturbative approach to effective chiral Lagrangians and meson interactions, Phys. Rev. Lett. 80, 3452 (1998).
  57. D. Gamermann, E. Oset, D. Strottman, and M. J. Vicente Vacas, Dynamically generated open and hidden charm meson systems, Phys. Rev. D 76, 074016 (2007).
  58. D. Lee and S.-i. Nam, Strangeness plus-one (S=+1) resonance-state P0+* via K+n→K*0p, Phys. Rev. C 109, 045207 (2024).
  59. Y.-K. Chen, Y. Pan, and B.-C. Liu, Δ(1232) production in the γp→ϕπp reaction, Phys. Rev. D 112, 074013 (2025).
  60. O. Gortchakov, M. P. Locher, V. E. Markushin, and S. von Rotz, Two meson doorway calculation for p¯p→ϕπ including off-shell effects and the OZI rule, Z. Phys. A 353, 447 (1996).
  61. N. A. Tornqvist, From the deuteron to deusons, an analysis of deuteronlike meson meson bound states, Z. Phys. C 61, 525 (1994).
  62. H.-Y. Cheng, C.-K. Chua, and A. Soni, Final state interactions in hadronic B decays, Phys. Rev. D 71, 014030 (2005).
  63. X.-Q. Li, D. V. Bugg, and B.-S. Zou, Possible explanation of the “ρπ puzzle” in J/ψ, ψ′ decays, Phys. Rev. D 55, 1421 (1997).
  64. M. P. Locher, Y. Lu, and B. S. Zou, Rates for the reactions p¯p→πϕ and γϕ, Z. Phys. A 347, 281 (1994).
  65. V. Shklyar, H. Lenske, and U. Mosel, A coupled-channel analysis of KΛ production in the nucleon resonance region, Phys. Rev. C 72, 015210 (2005).
  66. T. Feuster and U. Mosel, A unitary model for meson nucleon scattering, Phys. Rev. C 58, 457 (1998).
  67. R. Brockmann and R. Machleidt, Relativistic nuclear structure. I. Nuclear matter, Phys. Rev. C 42, 1965 (1990).
  68. R. Machleidt, K. Holinde, and C. Elster, The Bonn meson-exchange model for the nucleon-nucleon interaction, Phys. Rep. 149, 1 (1987).

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