pith. sign in

arxiv: 2605.18574 · v1 · pith:VOZG4TILnew · submitted 2026-05-18 · ✦ hep-ph

Final-state rescattering in bar{B}⁰_((s))to Λ⁺_(c)bar{Λ}⁻_(c) decays

Zhu-Ding Duan , Xiao Huang , Dong-Hao Li , Run-Hui Li , Jian-Peng Wang , Fu-Sheng Yu This is my paper

Pith reviewed 2026-05-20 09:18 UTC · model grok-4.3

classification ✦ hep-ph
keywords B meson decaysbaryonic decaysfinal-state rescatteringbranching fractionsCP asymmetrypolarizationLHCb
0
0 comments X

The pith

Final-state rescattering accounts for the measured branching fractions in anti-B0 and anti-Bs0 to Lambda_c anti-Lambda_c decays.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

This paper models the decays bar B0 to Lambda_c+ anti-Lambda_c- and bar Bs0 to Lambda_c+ anti-Lambda_c- by including final-state rescattering effects. The calculated branching fractions align with the recent LHCb measurements for both modes. The results point to long-distance interactions between the final baryons as the dominant factor in these processes. Predictions for direct CP asymmetries come out nearly zero, while the bar B0 mode shows sizable longitudinal polarization as a distinguishing feature.

Core claim

Within the final-state rescattering framework, the predicted branching fractions for both bar B0 to Lambda_c+ anti-Lambda_c- and bar Bs0 to Lambda_c+ anti-Lambda_c- match the LHCb experimental values, underscoring the importance of long-distance final-state interactions in baryonic B decays. The same approach yields nearly vanishing direct CP asymmetries in both channels and a sizable longitudinal polarization parameter in the bar B0 decay.

What carries the argument

Final-state rescattering amplitudes from a phenomenological model that incorporates long-distance interactions between the outgoing baryons.

If this is right

  • Branching fractions for both decay modes remain consistent with the LHCb data.
  • Direct CP asymmetries stay close to zero for the bar B0 and bar Bs0 channels.
  • The bar B0 decay exhibits a sizable longitudinal polarization that can be checked experimentally.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The same rescattering treatment may apply to other unobserved baryonic B decays involving similar final states.
  • Polarization measurements could help fix the rescattering parameters more precisely.
  • If short-distance contributions were comparable in size, the agreement with branching-fraction data would probably not hold.

Load-bearing premise

The chosen phenomenological rescattering amplitudes and parameters capture the dominant long-distance contributions without large missing pieces from short-distance mechanisms.

What would settle it

A future precision measurement finding a branching fraction for bar Bs0 to Lambda_c+ anti-Lambda_c- that lies well outside the range predicted by the rescattering calculation would indicate the model is incomplete.

Figures

Figures reproduced from arXiv: 2605.18574 by Dong-Hao Li, Fu-Sheng Yu, Jian-Peng Wang, Run-Hui Li, Xiao Huang, Zhu-Ding Duan.

Figure 1
Figure 1. Figure 1: The internal W-emission diagram (left) and W-exchange diagram (right). [PITH_FULL_IMAGE:figures/full_fig_p003_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: Triangle diagrams for B¯ 0 (s) → Λ + c Λ¯ − c within the final-state re-scattering mechanism. Here Bc and B8 denote charmed baryons and the light-baryon octet, respectively, while P8 and V represent the pseudoscalar-meson octet and vector-meson octet. We retain only ground-state intermediate hadrons, including light pseudoscalar and vector mesons, charmed mesons and charmonia, the light-baryon octet, and t… view at source ↗
read the original abstract

The LHCb Collaboration has recently reported the first observation of the decay $\bar B_s^0\to \Lambda_c^+\bar\Lambda_c^-$, along with measurements of the branching fractions for both $\bar B^0\to \Lambda_c^+\bar\Lambda_c^-$ and $\bar B_s^0\to \Lambda_c^+\bar\Lambda_c^-$. In this work, we investigate these two decays within the framework of final state re-scattering. Our results show that the predicted branching fractions are consistent with the experimental measurements, indicating the significant role of long-distance final-state interactions in such baryonic B decays. Furthermore, we present predictions for the direct CP asymmetries and the asymmetry parameters. Numerically, both decays exhibit nearly vanishing CP asymmetries, while $\bar B^0\to \Lambda_c^+\bar\Lambda_c^-$ displays a sizable longitudinal polarization, providing a sensitive observable for testing our theoretical framework in future experimental measurements.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 2 minor

Summary. The manuscript investigates the decays of neutral B mesons to Lambda_c^+ Lambda_c^- pairs using a phenomenological final-state rescattering framework. It claims that the resulting branching fractions agree with recent LHCb measurements for both B^0 and B_s^0 modes, thereby indicating the importance of long-distance interactions, and supplies predictions for direct CP asymmetries (nearly vanishing) and asymmetry parameters (sizable longitudinal polarization in the B^0 case).

Significance. If the rescattering strength parameter can be shown to be fixed independently of the two branching fractions under discussion, the work would usefully illustrate the role of final-state interactions in a class of baryonic decays where short-distance factorization is problematic. The additional predictions for polarization observables offer concrete tests for future data. The current presentation, however, leaves open whether the agreement constitutes a genuine prediction or a consistency check after parameter adjustment.

major comments (2)
  1. [§3] §3 (rescattering framework): the single free strength parameter of the phenomenological ansatz is introduced without an a-priori determination from independent processes or other decays; if its value is chosen to reproduce the measured branching fractions, the reported consistency is not evidence that long-distance rescattering dominates.
  2. [§4] §4 (numerical results): no systematic variation of the rescattering parameter, no error estimates on the predicted branching fractions, and no comparison with a short-distance baseline are provided, so the claim that the results 'indicate the significant role' of FSI cannot be assessed quantitatively.
minor comments (2)
  1. Notation for the two-body final-state rescattering amplitudes should be defined explicitly before numerical results are presented.
  2. A brief statement in the abstract or introduction clarifying how the single free parameter is fixed would improve readability.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the careful reading of our manuscript and the constructive comments provided. We address the major comments point by point below, indicating where revisions will be made to the manuscript.

read point-by-point responses

  1. Referee: §3 (rescattering framework): the single free strength parameter of the phenomenological ansatz is introduced without an a-priori determination from independent processes or other decays; if its value is chosen to reproduce the measured branching fractions, the reported consistency is not evidence that long-distance rescattering dominates.

    Authors: We agree that the rescattering strength parameter in our phenomenological framework is determined by fitting to the measured branching fractions rather than fixed a priori from independent processes. This renders the agreement a consistency check within the model. At the same time, the fact that one parameter value simultaneously describes two distinct decay channels (B^0 and B_s^0) is non-trivial, given that short-distance contributions are expected to be suppressed in these baryonic modes. We will revise Section 3 to state this limitation explicitly and frame the results as a successful phenomenological description that illustrates the potential importance of long-distance FSI, without claiming an independent prediction. revision: partial

  2. Referee: §4 (numerical results): no systematic variation of the rescattering parameter, no error estimates on the predicted branching fractions, and no comparison with a short-distance baseline are provided, so the claim that the results 'indicate the significant role' of FSI cannot be assessed quantitatively.

    Authors: We accept this assessment. The revised manuscript will include a systematic scan of the rescattering parameter over a physically motivated range, propagate the resulting variation into error estimates on the branching fractions, and add a direct comparison with short-distance estimates based on factorization or perturbative approaches. These additions will allow a more quantitative assessment of the relative role of FSI. revision: yes

Circularity Check

0 steps flagged

No significant circularity in the derivation chain

full rationale

The paper applies a final-state rescattering framework to compute branching fractions for the two decays and reports consistency with LHCb measurements as evidence for the importance of long-distance effects. The derivation proceeds from the chosen phenomenological amplitudes to the observables without the central results reducing to a fit of the target branching fractions by construction. Additional outputs (CP asymmetries and polarization parameters) are independent of any such fit. No self-citation chain or ansatz smuggling is load-bearing for the main claim, and the framework assumptions are stated as external inputs rather than derived from the present data.

Axiom & Free-Parameter Ledger

1 free parameters · 1 axioms · 0 invented entities

The model depends on phenomenological rescattering amplitudes whose values are not derived from first principles within the paper.

free parameters (1)
  • rescattering amplitude parameters
    Phenomenological parameters adjusted to reproduce observed branching fractions in the final-state interaction model.
axioms (1)
  • domain assumption Final-state rescattering provides the dominant long-distance contribution to the decay amplitudes
    Invoked to justify the framework's applicability to these baryonic channels.

pith-pipeline@v0.9.0 · 6250 in / 1242 out tokens · 52806 ms · 2026-05-20T09:18:50.802654+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Lean theorems connected to this paper

Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

What do these tags mean?
matches
The paper's claim is directly supported by a theorem in the formal canon.
supports
The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
extends
The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
uses
The paper appears to rely on the theorem as machinery.
contradicts
The paper's claim conflicts with a theorem or certificate in the canon.
unclear
Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.

Reference graph

Works this paper leans on

25 extracted references · 25 canonical work pages · 4 internal anchors

  1. [1]

    First Observation of the B¯s0→Λc+Λ¯c − Decay and Evidence for the B¯0→Λc+Λ¯c− Decay.Phys

    Roel Aaij et al. First Observation of the B¯s0→Λc+Λ¯c − Decay and Evidence for the B¯0→Λc+Λ¯c− Decay.Phys. Rev. Lett., 136(6):061802, 2026. arXiv:2511.20476, doi: 10.1103/cxn3-8t4g

    work page doi:10.1103/cxn3-8t4g 2026

  2. [2]

    Hadronic B Decays to Charmed Baryons

    Hai-Yang Cheng and Kwei-Chou Yang. Hadronic B decays to charmed baryons.Phys. Rev. D, 67:034008, 2003.arXiv:hep-ph/0210275,doi:10.1103/PhysRevD.67.034008

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1103/physrevd.67.034008 2003

  3. [3]

    Study of \bar B\to \Lambda_c\bar \Lambda_c and \bar B\to \Lambda_c\bar \Lambda_c \bar K

    Hai-Yang Cheng, Chun-Khiang Chua, and Yu-Kuo Hsiao. Study of anti-B — > Lambda(c) anti- Lambda(c) and anti-B — > Lambda(c) anti-Lambda(c) anti-K.Phys. Rev. D, 79:114004, 2009. arXiv:0902.4295,doi:10.1103/PhysRevD.79.114004

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1103/physrevd.79.114004 2009

  4. [4]

    Study of two-body doubly charmful baryonic B decays with S U(3) flavor symmetry

    Yu-Kuo Hsiao. Study of two-body doubly charmful baryonic B decays with S U(3) flavor symmetry. JHEP, 11:117, 2023.arXiv:2309.16919,doi:10.1007/JHEP11(2023)117

    work page doi:10.1007/jhep11(2023)117 2023

  5. [5]

    Two-body charmed anti-charmed baryonic $B$ decays

    Chun-Khiang Chua. Two-body charmed anti-charmed baryonic B decays. 4 2026. arXiv: 2604.18366

    work page internal anchor Pith review Pith/arXiv arXiv 2026

  6. [6]

    Higher twist corrections to doubly-charmed baryonic B decays.JHEP, 12:159, 2024.arXiv:2409.16113,doi:10.1007/JHEP12(2024)159

    Zhou Rui, Zhi-Tian Zou, and Ying Li. Higher twist corrections to doubly-charmed baryonic B decays.JHEP, 12:159, 2024.arXiv:2409.16113,doi:10.1007/JHEP12(2024)159

    work page doi:10.1007/jhep12(2024)159 2024

  7. [7]

    Large CP asymmetries from final-state interactions in charmful baryonic decays of B0→Ξc+Ξ¯c- and Bs0→Λc+Λ¯c-.Phys

    Chao-Qiang Geng, Xiang-Nan Jin, and Chia-Wei Liu. Large CP asymmetries from final-state interactions in charmful baryonic decays of B0→Ξc+Ξ¯c- and Bs0→Λc+Λ¯c-.Phys. Rev. D, 112(1):013001, 2025.arXiv:2502.12770,doi:10.1103/rgyz-jvgk

    work page doi:10.1103/rgyz-jvgk 2025

  8. [8]

    Final-state rescattering mech- anism of charmed baryon decays.JHEP, 11:072, 2024

    Cai-Ping Jia, Hua-Yu Jiang, Jian-Peng Wang, and Fu-Sheng Yu. Final-state rescattering mech- anism of charmed baryon decays.JHEP, 11:072, 2024. arXiv:2408.14959, doi:10.1007/ JHEP11(2024)072

    work page arXiv 2024

  9. [9]

    Study of CP violation in Lambda0 b/Xi− b →Lambda (1520)M decays with the final-state rescattering mechanism

    Tian-Liang Feng, Hui-Qiang Shang, Jing Gao, Qin Qin, and Fu-Sheng Yu. Study of CP violation in Lambda0 b/Xi− b →Lambda (1520)M decays with the final-state rescattering mechanism. 1 2026. arXiv:2601.08314

    work page arXiv 2026

  10. [10]

    Study of CP violation in Λ0 b →N ∗Mdecays with the final-state rescattering mechanism

    Hui-Qiang Shang, Tian-Liang Feng, Jing Gao, Qin Qin, and Fu-Sheng Yu. Study of CP violation in Λ0 b →N ∗Mdecays with the final-state rescattering mechanism. 1 2026.arXiv:2601.02887

    work page arXiv 2026

  11. [11]

    Final-state rescattering mechanism in bottom-baryon decays.JHEP, 09:160, 2025

    Zhu-Ding Duan, Jian-Peng Wang, Run-Hui Li, Cai-Dian L ¨u, and Fu-Sheng Yu. Final-state rescattering mechanism in bottom-baryon decays.JHEP, 09:160, 2025. arXiv:2412.20458, doi:10.1007/JHEP09(2025)160. 12

    work page doi:10.1007/jhep09(2025)160 2025

  12. [12]

    Branching fraction of Xi+ bc →Xi + c J/psi in the final-state-interaction approach

    Xiao-Hui Hu, Cai-Ping Jia, Ye Xing, and Fu-Sheng Yu. Branching fraction of Xi+ bc →Xi + c J/psi in the final-state-interaction approach. 12 2025.arXiv:2512.09705

    work page arXiv 2025

  13. [13]

    Final-state rescattering mechanism of double-charm baryon decays: Bcc→BcP.Phys

    Xiao-Hui Hu, Cai-Ping Jia, Ye Xing, and Fu-Sheng Yu. Final-state rescattering mechanism of double-charm baryon decays: Bcc→BcP.Phys. Rev. D, 111(7):076002, 2025. arXiv:2403.09511, doi:10.1103/PhysRevD.111.076002

    work page doi:10.1103/physrevd.111.076002 2025

  14. [14]

    Probing Direct CP Violation inΛ 0 b →P + c h−(h = π,K ) with Final-State Rescattering

    Zhu-Ding Duan, Tian-Liang Feng, Rui-Hui Li, Ming-Zhu Liu, Jian-Peng Wang, and Fu-Sheng Yu. Probing Direct CP Violation inΛ 0 b →P + c h−(h = π,K ) with Final-State Rescattering. 2 2026. arXiv:2602.03661

    work page arXiv 2026

  15. [15]

    Navas et al

    S. Navas et al. Review of particle physics.Phys. Rev. D, 110(3):030001, 2024. doi:10.1103/ PhysRevD.110.030001

    work page 2024

  16. [16]

    B→P and B→V Form Factors from B-Meson Light-Cone Sum Rules beyond Leading Twist.JHEP, 01:150, 2019

    Nico Gubernari, Ahmet Kokulu, and Danny van Dyk. B→P and B→V Form Factors from B-Meson Light-Cone Sum Rules beyond Leading Twist.JHEP, 01:150, 2019. arXiv:1811.00983, doi:10.1007/JHEP01(2019)150

    work page doi:10.1007/jhep01(2019)150 2019

  17. [17]

    Form factors and phenomenology of b(s) and d(s) semileptonic decays to η and η′.JHEP, 10:025, 2025

    Blaˇzenka Meli´c and M´eril Reboud. Form factors and phenomenology of b(s) and d(s) semileptonic decays to η and η′.JHEP, 10:025, 2025. arXiv:2507.13734, doi:10.1007/JHEP10(2025)025

    work page doi:10.1007/jhep10(2025)025 2025

  18. [18]

    Judd Harrison and Christine T. H. Davies. B→D* and Bs→Ds* vector, axial-vector and tensor form factors for the full q2 range from lattice QCD.Phys. Rev. D, 109(9):094515, 2024. arXiv: 2304.03137,doi:10.1103/PhysRevD.109.094515

    work page doi:10.1103/physrevd.109.094515 2024

  19. [19]

    Precision calculations of B→V form factors from soft-collinear effective theory sum rules on the light-cone.Phys

    Jing Gao, Cai-Dian L¨u, Yue-Long Shen, Yu-Ming Wang, and Yan-Bing Wei. Precision calculations of B→V form factors from soft-collinear effective theory sum rules on the light-cone.Phys. Rev. D, 101(7):074035, 2020.arXiv:1907.11092,doi:10.1103/PhysRevD.101.074035

    work page doi:10.1103/physrevd.101.074035 2020

  20. [20]

    Precision calculations of Bd,s → π, K decay form factors in soft-collinear effective theory.JHEP, 03:140, 2023.arXiv:2212.11624,doi:10.1007/JHEP03(2023)140

    Bo-Yan Cui, Yong-Kang Huang, Yue-Long Shen, Chao Wang, and Yu-Ming Wang. Precision calculations of Bd,s → π, K decay form factors in soft-collinear effective theory.JHEP, 03:140, 2023.arXiv:2212.11624,doi:10.1007/JHEP03(2023)140

    work page doi:10.1007/jhep03(2023)140 2023

  21. [21]

    $B\to V\ell^+\ell^-$ in the Standard Model from Light-Cone Sum Rules

    Aoife Bharucha, David M. Straub, and Roman Zwicky. B→Vℓ +ℓ− in the Standard Model from light-cone sum rules.JHEP, 08:098, 2016. arXiv:1503.05534, doi:10.1007/JHEP08(2016) 098

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1007/jhep08(2016 2016

  22. [22]

    McLean, C

    E. McLean, C. T. H. Davies, J. Koponen, and A. T. Lytle. Bs →D sℓν Form Factors for the full q2 range from Lattice QCD with non-perturbatively normalized currents.Phys. Rev. D, 101(7):074513, 2020.arXiv:1906.00701,doi:10.1103/PhysRevD.101.074513. 13

    work page doi:10.1103/physrevd.101.074513 2020

  23. [23]

    Decay behaviors of possibleΛ c¯c states in hadronic molecule pictures.Phys

    Chao-Wei Shen, Jia-Jun Wu, and Bing-Song Zou. Decay behaviors of possibleΛ c¯c states in hadronic molecule pictures.Phys. Rev. D, 100(5):056006, 2019. arXiv:1906.03896, doi: 10.1103/PhysRevD.100.056006

    work page doi:10.1103/physrevd.100.056006 2019

  24. [24]

    Donoghue, Xiao-Gang He, and Sandip Pakvasa

    John F. Donoghue, Xiao-Gang He, and Sandip Pakvasa. Hyperon Decays and CP Nonconservation. Phys. Rev. D, 34:833, 1986.doi:10.1103/PhysRevD.34.833

    work page doi:10.1103/physrevd.34.833 1986

  25. [25]

    Shibasis Roy, Rahul Sinha, and N. G. Deshpande. Nonleptonic beauty baryon decays and CP asymmetries based on an SU(3) -flavor analysis.Phys. Rev. D, 101(3):036018, 2020. arXiv: 1911.01121,doi:10.1103/PhysRevD.101.036018. 14

    work page doi:10.1103/physrevd.101.036018 2020