Pith. sign in

REVIEW 3 major objections 4 minor 41 references

The width of $f_{0}(980)$ in isospin-symmetry-breaking decays

T0 review · 3 major / 4 minor · reviewed 2026-08-11 · deepseek-v4-flash

Pith's one-line read The paper simultaneously fits five $\pi\pi$ invariant mass spectra from isospin-symmetry-breaking decays and extracts a sharp $f_0(980)$ width of $11.4 \pm 1.1$ MeV, with couplings that favor a kaon-molecule or quark-antiquark internal…

desk verdict A competent re-analysis that sharpens the f0(980) width and couplings but never tests the triangle-singularity alternative it cites, leaving the model-preference conclusion conditional. read the letter →

arxiv 2412.12855 v1 pith:URFK7QSG submitted 2024-12-17 hep-ph

classification hep-ph
keywords f0(980)isospinsymmetrybreakingsimultaneousfitFlattéformulaBreit-Wignerresonancecouplingconstantsscalarmesonstructure
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

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

The reading

The paper aims to establish that the anomalously narrow width of the $f_0(980)$ meson seen in five isospin-symmetry-breaking decay channels is a genuine resonance property, and that the extracted couplings can discriminate among competing internal-structure pictures. A simultaneous fit to all five published $\pi\pi$ invariant mass distributions yields a mass of $990.0 \pm 0.4 \pm 0.1$ MeV/$c^2$ and a width of $11.4 \pm 1.1 \pm 0.9$ MeV, sharply below the $40$–$100$ MeV range usually quoted for $f_0(980)$. Replacing the line shape with a Flatté formula gives coupling constants $g_{f\pi\pi} = 0.46 \pm 0.03$ and $g_{fK\bar{K}} = 1.24 \pm 0.32$. Comparing the joint confidence region of these couplings with model predictions, the paper concludes the data support a $K\bar{K}$ molecule or a quark-antiquark state and disfavor tetraquark and hybrid models. If correct, this would pin down the mass and width of $f_0(980)$ in these processes to a precision far better than current averages and narrow the list of plausible internal structures.

What carries the argument

The central objects are two parameterizations of the resonance line shape: the non-relativistic Breit-Wigner amplitude $\mathrm{BW}_f = \Gamma_{\rm el}/2\,/\,(m_f - \sqrt{s} - i\Gamma_f/2)$, convolved with a Gaussian mass resolution for each channel, and the energy-dependent Flatté propagator $G_f = 1/[s - m_f^2 + i\sqrt{s}\,(\Gamma_{f\pi\pi}(s) + \Gamma_{fK\bar{K}}(s))]$, with partial widths built from two-body phase-space factors $\rho(A,B)$. These line shapes carry the argument because a simultaneous likelihood fit over the five channels forces a single mass and width (or a single pair of couplings) to reproduce all the observed narrow peaks, thereby converting separate peak sightings into one resonance hypothesis.

What would settle it

Refit the five $\pi\pi$ invariant mass spectra with an amplitude that includes both the $f_0(980)$ Breit-Wigner and the triangle-singularity mechanism; if the intrinsic width then leaves the 11 MeV value and moves toward the conventional 40–100 MeV range, or if the best-fit width differs between the $\eta(1405)$, $f_1(1285)$, and $\chi_{c1}$ production channels, the single-resonance interpretation is falsified.

Watch

Extended reading notes

Core claim

The central claim is that five independent $\pi\pi$ invariant mass distributions from the isospin-breaking decays $\eta(1405)\to \pi^0 f_0(980)$, $f_1(1285)\to \pi^0 f_0(980)$, and $\chi_{c1}\to \pi^0 f_0(980)$, each showing a narrow peak of roughly 10 MeV, are all described by a single resonance with $M = 990.0 \pm 0.4(\mathrm{stat}) \pm 0.1(\mathrm{syst})$ MeV/$c^2$ and $\Gamma = 11.4 \pm 1.1(\mathrm{stat}) \pm 0.9(\mathrm{syst})$ MeV. The same data, fitted with a Flatté parameterization, give $g_{f\pi\pi} = 0.46 \pm 0.03$ and $g_{fK\bar{K}} = 1.24 \pm 0.32$. In the joint confidence region of these two couplings, the model predictions for a $K\bar{K}$ molecule and a quark-antiquark state lie inside the $5\sigma$ region, while tetraquark and quark-antiquark-gluon hybrid predictions lie well outside, leading the authors to conclude that the data favor the former two pictures. The analysis keeps the detector mass resolutions fixed from Monte Carlo simulations and uses polynomial backgrounds for each channel.

Load-bearing premise

The fit assumes the narrow peak seen in these isospin-breaking decays is the $f_0(980)$ resonance line shape, not a distinct peak generated by the triangle-singularity mechanism, which the paper cites but does not include in the fit.

Editorial extensions

If this is right

  • The $f_0(980)$ width in isospin-symmetry-breaking decays, about 11 MeV, is an order of magnitude smaller than the conventional 40–100 MeV estimate, so any successful model of $f_0(980)$ must be able to produce such a narrow width in these channels.
  • Because one common mass and width describe all five spectra, the narrow peaks are statistically consistent with being the same resonance in every process rather than independent kinematic effects.
  • The Flatté coupling ratio $g_{fK\bar{K}}/g_{f\pi\pi} \approx 2.7$ falls in the region predicted by the $K\bar{K}$-molecule and quark-antiquark models and far from the tetraquark and hybrid predictions, narrowing the candidate internal structures.
  • The joint confidence regions of the mass-width and couplings can be used as fixed inputs in future Dalitz-plot analyses of decays of $\eta(1405)$, $f_1(1285)$, and $\chi_{c1}$.
  • The paper notes that $a_0(980)$-$f_0(980)$ mixing alone cannot account for the large isospin-breaking ratios, so the same five spectra also constrain whatever additional production mechanism feeds these decays.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • The fit excludes a triangle-singularity amplitude, yet the paper cites the triangle mechanism as a known source of a narrow peak near the $K\bar{K}$ threshold; if that mechanism contributes, the quoted $M$ and $\Gamma$ are effective line-shape parameters rather than the $f_0(980)$ pole parameters. A testable extension is to fit the same data with a coherent sum of Breit-Wigner and triangle-singula
  • The extracted couplings could be checked against a dispersive pole analysis of the same invariant mass spectra, which would give pole positions and residues without assuming a Flatté form; agreement would strengthen the claim that the fitted couplings are model-independent.
  • Comparing the best-fit width across the three production parents ($\eta(1405)$, $f_1(1285)$, $\chi_{c1}$) with larger statistics would test whether the narrow line shape is universal; a width that changes with the production reaction would indicate that the peak is not a single resonance property.
  • A stronger model discrimination would use the model predictions with their theoretical uncertainties, which the current comparison omits; the joint confidence regions could then assign quantitative likelihoods to each internal-structure hypothesis.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 4 minor

Summary. The paper performs a simultaneous fit to five ππ invariant-mass distributions from BESIII isospin-symmetry-breaking decays, using a non-relativistic Breit-Wigner convolved with a Gaussian resolution to extract M=990.0±0.4(stat)±0.1(syst) MeV/c² and Γ=11.4±1.1(stat)±0.9(syst) MeV. A Flatté parameterization is then used on the same data to extract g_fππ=0.46±0.03 and g_fKK=1.24±0.32. Comparing these couplings with model predictions from Ref. [28], the authors conclude that the data favor the KK-molecule and qqbar pictures over tetraquark and hybrid pictures. The central claim is that these are the properties of the f0(980) in isospin-symmetry-breaking decays and that they discriminate among models of its internal structure.

Significance. If the line-shape assumption is correct, the simultaneous fit is a useful precision step: it reduces the statistical uncertainty on the f0(980) width compared with the individual BESIII results, and the paper reports goodness-of-fit values for each channel. The couplings extracted from the Flatté fit would provide a quantitative constraint on model predictions. However, the model-discrimination conclusion inherits a load-bearing assumption that is flagged but not tested in the paper itself: the narrow peak in these channels may contain a substantial triangle-singularity contribution, in which case the fitted width and couplings are effective parameters of the chosen Breit-Wigner/Flatté parameterization rather than intrinsic f0(980) pole parameters. The paper would be a solid contribution if it could demonstrate that the triangle-singularity alternative is negligible or distinguishable; as it stands, the main interpretive claim is not established.

major comments (3)
  1. [Sections I, II, and III]
  2. [Section IV, Table II]
  3. [Section II, data input]
minor comments (4)
  1. [Section II, Figure 2]
  2. [Equation (1)]
  3. [Section III, Equation (3)]
  4. [Abstract and Section V]

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity: the fitted masses, widths, and couplings are extracted from external BESIII data and compared with independent model predictions from Ref. [28].

full rationale

The paper's derivation chain is a standard data-fitting analysis: it takes external BESIII invariant-mass histograms, fits them with a non-relativistic Breit-Wigner (Eq. 1) and then with a Flatté parameterization (Eq. 3), and extracts mass, width, and coupling constants. None of these extracted quantities is relabeled as a prediction made from first principles; they are fit parameters obtained from the data. The theoretical model predictions in Table II and Figure 3 are taken from Ref. [28] (Jia-Jun Wu et al.), which is independent prior work not authored by the present authors, so the model comparison is not back-fitted to the same data. The paper does not invoke any uniqueness theorem or load-bearing self-citation, and the Flatté/Breit-Wigner line shapes are standard parameterizations adopted explicitly as assumptions, not smuggled in as derived results. The acknowledged triangle-singularity mechanism (Refs. [30-33]) is a potentially important alternative line-shape interpretation, and its omission is a scientific robustness concern, but it does not make the fitting procedure circular: the fitted values remain well-defined parameters of the chosen parameterization. No specific equation or step reduces to its own input by construction, so no circularity is present.

Assumptions & free parameters 5 free parameters · 5 assumptions · 0 invented entities

The central claim rests on a standard resonance parametrization plus a background model, applied to previously published spectra. The main free parameters are the mass, width, and two couplings. The most consequential assumption is that the line shape is simple Breit-Wigner or Flatte, which is in direct tension with the triangle singularity alternative discussed in the paper's own introduction.

free parameters (5)
  • m_f (mass of f0(980)) = 990.0 +/- 0.4 MeV/c^2 in BW fit; fixed to PDG in Flatte fit
    The mass is left free in the simultaneous Breit-Wigner fit and determined from the data. In the Flatte fit it is fixed to the PDG nominal value, as stated in Section III.
  • Gamma_f (total width of f0(980)) = 11.4 +/- 1.1 MeV
    The width is a free parameter in the Breit-Wigner simultaneous fit to the five spectra.
  • g_{f pi pi} = 0.46 +/- 0.03
    Coupling of f0(980) to pi pi, extracted from the Flatte fit to the same spectra in Section III.
  • g_{f K Kbar} = 1.24 +/- 0.32
    Coupling of f0(980) to K Kbar, extracted from the Flatte fit in Section III.
  • Per-channel signal and background yields (N_f, N_bkg) and background polynomial coefficients
    Each of the five channels has a signal yield, a background yield, and Chebyshev coefficients that are adjusted in the fit; values are not individually reported.
assumptions (5)
  • domain assumption The f0(980) signal line shape is described by a non-relativistic Breit-Wigner or a Flatte formula.
    Used in Section II Eq. (1) and Section III Eq. (3). The triangle singularity mechanism cited in the introduction is a competing shape not included in the fit.
  • domain assumption The background in each decay channel is a first- or second-order Chebyshev polynomial.
    Section II states the polynomial order matches the fit in the BESIII papers; no independent justification for this background form is given.
  • domain assumption The detector mass resolution is a Gaussian with fixed widths from Monte Carlo simulation.
    Section II and Table I: resolutions are fixed during the fit. The accuracy of the MC resolution is assumed.
  • domain assumption The binned data digitized from the BESIII figures accurately represent the underlying spectra.
    Section II: 'We acquire the binned data, presented as histogram data, from the aforementioned published results.' The digitization errors are not quantified.
  • domain assumption The theoretical coupling predictions from Ref [28] are reliable and applicable to the same Flatte parametrization.
    Section IV compares the fitted couplings with the model predictions from Wu and Zou (Ref [28]) at face value; the paper does not propagate uncertainties from those model calculations.

how reviews work

0 comments
Cite this review

Pith. "Pith review of The width of $f_{0}(980)$ in isospin-symmetry-breaking decays." pith.science (2026). https://pith.science/paper/URFK7QSG

@misc{pith2026241212855,
  author       = {Pith},
  title        = {Pith review of: The width of $f_0(980)$ in isospin-symmetry-breaking decays},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/URFK7QSG}},
  note         = {Machine review of arXiv:2412.12855}
}
abstract

The scalar meson $f_{0}(980)$ has long posed a perplexing puzzle within the realm of light hadron physics. Conventionally, its mass and width in normal decay processes have been estimated as $M=990\pm20$~MeV/$c^2$ and $\Gamma=40-100$~MeV, respectively. Theoretical explanations regarding the internal structure of $f_{0}(980)$ range from it being a conventional quark-antiquark meson to a tetraquark state, a $K\overline{K}$ molecule, or even a quark-antiquark gluon hybrid. However, a definitive consensus has remained elusive over a considerable duration. Recent observations by the BESIII experiment have unveiled anomalously narrow widths of $f_{0}(980)$ in five independent isospin-symmetry-breaking decay channels. Harnessing these experimental findings, we performed a simultaneous fit to the $\pi\pi$ invariant mass distributions, resulting in a refined determination of the mass and width in isospin-symmetry-breaking decays as $M=990.0\pm0.4(\text{stat})\pm0.1(\text{syst})$~MeV/$c^2$ and $\Gamma=11.4\pm1.1(\text{stat})\pm0.9(\text{syst})$~MeV, respectively. Here, the first errors are statistical and the second are systematic. Furthermore, by employing the parameterized Flatt\'{e} formula to fit the same $\pi\pi$ invariant mass distributions, we ascertained the values of the two coupling constants, $g_{f\pi\pi}$ and $g_{fK\overline{K}}$, as $g_{f\pi\pi}=0.46\pm0.03$ and $g_{fK\overline{K}}=1.24\pm0.32$, respectively. Based on the joint confidence regions of $g_{f\pi\pi}$ and $g_{fK\overline{K}}$, we draw the conclusion that the experimental data exhibit a propensity to favor the $K\overline{K}$ molecule model and the quark-antiquark ($q\bar{q}$) model, while offering relatively less support for the tetraquarks ($q^{2}\bar{q}^{2}$) model and the quark-antiquark gluon ($q\bar{q}g$) hybrid model.

Figures

Figures reproduced from arXiv: 2412.12855 by the authors.

Figure 1
Figure 1. FIG. 1. The Feynman diagram of the hadronic level: ( [PITH_FULL_IMAGE:figures/full_fig_p004_1.png] view at source ↗
Figure 2
Figure 2. FIG. 2. The simultaneous fit to the [PITH_FULL_IMAGE:figures/full_fig_p007_2.png] view at source ↗
Figure 3
Figure 3. FIG. 3. The joint confidence regions of the two coupling const [PITH_FULL_IMAGE:figures/full_fig_p011_3.png] view at source ↗

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

41 extracted references · 40 canonical work pages

  1. [28]

    Investigation o f a0–f0 mixing,

    C. Hanhart, B. Kubis, and J. R. Pelaez, “Investigation o f a0–f0 mixing,” Phys. Rev. D, 76, 074028 (2007)

  2. [1]

    40± 0. 07± 0. 14± 0. 07, which is less than 1. 0%. Obviously, the a0 0(980)-f0(980) mixing mech- anism can not completely describe the large isospin-symmetry-brea king ratio in the decays of η(1405) → π 0f0(980) → π 0π +π −/π 0π 0π 0 and f1(1285) → π 0f0(980) → π 0π +π −/π 0π 0π 0. (a) (b) FIG. 1. The Feynman diagram of the hadronic level: ( a) The diagra...

  3. [2]

    The φ(1020) → π 0π 0γ decay,

    M. N. Achasov et al. (SND Collaboration), “The φ(1020) → π 0π 0γ decay,” Phys. Lett. B 485, 349-356 (2000)

  4. [3]

    Review of Particle Physics,

    R. L. Workman et al. (Particle Data Group),“Review of Particle Physics,” Prog. Theor. Exp. Phys. 2022, 083C01 (2022)

  5. [4]

    Resonances in J/ψ → φπ +π − and φK +K − ,

    M. Ablikim et al. (BESIII Collaboration), “Resonances in J/ψ → φπ +π − and φK +K − ,” Phys. Lett. B , 607, 243–253 (2005)

  6. [5]

    Study of the decay φ → π 0π 0γ with the KLOE detector,

    A. Aloisio et al. (KLOE Collaboration), “Study of the decay φ → π 0π 0γ with the KLOE detector,” Phys. Lett. B , 537, 21-27 (2002)

  7. [6]

    Pion- pion scattering amplitude IV. Improved analysis with once s ubtracted Roy-like equations up to 1100 MeV,

    R. Garc ´ ıa-Mart ´ ın, R. Kami´ nski, J. R. Pel´ aez, J. Ruizde Elvira and F. J. Yndur´ ain, “Pion- pion scattering amplitude IV. Improved analysis with once s ubtracted Roy-like equations up to 1100 MeV,” Phys. Rev. D , 83, 074004 (2011). 12

  8. [7]

    e+e− → K +K −π +π − , K +K −π 0π 0 and K +K −K +K − cross sections measured with initial-state radiation,

    B. Aubert et al. (BABAR Collaboration), “ e+e− → K +K −π +π − , K +K −π 0π 0 and K +K −K +K − cross sections measured with initial-state radiation,” Ph ys. Rev. D , 76, 012008 (2007)

Show all 41 references
  1. [8]

    Review of Particle Physics,

    K. A. Olive et al. (Particle Data Group), “Review of Particle Physics,” Chin. Phys. C, 38, 090001 (2014)

  2. [9]

    Precise Determination of the f0(600) and f0(980) Pole Parameters from a Dispersive Data Analysis,

    R. Garc ´ ıa-Mart ´ ın, R. Kami´ nski, J. R. Pel´ aez, and J. Ruiz de Elvira, “Precise Determination of the f0(600) and f0(980) Pole Parameters from a Dispersive Data Analysis,” Phy s. Rev. Lett. , 107, 072001 (2011)

  3. [10]

    Observation of the isospin-viol ating decay J/ψ → φπ 0f0(980),

    M. Ablikim et al. (BESIII Collaboration), “Observation of the isospin-viol ating decay J/ψ → φπ 0f0(980),” Phys. Rev. D, 92, 012007 (2015)

  4. [11]

    1(stat) ± 0

    4 ± 1. 1(stat) ± 0. 9(syst) MeV, respectively. Here, the first errors are statistica l and the second are systematic. III. DETERMINA TION OF COUPLING CONST ANTS gf ππ AND gf K K Because the f0(980) can decay to both ππ and KK final states, it can be described by the Flatt´ e for...

  5. [12]

    First Observation of η(1405) Decays into f0(980)π 0,

    M. Ablikim et al. (BESIII Collaboration), “First Observation of η(1405) Decays into f0(980)π 0,” Phys. Rev. Lett., 108, 182001 (2012)

  6. [13]

    Observation of a0 0(980)−f0(980) Mixing,

    M. Ablikim et al. (BESIII Collaboration), “Observation of a0 0(980)−f0(980) Mixing,” Phys. Rev. Lett., 121, 022001 (2018)

  7. [14]

    On a Search for Four Q uark States in Radiative Decays of φ Meson,

    N. N. Achasov and V. N. Ivanchenko, “On a Search for Four Q uark States in Radiative Decays of φ Meson,” Nucl. Phys. B, 315, 465 (1989)

  8. [15]

    qq − qq system in a potential model,

    J. Weinstein and N. Isgur, “qq − qq system in a potential model,” Phys. Rev. D 27, 588 (1983)

  9. [16]

    K K molecules,

    J. Weinstein and N. Isgur, “ K K molecules,” Phys. Rev. D, 41, 2236 (1990)

  10. [17]

    Ishida et al

    S. Ishida et al. , In Proceedings of the 6th International Conference on Hadr on Spectroscopy, Manchester, United Kingdom, 10th-14th July 1995 (World Sci entific, Singapore, 1995), p.454

  11. [18]

    S∗-δ0 mixing as a threshold phe- nomenon,

    N. N. Achasov, S. A. Devyanin, and G. N. Shestakov, “ S∗-δ0 mixing as a threshold phe- nomenon,” Phys. Lett. B , 88, 367-371 (1979)

  12. [19]

    Mixing of the f0 and a0 scalar mesons in threshold photopro- duction,

    B. Kerbikov and F. Tabakin, “Mixing of the f0 and a0 scalar mesons in threshold photopro- duction,” Phys. Rev. C, 62, 064601 (2000)

  13. [20]

    Proposed Search for a0 0(980) − f0(980) Mixing in Polar- ization Phenomena,

    N. N. Achasov and G. N. Shestakov, “Proposed Search for a0 0(980) − f0(980) Mixing in Polar- ization Phenomena,” Phys. Rev. Lett., 92, 182001 (2004)

  14. [21]

    Manifestation of the a0 0(980) − f0(980) mixing in the reaction π −p → ηπ 0n on a polarized target,

    N. N. Achasov and G. N. Shestakov, “Manifestation of the a0 0(980) − f0(980) mixing in the reaction π −p → ηπ 0n on a polarized target,” Phys. Rev. D, 70, 074015 (2004)

  15. [22]

    On the possibility of observation of a0-f0 mixing in the pn → da0 reaction,

    A. E. Kudryavtsev and V. E. Tarasov, “On the possibility of observation of a0-f0 mixing in the pn → da0 reaction,” JETP Lett. , 72, 410 (2000)

  16. [23]

    Angular asymmetries in the reactions pp → dπ +η and pn → dπ 0η and a0-f0 mixing,

    A. E. Kudryavtsev, V. E. Tarasov, J. Haidenbauer, C. Han hart, and J. Speth, “Angular asymmetries in the reactions pp → dπ +η and pn → dπ 0η and a0-f0 mixing,” Phys. At. Nucl., 66, 1946 (2003). 13

  17. [24]

    Aspects of a0-f0 mixing in the reaction pn → da0,

    A. E. Kudryavtsev, V. E. Tarasov, J. Haidenbauer, C. Han hart, and J. Speth, “Aspects of a0-f0 mixing in the reaction pn → da0,” Phys. Rev. C, 66, 015207 (2002)

  18. [25]

    a0(980)-f0(980) mixing and isospin violation in the reactions pN → da0, pd → 3 He/ 3Ha 0 and dd → 4 Hea 0,

    V. Y. Grishina, L. A. Kondratyuk, M. B¨ uscher, W. Cassin g, and H. Str¨ oher, “a0(980)-f0(980) mixing and isospin violation in the reactions pN → da0, pd → 3 He/ 3Ha 0 and dd → 4 Hea 0,” Phys. Lett. B, 521, 217-224 (2001)

  19. [26]

    Isospin breaking exposed in f0(980)-a0(980) mixing,

    F. E. Close and A. Kirk, “Isospin breaking exposed in f0(980)-a0(980) mixing,” Phys. Lett. B, 489, 24-28 (2000)

  20. [27]

    Large isospin mixing in φ radiative decay and the spatial size of the f0(980)-a0(980) mesons,

    F. E. Close and A. Kirk, “Large isospin mixing in φ radiative decay and the spatial size of the f0(980)-a0(980) mesons,” Phys. Lett. B, 515, 13-16 (2001)

  21. [29]

    Possibility of measuring a0 0(980)-f0(980) mixing from J/ψ → φa 0 0(980),

    J. J. Wu, Q. Zhao and B. S. Zou, “Possibility of measuring a0 0(980)-f0(980) mixing from J/ψ → φa 0 0(980),” Phys. Rev. D, 75, 114012 (2007)

  22. [30]

    Study of a0 0(980)−f0(980) mixing froma0 0(980) → f0(980) transition,

    J. J. Wu and B. S. Zou, “Study of a0 0(980)−f0(980) mixing froma0 0(980) → f0(980) transition,” Phys. Rev. D, 78, 074017 (2008)

  23. [31]

    Study of a0 0(980) − f0(980) mixing,

    M. Ablikim et al. (BESIII Collaboration), “Study of a0 0(980) − f0(980) mixing,” Phys. Rev. D, 83, 032003 (2011)

  24. [32]

    Puzzle of Ano malously Large Isospin Violations in η(1405/ 1475) → 3π ,

    J.-J. Wu, X.-H. Liu, Q. Zhao and B.-S. Zou, “Puzzle of Ano malously Large Isospin Violations in η(1405/ 1475) → 3π ,” Phys. Rev. Lett., 108, 081803 (2012)

  25. [33]

    Isos pin breaking and f0(980)-a0(980) mixing in the η(1405) → π 0f0(980) reaction,

    F. Aceti, W. H. Liang, E. Oset, J. J. Wu and B. S. Zou, “Isos pin breaking and f0(980)-a0(980) mixing in the η(1405) → π 0f0(980) reaction,” Phys. Rev. D, 86, 114007 (2012)

  26. [34]

    Internal particle width effects on the triangle singularity mechanism in the study of the η(1405) andη(1475) puzzle,

    Meng-Chuan Du and Qiang Zhao, “Internal particle width effects on the triangle singularity mechanism in the study of the η(1405) andη(1475) puzzle,” Phys. Rev. D, 100, 036005 (2019)

  27. [35]

    Vertex corre ctions due to the triangle singu- larity mechanism in the light axial vector meson couplings t oK ∗ K+c.c.,

    Meng-Chuan Du, Yin Cheng, and Qiang Zhao, “Vertex corre ctions due to the triangle singu- larity mechanism in the light axial vector meson couplings t oK ∗ K+c.c.,” Phys. Rev. D, 106, 054019 (2022)

  28. [36]

    Role of a triangle singularity in the γp → K +Λ(1405) reaction,

    En Wang, Ju-Jun Xie, Wei-Hong Liang, Feng-Kun Guo, and E ulogio Oset, “Role of a triangle singularity in the γp → K +Λ(1405) reaction,” Phys. Rev. C, 95, 015205 (2017)

  29. [37]

    Triangle singularities in J/ψ → ηπ 0φ and π 0π 0φ,

    Hao-Jie Jing, Shuntaro Sakai, Feng-Kun Guo and Bing-So ng Zou, “Triangle singularities in J/ψ → ηπ 0φ and π 0π 0φ,” Phys. Rev. D, 100, 114010 (2019). 14

  30. [38]

    Trian gle singularity in the B− → K −π 0X(3872) reaction and sensitivity to the X(3872) mass,

    Shuntaro Sakai, Eulogio Oset, and Feng-Kun Guo, “Trian gle singularity in the B− → K −π 0X(3872) reaction and sensitivity to the X(3872) mass,” Phys. Rev. D, 101, 054030 (2020)

  31. [39]

    Trian gle singularity mechanism for the pp → π +d fusion reaction,

    Natsumi Ikeno, Raquel Molina, and Eulogio Oset, “Trian gle singularity mechanism for the pp → π +d fusion reaction,” Phys. Rev. C, 104, 014614 (2021)

  32. [40]

    Λ(1405) m ediated triangle singularity in the K −d → pΣ − reaction,

    A. Feijoo, R. Molina, L. R. Dai, Eulogio Oset, “Λ(1405) m ediated triangle singularity in the K −d → pΣ − reaction,” Eur. Phys. J., 82, 1028 (2022)

  33. [41]

    Verkerke and D

    W. Verkerke and D. Kirkby, The RooFit toolkit for data mo deling. Computing in High Energy and Nuclear Physics (CHEP03), La Jolla, California, USA, 24th-28th March 2003.[ arXiv:physics/0306116v1 [physics.data-an] 2003. ] 15

Pith tools

Reviewed August 11, 2026 · model on record in the stance chip above.