Pith. sign in

REVIEW 4 major objections 5 minor 47 references

Heavy tetraquarks in the hyperspherical approach

T0 review · 4 major / 5 minor · reviewed 2026-08-04 · deepseek-v4-flash

Pith's one-line read This paper claims that a one-dimensional hyperspherical equation, obtained by averaging over angles, predicts ground-state masses of fully heavy tetraquarks with about 0.1 GeV accuracy.

desk verdict A useful hyperspherical cross-check on fully heavy tetraquark masses, but the missing B = -0.8 GeV constant in the solved equation makes the absolute scale ambiguous. read the letter →

arxiv 2509.10940 v1 pith:C5O6FZ2O submitted 2025-09-13 hep-ph

classification hep-ph PACS 12.39.Ki14.40.Pq
keywords tetraquarkshypersphericalmethodhyperradialapproximationheavyquarksquarkmodelBreitHamiltonianhyperfinesplittingmassspectrum
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 tries to establish that the hyperradial approximation—reducing the four-quark problem to a single radial Schrödinger equation after angular averaging—can reproduce the masses of heavy tetraquarks such as (cc\bar c\bar c), (bb\bar b\bar b), and (cc\bar b\bar c). It predicts ground-state masses of 5.86, 6.02, and 6.35 GeV for the all-charm tetraquark in the 0++, 1+-, and 2++ channels, with similar predictions for the all-beauty and mixed states. The authors argue that the resulting analytic wave function is simple enough to compute hyperfine splitting and relativistic corrections, and that the approach gives results comparable to other quark-model calculations while offering a transparent physical picture.

What carries the argument

The central object is the hyperradius $R$, defined by $R^2 = \rho^2 + \lambda^2 + \sigma^2$ in Jacobi coordinates, and the hyperspherical angular momentum $K$. In the hyperradial approximation one sets $K=0$, so the wave function depends only on $R$ and the potential is replaced by its angular average, giving $\langle 1/\rho \rangle = \frac{35}{16R}$ and $\langle \rho \rangle = \frac{35R}{64}$. This leads to a one-dimensional equation with effective Coulomb and linear constants $a = \frac{175}{12\sqrt{2}} \alpha_s \sqrt{m}$ and $b = \frac{175}{32\sqrt{2}} A \sqrt{m}$. The solution is obtained with a variational wave function of the form $\chi(x) = \left[ \frac{2}{9} q p^{9/q} / \Gamma(9/q) \right]^{1/2} x^4 e^{-p x^q}$, whose Airy-function asymptotics match the confining potential. This wave function is then used to compute spin-spin hyper

What would settle it

Measure the mass of the 0++ fully charmed tetraquark; if it differs from 5.86 GeV by more than the stated ~0.1 GeV error, the angular-averaging step fails. Alternatively, a hyperspherical calculation that retains $K>0$ harmonics and shifts the binding energy by more than ~0.03 GeV would falsify the $K=0$ truncation.

Watch

Extended reading notes

Core claim

Within the quark model, the paper reduces the four-body Schrödinger equation for heavy tetraquarks to a one-dimensional equation for a wave function that depends only on the hyperradius $R$, after averaging the potential over the angles of a nine-dimensional hypersphere. The equation contains an effective Coulomb attraction $a/R$ and a linear confining term $bR$, with $a$ and $b$ expressed in terms of quark masses and the strong coupling constant. Solving this equation numerically and with a trial function of the form $\chi(x) \propto x^4 \exp(-p x^q)$, the authors find a nonrelativistic binding energy of 0.380 GeV for (cc\bar c\bar c), matching the numerical solution. Adding relativistic kinetic corrections, rec

Load-bearing premise

The prediction rests on assuming the four-quark wave function is independent of the angular variables in nine-dimensional space, so the real interaction is replaced by its angular average; the paper itself notes a 0.03 GeV binding-energy difference with its variational calculation, which may reflect small angular dependence.

Editorial extensions

If this is right

  • If the hyperradial predictions are correct, the 0++ all-charm tetraquark should appear near 5.86 GeV, with a hyperfine splitting of about 0.16 GeV between the 0++ and 1+- states.
  • The simple analytic wave function (26) can be used to estimate production and decay matrix elements, such as tetraquark production in rare Higgs decays.
  • The ordering of states (0++ below 1+- below 2++) is a direct consequence of the spin-spin Hamiltonian, providing a clear experimental signature.
  • The 0.03 GeV difference between the hyperradial and variational binding energies suggests that including small angular dependence in the wave function would shift the masses by at most a few tens of MeV.
  • The method, with its fixed quark-model parameters, yields masses that fall within the range of other quark-model predictions, supporting the search for these states at colliders.

Reading between the lines

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

  • Inference: If the hyperradial approximation is accurate, the same reduction could be applied to excited tetraquark states by retaining K>0 hyperspherical harmonics; the centrifugal term -6/(μR^2) already present would then shift and split the spectrum in a predictable way.
  • Inference: The predicted 0++ all-charm mass near 5.86 GeV lies below the J/ψ pair threshold, suggesting a narrow state, whereas the 2++ at 6.35 GeV lies above it; this threshold crossing is a testable line-shape prediction not explicitly stated in the paper.
  • Inference: The value of the tetraquark wave function at zero separation (Ψ_T(0)=0.09 GeV^{9/2}) directly controls production rates; a future measurement of exotic tetraquark production in Higgs decays would provide a quantitative test of both the wave function and the hyperradial approach.
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

4 major / 5 minor

Summary. The paper computes masses of fully heavy tetraquarks (cc\bar c\bar c), (bb\bar b\bar b), and (cc\bar b\bar b) in the ground states 0++, 1+-, 2++ using the hyperspherical approach. The four-body Schrödinger equation is reduced to a one-dimensional hyperradial equation by assuming K=0 and averaging over the nine-dimensional angular variables. The hyperradial equation is solved numerically and variationally, with good mutual agreement (E0=0.380 vs 0.382 GeV for (cc\bar c\bar c)). Hyperfine splitting is computed from one-gluon-exchange and confinement spin-spin terms, and relativistic and recoil corrections are added. The final masses are listed in Table I, e.g., 5.86, 6.02, and 6.35 GeV for (cc\bar c\bar c).

Significance. If the calculation is correct, it provides a simple analytical framework for fully heavy tetraquark masses and wave functions, with predictions that can be compared with LHCb, CMS, and ATLAS searches. A strength of the paper is that all model parameters are taken from earlier meson calculations rather than fitted to tetraquark data, so the tetraquark masses are genuine predictions. The numerical and variational solutions agree well, and the analytical wave function (26) allows transparent computation of hyperfine and relativistic corrections. The main weakness is that the K=0 hyperradial approximation is uncontrolled, and there is an apparent internal inconsistency in the treatment of the constant term B in the confinement potential.

major comments (4)
  1. [Section II, Eq. (6) and Section III, Eq. (17)] The confinement potential in Eq. (6) contains a constant term B=-0.8 GeV, but the hyperradial Schrödinger equation (17) contains no such constant. Averaging a constant over angles gives the same constant, so if B is part of the Hamiltonian it shifts every eigenvalue by -0.8 GeV. With B included literally, the (cc\bar c\bar c) 0++ mass in Table I would be about 5.06 GeV, far outside the claimed ±0.1 GeV error. The manuscript does not state that B is absorbed into the quark masses or cancelled by another term. This is a load-bearing internal inconsistency that must be resolved.
  2. [Section III, Eqs. (14)-(18)] The K=0 hyperradial approximation replaces the potential by its angular average and assumes the wave function depends only on R. No convergence check with K>0 components is provided. The paper itself notes a 0.03 GeV difference from the variational result, which it attributes to a possible small dependence of the wave function on angles. This approximation is central not only for the binding energy but also for the delta-function matrix elements used in Section IV for hyperfine splitting. Without a quantitative estimate of the angular dependence, the stated theoretical error of 0.1 GeV appears optimistic.
  3. [Section V, Eqs. (42), (44), (46), (48)] The relativistic, recoil, and contact corrections are presented as results of analytical calculations, but no derivation or intermediate steps are given. The text states that these corrections are 'numerically large' and enter with negative sign, so they materially affect Table I. The reader cannot verify the formulas, and Eq. (42) contains an unusual coefficient (20337) that may indicate a typo. The authors should provide at least a derivation outline and numerical cross-checks of these matrix elements.
  4. [Section III, Eq. (20) and Section IV, Eq. (34)] The effective constants a and b are given explicitly only for tetraquarks with identical quark masses, and the hyperfine coefficient κ is also written for the equal-mass case. However, Table I includes (cc\bar b\bar b), where quark masses differ. The paper does not state how the angular averages, the reduced masses, and the delta-function matrix elements are generalized to unequal masses. Without this, the (cc\bar b\bar b) entries in Table I are not supported by the equations presented.
minor comments (5)
  1. [Abstract] Typo: 'Schroedinger' should be 'Schrödinger'.
  2. [Section III, Eq. (33)] The notation '<δ(r12)>=<δ(ρ)>= ... =δ=0.0846257426 GeV^3' is confusing because δ denotes both the delta function and the numerical value. Use a separate symbol for the matrix element.
  3. [Section IV, Eqs. (30)-(32)] The spin wave functions are labeled χ^{11}_{00}, χ^{11}_{11}, χ^{11}_{22}; the second subscript should denote the total spin projection, not the total spin. The notation is inconsistent and should be clarified.
  4. [Section V, Eq. (42)] The coefficient 20337 inside the parenthesis appears suspicious; please verify the arithmetic. It would also help to state the units of p explicitly in Eq. (42).
  5. [Section III, Eq. (20)] The statement that a and b do not depend on μ is made only for the equal-mass case. For the unequal-mass tetraquark, the derivation should be spelled out.

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity: the tetraquark masses are genuine model predictions from meson-calibrated parameters; self-citations are comparative rather than load-bearing.

full rationale

The central derivation is self-contained in the relevant sense: the Hamiltonian in Eqs. (5)-(6) uses quark masses, α_s values, and confinement constants taken from meson spectroscopy ([40]), not fitted to tetraquark data, and the hyperradial equation (17) is then solved numerically and variationally to produce the masses in Table I. No parameter is defined in terms of the predicted tetraquark masses, and no listed tetraquark mass is reused as an input in the same chain. The self-citations to the authors' earlier works ([23], [42], [43]) are used only for comparison of binding energies and wave-function values, not as the justification for the new mass values, so they are not load-bearing. The most serious flagged issue is not a circularity: Eq. (6) fixes "B = −0.8 GeV" as a constant in the confinement potential, but Eq. (17) and its scaled form (19) contain no constant term, only +a/R − bR − 6/(µR^2). If B were included literally, every eigenvalue in Table I would shift by about −0.8 GeV, which would be an internal-consistency/correctness problem with the stated Hamiltonian, not a reduction of the prediction to its own inputs. Likewise, the hyperradial K=0 assumption is an approximation, honestly acknowledged by the authors' remark that the 0.03 GeV difference from [23] "may mean that real tetraquark wave function has a small dependence on angles," but approximating a wave function is not circular reasoning. Overall, the paper's predictions do not reduce by construction to fitted outputs or to a self-citation chain.

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

The central claim rests on a nonrelativistic quark model with parameters imported from meson fits, plus the uncontrolled hyperradical approximation. No new entities are introduced. The variational parameters are optimized, not free.

free parameters (5)
  • Quark masses m_c, m_b = m_c = 1.55 GeV, m_b = 4.88 GeV
    Taken from previous meson calculations [40]; not fit in this paper, but the absolute tetraquark masses depend linearly on them.
  • Strong coupling constants alpha_s = alpha_s(c cbar) = 0.314, alpha_s(b bbar) = 0.207, alpha_s(c bbar) = 0.265; qq values taken as half of q qbar
    Chosen as in meson calculations [40]; the treatment of qq vs q qbar pairs is an assumed model rule.
  • Confinement slope A_ij = A_ij = 0.18 GeV^2, halved for qq pairs
    Chosen as in meson calculations [40]; affects all mass values through the linear potential.
  • Confinement constant shift B = B = -0.8 GeV
    Ad hoc global energy shift, chosen equal for all states; affects absolute masses but not splittings.
  • Nonperturbative spin-spin parameter fV = fV = 0.9
    Introduced in Eq. (47) from quarkonium fits [44,45]; not derived in this paper, used for hyperfine splitting corrections.
assumptions (5)
  • domain assumption The tetraquark is described by a nonrelativistic Schroedinger equation with pairwise Coulomb plus linear confinement potential (Eqs. 5-6).
    The whole calculation rests on a quark model Hamiltonian, which is an assumed model of QCD, not derived. Section II.
  • domain assumption The tetraquark wave function is independent of hyperangles (K=0 hyperradial approximation), so the potential can be replaced by its average over the 8-dimensional sphere.
    Section III, Eqs. (14)-(18). This is the key truncation; the paper notes a 0.03 GeV difference with the variational method possibly due to angle dependence.
  • domain assumption For identical quark pairs, the color wave function is antisymmetric, and the confinement and Coulomb couplings for quark-quark pairs are half those of quark-antiquark pairs.
    Stated in Section II after Eq. (6); taken from [40].
  • domain assumption The spin-spin and relativistic corrections can be treated in first-order perturbation theory using the hyperradial wave function.
    Section IV and V; the paper computes matrix elements of delta-functions and p^4 operators with the approximate wave function, without estimating the error from the approximation except a global 0.1 GeV estimate.
  • domain assumption The nonperturbative spin-spin confinement potential (Eq. 47) with fV=0.9 contributes as given.
    Taken from quarkonium literature [44,45]; its transfer to tetraquarks is assumed.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Heavy tetraquarks in the hyperspherical approach." pith.science (2026). https://pith.science/paper/C5O6FZ2O

@misc{pith2026250910940,
  author       = {Pith},
  title        = {Pith review of: Heavy tetraquarks in the hyperspherical approach},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/C5O6FZ2O}},
  note         = {Machine review of arXiv:2509.10940}
}
read the original abstract

Within the quark model and hyperspherical method, the bound states of four heavy quarks and antiquarks (tetraquarks) are investigated. In hyperradial approximation, the Schroedinger equation is reduced to a one-dimensional equation after averaging over angles in hyperspace. This equation is solved numerically and analytically within the variational method. The hyperfine structure of the spectrum is calculated. To increase the accuracy of the calculation, corrections to the energy levels from the QCD generalization of the Breit Hamiltonian are taken into account.

Figures

Figures reproduced from arXiv: 2509.10940 by the authors.

Figure 1
Figure 1. FIG. 1: The Jacobi coordinates in a four-particle system. [PITH_FULL_IMAGE:figures/full_fig_p003_1.png] view at source ↗
Figure 2
Figure 2. FIG. 2: Binding energy as a function of two variational param [PITH_FULL_IMAGE:figures/full_fig_p008_2.png] view at source ↗
Figure 3
Figure 3. FIG. 3: Tetraquark wave function in the hyperradial approxi [PITH_FULL_IMAGE:figures/full_fig_p009_3.png] view at source ↗

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

47 extracted references · 11 canonical work pages

  1. [1]

    S. K. Choi, S. L. Olsen, K. Abe, T. Abe, et al. (Belle Collab oration), Observation of a narrow charmoniumlike state in exclusive B± → K ±π+π−J/Ψ decays, Phys. Rev. Lett. 91, 262001 (2003), https://doi.org/10.1103/PhysRevLett.91.262001

  2. [2]

    S. J. Brodsky, D. S. Hwang and R. F. Lebed, Dynamical Pictu re for the Forma- tion and Decay of the Exotic XYZ Mesons, Phys. Rev. Lett. 113, 112001, (2014); http://dx.doi.org/10.1103/PhysRevLett.113.112001

  3. [3]

    R. F. Lebed, R. E. Mitchell and E. S. Swanson, Heavy-quark QCD exotica, Prog. Part. Nucl. Phys., 93, 143, (2017); http://dx.doi.org/10.1016/j.ppnp.2016.1 1.003

  4. [4]

    Ablikim, M

    M. Ablikim, M. N. Achasov, P. Adlarson, S. Ahmed, M. Albre cht, R. Aliberti, A. Amoroso, Q. An, Anita et al. (BESIII Collaboration), Observation of a Near-Threshold Structure in the K + Recoil-Mass Spectra in e+e− → K +D− s D∗0 + D∗− s D0; Phys. Rev. Lett. 126, 102001 (2021); https://doi.org/10.1103/PhysRevLett.126.102001 16

  5. [5]

    First of all, these are radiative corrections of order O(αs) and relativistic corrections of higher order, which can be about 30 percent of those that are sta ted. Taking into account therefore the magnitude of individual effects ∼ 0.3 ÷ 0.5 GeV for the tetraquark ( cc¯c¯c) in this work, one can estimate the possible magnitude of theoretical c alculation e...

  6. [6]

    Aaij et al

    R. Aaij et al. [the LHCb Collaboration], Observation of s tructure in the J/Ψ -pair mass spectrum, Sci. Bull., 65, 1983, (2020); https://doi.org/10.1016/j.scib.2020.08 .032

  7. [7]

    H.-X. Chen, W. Chen, X. Liu, Y.-R. Liu and Sh.-L. Zhu, An up dated review of the new hadron states, Rep. Prog. Phys. 86, 026201 (2023), https://doi.org/10.1088/1361-6633/aca 3b6

  8. [8]

    Hayrapetyan et al

    A. Hayrapetyan et al. [the CMS Collaboration], New Struc tures in the J/ΨJ/Ψ Mass Spec- trum in Proton-Proton Collisions at √s = 13 TeV, Phys. Rev. Lett., 132, 111901, (2024); https://doi.org/10.1103/PhysRevLett.132.111901

Show all 47 references
  1. [9]

    Aad et al

    G. Aad et al. [the ATLAS Collaboration], Observation of a n Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector, Phys. R ev. Lett., 131, 151902, (2023); https://doi.org/10.1103/PhysRevLett.131.151902

  2. [10]

    R. N. Faustov, V. O. Galkin and E. M. Savchenko, Heavy tet raquarks in the relativistic quark model, Universe 7, 94 (2021), https://doi.org/10.3390/universe7040094

  3. [11]

    The CMS Collaboration, Observation of a family of all-ch arm tetraquark candidates at the LHC, CMS PAS BPH-24-003; https://cds.cern.ch/record/292 9472/files/BPH-24-003-pas.pdf

  4. [12]

    R. I. Jibuti and N. B. Krupennikova, The Method of Hypers pherical Functions in Quantum Mechanics of Several Bodies, Metsniereba, Tbilisi, 1984, ( In Russion)

  5. [13]

    R. N. Faustov, V. O. Galkin and E. M. Savchenko, Masses of the QQ ¯Q ¯Q tetraquarks in the relativistic diquark-antidiquark picture, Phys. Re v. D 102, 114030 (2020), https://doi:10.1103/PhysRevD.102.114030

  6. [14]

    A. M. Badalian and Yu. A. Simonov, The three body problem . Equation for the partial waves, Sov. J. Nucl. Phys. 3, 755 (1966)

  7. [15]

    T. K. Das, Hyperspherical Harmonics Expansion Techniq ues. Application to Problems in Physics, Springer, New Delhi, 2016

  8. [16]

    I. M. Narodetskii and M. A. Trusov, Ground state baryons in nonperturbative quark dynamics, Phys. Atom. Nucl. 67, 762 (2004)

  9. [17]

    B. O. Kerbikov and Yu. A. Simonov, Baryon magnetic momen ts in the QCD string approach, Phys. Rev. D 62, 093016 (2000)

  10. [18]

    A. P. Martynenko, Ground-state triply and doubly heavy baryons in a relativistic three-quark model, Phys. Lett. B 663, 317 (2008). 17

  11. [19]

    I. M. Narodetskii and M. A. Trusov, The Heavy baryons in t he nonperturbative string ap- proach, Phys. Atom. Nucl. 65, 917 (2002)

  12. [20]

    A. V. Nefediev, X(6200) as a compact tetraquark in the QC D string model, Eur. Phys. J. C (2021) 81:692; https://doi.org/10.1140/epjc/s10052-02 1-09511-z

  13. [21]

    I. M. Narodetskii, Yu. A. Simonov, M. A. Trusov, and A. I. Veselov, Pentaquark spectrum in string dynamics, Phys. Lett. B 578, 318 (2004)

  14. [22]

    This work extends the study of heavy tetraquarks, which we carr ied out within the vari- ational method [23]

    the hyperspherical harmonics method was used to study vect or P-wave tetraquarks. This work extends the study of heavy tetraquarks, which we carr ied out within the vari- ational method [23]. We calculate the energy levels of specific hadron ic states - tetraquarks (cc¯c¯c), (b...

  15. [23]

    Barnea, J

    N. Barnea, J. Vijande, and A. Valcarce, Four-quark spec troscopy within the hyperspherical formalism, Phys. Rev. D 73, 054004 (2006); http://dx.doi.org/10.1103/PhysRevD.73 .054004

  16. [24]

    A. M. Badalyan, B. L. Ioffe and A. V. Smilga, Four-quark sta tes in heavy quark systems, Nucl. Phys. B 281, 85 (1987); https://doi.org/10.1016/0550-3213(87)9024 8-3

  17. [25]

    A. V. Eskin, A. P. Martynenko and F. A. Martynenko, Mass s pectrum of heavy tetraquarks in variational approach, arXiv:2505.05993 [hep-ph]; https: //doi.org/10.48550/arXiv.2505.05993

  18. [26]

    Ader, J.-M

    J.-P. Ader, J.-M. Richard and P. Taxi1, Do narrow heavy m ultiquark states exist?, Phys. Rev. D 25, 2370 (1982); https://doi.org/10.1103/PhysRevD.25.237 0

  19. [27]

    H. X. Chen, W. Chen, X. Liu, and S. L. Zhu, The hidden-char m pentaquark and tetraquark states, Phys. Rep. 639, 1-121 (2016), https://doi.org/10.1016/j.physrep.2016 .05.004

  20. [28]

    S. L. Olsen, T. Skwarnicki and D. Zieminska, Nonstandar d heavy mesons and baryons: experimental evidence, Rev. Mod. Phys. 90, 015003 (2018), https://doi.org/10.1103/RevModPhys.90.015003

  21. [29]

    S. Pal, B. Chakrabarti and A. Bhattacharya, A theoretic al investigation on the spectroscopy and structure of the exotic tetraquark states, Nuclear Phys ics A 1029, 122559 (2023), https://doi.org/10.1016/j.nuclphysa.2022.122559

  22. [30]

    A. V. Berezhnoy, A. V. Luchinsky and A. A. Novoselov, Tet raquarks Composed of 4 Heavy Quarks, Phys. Rev. D 86, 034004 (2012); http://dx.doi.org/10.1103/PhysRevD.86 .034004

  23. [31]

    V. R. Debastiani and F. S. Navarra, A non-relativistic m odel for the [ cc][¯c¯c] tetraquark, Chinese Physics C 43, 1, 013105 (2019); https://iopscience.iop.org/article/ 10.1088/1674- 1137/43/1/013105/pdf

  24. [32]

    Wu, Y.-R

    J. Wu, Y.-R. Liu, K. Chen, X. Liu, and Sh.-L. Zhu, Heavy-fl avored tetraquark states with the QQ ¯Q ¯Q configuration, Phys. Rev. D 97, 094015 (2018); https://doi.org/10.1103/PhysRevD.97.094015

  25. [33]

    R. J. Lloyd and J. P. Vary, All-charm tetraquarks, Phys. Rev. D 70, 014009 (2004); https://doi.org/10.1103/PhysRevD.70.014009

  26. [34]

    M. A. Bedolla, J. Ferretti, C. D. Roberts and E. Santopin to, Spectrum of fully- 18 heavy tetraquarks from a diquark+antidiquark perspective , EPJ C, 80, 1004, (2020); https://doi.org/10.1140/epjc/s10052-020-08579-3

  27. [35]

    G. L. Yu, Z. Y. Li, Z. G. Wang, L. Jie, and Y. Meng, The S- and P-wave fully charmed tetraquark states and their radial excitations, Eu r. Phys. J. C (2023) 83:416; https://doi.org/10.1140/epjc/s10052-023-11445-7

  28. [36]

    D. M. Brink and Fl. Stancu, Tetraquarks with heavy flavor s, Phys. Rev. D 57, 6778 (1998)

  29. [37]

    Buccella, H

    F. Buccella, H. Hogaasen, J.-M. Richard, and P. Sorba, T etraquarks with heavy flavors, Eur. Phys. J. C 49, 743 (2007); DOI 10.1140/epjc/s10052-006-0142-1

  30. [38]

    Maiani, F

    L. Maiani, F. Piccinini, A. D. Polosa, and V. Riquer, Z(4 430) and a new paradigm for spin interactions in tetraquarks, Phys. Rev. D 89, 114010 (2014); http://dx.doi.org/10.1103/PhysRevD.89.114010

  31. [39]

    Park and S

    W. Park and S. H. Lee, Color spin wavefunctions of heavy t etraquark states, Nucl. Phys. A 925, 161 (2014); http://dx.doi.org/10.1016/j.nuclphysa.20 14.02.008

  32. [40]

    M.-S. Wu, Y. Zhang, J.-Y. Zhang, K. Varga, and Z.-C. Yan, Muonium-muonium interactions: Binding and scattering, Phys. Rev. A 110, 042822 (2024)

  33. [41]

    Bubin, M

    S. Bubin, M. Stanke, D. Kedziera, and L. Adamowicz, Rela tivistic corrections to the ground- state energy of the positronium molecule, Phys. Rev. A 75, 062504 (2007)

  34. [42]

    Ebert, R.N

    D. Ebert, R.N. Faustov, V.O. Galkin, and A.P. Martynenk o, Properties of doubly heavy baryons in the relativistic quark model, Phys. Atom. Nucl. 68, 784 (2005)

  35. [43]

    Lucha and F

    W. Lucha and F. F. Sch¨ oberl, Solving the Schr¨ odinger equation for bound states with Math- ematica 3.0, Int. J. Mod. Phys. C 10, 607 (1999)

  36. [44]

    F. A. Martynenko, A. P. Martynenko and A. V. Eskin, Produ ction of heavy quark bound states in rare exclusive decays of Higgs boson, arXiv: 2505.04530 [hep-ph]; https://arxiv.org/abs/2505.04530v1

  37. [45]

    F. A. Martynenko, A. V. Eskin and A. P. Martynenko, Produ ction of heavy tetraquarks in rare exclusive decays of the Higgs boson, arX iv:2509.08964 [hep-ph]; https://arxiv.org/abs/2509.08964v1

  38. [46]

    S. N. Gupta, S. F. Radford and W. W. Repko, Quarkonium spe ctra and quantum chromody- namics, Phys. Rev. D 26, 3305 (1982)

  39. [47]

    S. F. Radford and W. W. Repko, Potential model calculati ons and predictions for heavy quarkonium, Phys. Rev. D 75, 074031 (2007)

Pith tools

Reviewed August 4, 2026 · model on record in the stance chip above.