Pith. sign in

REVIEW 3 major objections 4 minor 5 cited by

Searching for a Sterile Neutrino in Tau Decays at B-factories

T0 review · 3 major / 4 minor · reviewed 2026-08-14 · deepseek-v4-flash

Pith's one-line read A displaced-vertex search in B-factory tau samples can probe tau-mixed sterile neutrinos down to |VτN|² ≈ 10⁻⁵.

desk verdict A clever, honest proposal for a tau-mixing sterile neutrino search at B-factories; the sensitivity projections are rough but the method is novel and worth refereeing. read the letter →

arxiv 1908.09719 v1 pith:CY6SGBZL submitted 2019-08-26 hep-ph

classification hep-ph PACS 14.60.Pq12.60.Jv14.80.Cp
keywords neutrinomassesandmixingtaudecayssterilelong-livedparticledisplacedvertexB-factoryBelleII
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 proposes a new search for a sterile neutrino $N$ with mass below the tau mass, $m_N < m_\tau$, that mixes predominantly with the tau neutrino. The method uses the large $e^+e^- \to \tau^+\tau^-$ samples collected at B-factory experiments (electron-positron colliders that copiously produce tau pairs): $N$ is produced in a tau decay such as $\tau \to \pi N$, travels a macroscopic distance because its lifetime scales roughly as $m_N^{-5}$, and then decays to a neutrino plus an $e^+e^-$ or $\mu^+\mu^-$ pair. The displaced vertex suppresses most backgrounds, and kinematic constraints that close the decay chain up to a two-fold ambiguity allow the sterile neutrino mass to be reconstructed. The paper estimates 95% confidence-level reach on $|V_{\tau N}|^2$ that beats the current best limits, reaching about $10^{-5}$ for $m_N \approx 1$ GeV at Belle II.

What carries the argument

The load-bearing mechanism is the displaced-vertex decay of the long-lived sterile neutrino combined with a kinematic-closure fit. The lifetime grows as $\tau_N \propto m_N^{-5}$, so for sub-GeV masses the $N$ flies tens of centimeters before decaying; the acceptance is defined by a decay-volume cut (10--80 cm in radius, $-40$ to $120$ cm in $z$) that rejects prompt tracks and most $K_S$ and material-interaction backgrounds. The fit uses 12 constraints — four-momentum conservation in the $\tau$ and $N$ decays, the known $\tau$ mass, the massless final neutrino, and the measured direction of flight of $N$ — to solve for the 12 unknown momentum components, leaving a two-fold ambiguity that yields two candidate masses $m_1,m_2$ and two candidate $\tau$ energies $E_1,E_2$. For signal, one solution peaks at the true $m_N$ and $E_\tau = \sqrt{s}/2$; for the dominant $K_L$ background the distributions are broad. The paper also uses the seesaw-motivated effective Lagrangian of Eq. (2), with the branching fractions of the production and decay modes taken from Refs. [63] and [68].

What would settle it

A full detector simulation of $e^+e^- \to \tau^+\tau^-$ events containing $\tau \to \pi K_L \nu$, $K_L \to \pi \mu \nu$ in Belle II, with the proposed four-track, displaced-dilepton-vertex, and $m_1/m_2$/$E_1/E_2$ selection applied, would settle the projection: if the background yield exceeds about 17 events per ab$^{-1}$ or the displaced-track signal efficiency falls below roughly 10%, the claimed background-free sensitivity and the $\sim 10^{-5}$ limit would not survive.

Watch

Extended reading notes

Core claim

The paper's central claim is that a sterile neutrino $N$ with $m_N < m_\tau = 1.777$ GeV and mixing $|V_{\tau N}| \gg |V_{eN}|, |V_{\mu N}|$ can be probed at B-factories through the decay chain $e^+e^- \to \tau^+\tau^-$, $\tau \to X_1 N$, $N \to \nu_\tau X_2$, where $X_1 = \pi^\pm$ or $\pi^\pm\pi^0$ and $X_2 = \ell^+\ell^-$. Because $N$ is long-lived, its decay vertex is displaced from the interaction point, and the paper shows that the unobserved neutrino still leaves enough constraints to determine the $N$ momentum and mass up to a two-fold ambiguity: four-momentum conservation in both decays, the known $\tau$ mass, the massless $\nu_\tau$, and the measured flight direction of $N$. These constraints make the $m_1$--$m_2$ and $E_1$--$E_2$ distributions narrow for signal and broad for background, so a simple cut retains 90% of signal while rejecting over 97% of the background. With the assumed detector efficiencies, the projected limits on $|V_{\tau N}|^2$ improve on the existing bound and reach about $10^{-5}$ at Belle II for $m_N$ near 1 GeV, with the full Belle II sample expected to be close to background-free.

Load-bearing premise

The projected sensitivity rests on hand-assigned detector efficiencies and background estimates — especially the 25% track-reconstruction efficiency for displaced tracks, the 90% vertex-rejection efficiency, and the $7.5 \times 10^{-5}$ acceptance-efficiency product for the $K_L$ background — rather than on a full detector simulation, and the paper itself notes the pion misidentification rate could vary by a factor of two.

Editorial extensions

If this is right

  • BaBar and Belle data already in hand could improve on the current limit for $m_N < m_\tau$ without any new accelerator running.
  • With the full Belle II sample the search becomes nearly background-free, and the projected limit around $10^{-5}$ at $m_N \approx 1$ GeV would reach a corner of parameter space that lepton-flavor-based searches and dedicated long-lived-particle experiments are not designed to cover.
  • If a signal appears, the $(m_1,m_2)$ and $(E_1,E_2)$ distributions give a direct measurement of the sterile neutrino mass and confirm that it originated in a $\tau$ decay.
  • Including the modes $X_1 = \ell\nu$ and $X_2 = \pi^+\pi^-$ would roughly double the exploited branching fraction and further improve sensitivity, provided full simulation validates the assumed efficiencies.

Reading between the lines

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

  • Editorial inference: the same kinematic closure could in principle reconstruct $m_N$ from the leptonic tau mode $\tau \to \ell\nu N$, but the extra missing neutrino would make the fit underdetermined; the hadronic $X_1$ choice is what makes the mass extraction practical.
  • Editorial inference: because the $N$ lifetime scales as $m_N^{-5}$, sensitivity below $m_N \sim 0.3$ GeV is limited mainly by the decay volume — most decays would happen beyond the 80 cm cylinder — so a detector with a larger instrumented radius could extend the search to lower masses.
  • Editorial inference: the displaced $e^+e^-$ or $\mu^+\mu^-$ signature is flavor-blind, so the same selection could be reinterpreted to constrain a sterile neutrino with a subdominant $V_{\mu N}$ or $V_{eN}$ component, providing a cross-check on the tau-mixing interpretation.
  • Editorial inference: if the predicted background of roughly six events in the entire Belle II sample is realized, a small cluster of events in the same-mass window would already be a strong new-physics signal, making early Belle II data scientifically interesting.
Share X Bluesky LinkedIn Reddit HN

Signed reviews

No signed human review yet.

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 proposes a search for a sterile neutrino N with mass below the tau mass that mixes predominantly with the tau neutrino, using tau-pair events at B-factories (BaBar, Belle, Belle II). The proposed signature is tau -> X1 N followed by N -> nu_tau l+l- with a displaced vertex, exploiting the long lifetime of N. The authors use EvtGen-generated events to estimate acceptance and kinematic variables, and they estimate detector-level efficiencies by hand. They find that a bin-by-bin cut on the two mass solutions (m1, m2) and two CM-energy solutions (E1, E2) retains 90% of signal and rejects over 97% of the KL background, leading to a nearly background-free Belle II analysis. Expected 95% CL limits on |V_tauN|^2 are shown in Fig. 3, surpassing the DELPHI bound by up to several orders of magnitude at Belle II.

Significance. The method addresses a genuine experimental gap: for mN < m_tau, the best existing limit on |V_tauN|^2 comes from the lepton-flavor-agnostic DELPHI search, and a dedicated tau-decay search at B-factories could improve it substantially. The paper is conceptually sound and transparent about its simplifications; it clearly labels the analysis as an estimate and identifies the need for full simulation of leptonic tau modes. If the projected sensitivities are validated by a detector-level study, the paper would provide a strong motivation for a concrete experimental search. However, the central quantitative claim depends on several hand-assigned efficiencies and generator-level background rejection rates, so the numerical curves in Fig. 3 are not yet robust.

major comments (3)
  1. [Further background suppression paragraph, p. 3-4] The kinematic constraints use the unit vector from the X1 production point to the X2 decay vertex as the direction of p_N. For the X1 = pi mode, the tau decay vertex is not directly reconstructable from the single charged pion track; if the beam spot is used as an approximation, the tau flight length (hundreds of microns to ~1 mm) introduces an angular uncertainty on p_N of order 1e-2 rad for N decays at r ~ 10 cm. This smearing is not included in the EvtGen-level distributions of Fig. 2, as the paper itself notes that detector resolution is not simulated. The claimed 90% signal retention and 97% background rejection, and hence the estimated 6 background events in the full Belle II sample, therefore rest on an unvalidated idealization. Please provide a quantitative estimate of this smearing or a detector-level simulation, and show how the retained signal and rejected background change.
  2. [KL background estimate, p. 4] The background yield in the full Belle II sample is estimated as 850 events before the mass-energy cuts, based on a pion mis-identification efficiency of 0.5% that the authors acknowledge can vary by a factor of 2, and on a 1.4% acceptance obtained from EvtGen. The post-cut background of 6 events follows from applying the 97% rejection derived from generator-level distributions. If the mis-ID rate or the acceptance is a factor of 2 higher, the pre-cut background doubles; if the rejection is 95% instead of 97%, the post-cut background becomes roughly 40 events at the nominal pre-cut level. These variations would shift the 95% CL limits in Fig. 3 by a nontrivial factor and could invalidate the 'background-free' statement for Belle II. Please quantify the sensitivity under these plausible variations and show the resulting uncertainty band in Fig. 3.
  3. [Efficiency accounting after cuts, p. 4] The text states that a bin-by-bin cut 'retains 90% of the signal events' and then, after concluding that a sophisticated analysis 'can come close to being background-free,' the authors 'assume an additional efficiency loss of 75% to account for these cuts.' It is unclear whether this means a retained fraction of 75% (0.9 x 0.75 = 0.675) or a loss of 75% (0.9 x 0.25 = 0.225). The wording 'efficiency loss' suggests the latter, but that is hard to reconcile with the 90% retention claim. The effective signal efficiency that goes into Eq. (3) for the limits in Fig. 3 should be stated explicitly, and the relation between the 90% retention, the 75% factor, and the previously estimated epsilon = 10% should be clarified.
minor comments (4)
  1. [Paragraph after Fig. 2] The phrase 'by initial-state radiaion (ISR)' contains a typo; it should read 'initial-state radiation.'
  2. [Abstract] The phrase 'a ντ-mixing' is grammatically awkward; consider 'mixing with the τ neutrino' for clarity.
  3. [Fig. 3 caption and final sensitivity estimate] The 'Belle II(+other modes)' curve includes X1 = l nu and X2 = pi+ pi- modes assuming the same signal efficiency as X1 = pi, while the text states that the leptonic X1 mode requires full detector simulation and is not studied in detail. Please label this curve as an idealized extrapolation in the caption and in the summary, so that it is not read as a validated sensitivity projection.
  4. [Section 'Our aim here is to estimate...', Eq. (3)] The acceptance a is defined as essentially the probability for N to decay inside the detector, but the numerical acceptance values used for the Fig. 3 curves are not tabulated. A table listing a and epsilon for each mass point and experiment would improve reproducibility.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: the projected sensitivity follows from an explicit event-count formula with externally sourced decay widths, Monte Carlo acceptance, and stated efficiency assumptions; no fitted quantity is relabeled as a prediction.

full rationale

The derivation chain is self-contained. The signal yield is computed as N = N_tau_tau x B(tau -> X1 N) x B(N -> nu_tau X2) x a x epsilon (Eq. 3), with B(tau -> X1 N) taken from the published parameter-free calculation in Ref. [63] and B(N -> nu_tau X2) from the external Ref. [68]. Two co-authors also appear on Ref. [63], but that citation supplies an input branching fraction, not the predicted limit, and the central sensitivity curves are not a restatement of that formula. The acceptance a is obtained from EvtGen signal simulation, and epsilon is an explicitly stated detector-efficiency assumption (25% track finding, 60% particle ID, 90% vertex rejection, 75% post-cut retention); none of these is fitted to the projected limits. The kinematic mass reconstruction is derived from the assumed decay chain's 12 unknowns and 12 constraints and is tested on independently generated signal and KL-background events; the signal m1/m2 and E1/E2 peaks are consequences of those constraints, not inputs disguised as predictions. The text's own caveats, such as 'additional smearing is expected due to detector resolution, not included in this simulation' and 'Conducting these fits is beyond the scope of this study,' are stated limitations of the estimate rather than circular reductions. The Belle II sensitivity projection therefore scales standard physics inputs and does not reduce by construction to any fitted parameter or self-citation chain.

Assumptions & free parameters 4 free parameters · 5 assumptions · 0 invented entities

No new particles or forces are introduced by this paper; the sterile neutrino N is the standard seesaw right-handed state. The central projection instead depends on several hand-assigned Monte Carlo efficiencies, on theoretical branching fractions from prior literature (including Ref. [63] by some of the same authors), and on the assumed dominance of V_tau_N. The paper contributes a search strategy and a sensitivity estimate rather than a parameter-free derivation.

free parameters (4)
  • Signal efficiency epsilon for X1 = pi mode = about 10% (about 5% for X1 = pi pi0)
    Hand-assigned from assumed track reconstruction (25%), particle ID (60%), and vertex rejection (90%) efficiencies. This value directly scales the number of signal events and hence the sensitivity curves.
  • KL background acceptance-efficiency product a x epsilon = about 7.5 x 10^-5, about 850 events in the full Belle II sample
    Estimated from EvtGen acceptance of 1.4% and pion mis-ID probability of 0.5%. The paper notes this can change by a factor of 2, yet the projected background count is treated as a single number.
  • Additional signal efficiency loss from mass-energy cuts = 75% signal retained
    Chosen by hand to account for simple bin-by-bin cuts estimated from generator-level distributions. This assumption affects the final Belle II limit in Fig. 3.
  • Acceptance volume boundary = 10 < r < 80 cm, -40 < z < 120 cm
    Defines where the N decay must occur to be accepted. The choice affects the acceptance for long-lived N and is not derived from a detailed detector model.
assumptions (5)
  • domain assumption Seesaw extension with right-handed Majorana neutrinos is a valid framework; SM neutrinos are light fields with small admixtures of heavier sterile states.
    Introduced in the 'Theoretical framework' section via Eq. (1). This is the standard model extension assumed throughout.
  • ad hoc to paper The sterile neutrino N mixes predominantly with the tau neutrino, so only the V_tau_N couplings in Eq. (2) are relevant.
    The paper deliberately restricts to |V_tau_N| >> |V_e_N|, |V_mu_N| to target the experimentally weakest mixing. This is a scenario choice, not a consequence of any proven model.
  • domain assumption For mN < m_tau, the charged-current decay N to tau W* is kinematically forbidden, and N decays mainly through the neutral-current channel N to nu_tau X2.
    States the decay chain in the text and Fig. 1. The neutral-current dominance follows from the model assumptions, but the branching fractions are taken from external Ref. [68].
  • standard math The production branching fractions B(tau to pi N) and B(tau to pi pi N) from Ref. [63] are correct.
    The paper writes that these can be obtained from Eqs. (3) and (5) of Ref. [63] without re-deriving them. The sensitivity calculation depends on these values.
  • standard math The kinematic system with 12 unknowns and 12 constraints is solvable and yields the N mass up to a twofold ambiguity.
    Described in the paragraph beginning 'The decay chain cannot be fully reconstructed'. The existence and uniqueness properties of the solution are asserted, not proven in the text.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Searching for a Sterile Neutrino in Tau Decays at B-factories." pith.science (2026). https://pith.science/paper/CY6SGBZL

@misc{pith2026190809719,
  author       = {Pith},
  title        = {Pith review of: Searching for a Sterile Neutrino in Tau Decays at B-factories},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/CY6SGBZL}},
  note         = {Machine review of arXiv:1908.09719}
}
abstract

The phenomenon of neutrino flavor oscillations motivates searches for sterile neutrinos in a broad range of masses and mixing-parameter values. A sterile neutrino $N$ that mixes predominantly with the $\tau$ neutrino is particularly challenging experimentally. To address this challenge, we propose a new method to search for a $\nu_\tau$-mixing with $N$ lighter than the $\tau$ lepton. The method uses the large $e^+e^-\to\tau^+\tau^-$ samples collected at $B$-factory experiments to produce the $N$ in $\tau$-lepton decays. We exploit the long lifetime of a sterile neutrino in this mass range to suppress background and apply kinematic and vertexing constraints that enable measuring the sterile neutrino mass. Estimates for the sensitivities of the BaBar, Belle, and Belle~II experiments are calculated and presented.

Figures

Figures reproduced from arXiv: 1908.09719 by the authors.

Figure 1
Figure 1. FIG. 1. The proposed decay chain, [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. FIG. 2. Distributions of the [PITH_FULL_IMAGE:figures/full_fig_p004_2.png] view at source ↗

Discussion (0). Continue with ORCID to comment.

Forward citations

Cited by 5 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

  1. Same-sign dimuon probe of charged lepton flavor violation at electron-photon colliders

    hep-ph 2026-03 conditional novelty 6.0 of 10

    Electron–photon collisions are shown to probe axionlike-particle e–mu flavor-violating couplings via a same-sign dimuon signature, with projected sensitivity one to two orders below current bounds.

  2. Estimating the track-reconstruction efficiency in phenomenological proposals of long-lived-particle searches

    hep-ex 2025-01 conditional novelty 6.0 of 10

    TrackEff estimates Belle II track-reconstruction efficiency by geometrically counting drift-chamber hits, with default thresholds tuned to a Belle II tau-tau tracking efficiency measurement.

  3. A comprehensive study of ALPs from $B$-decays

    hep-ph 2024-12 conditional novelty 6.0 of 10

    The paper derives the complete two-loop flavor-changing coupling of axion-like particles to b and s quarks and uses it to set updated limits on f_a in KSVZ, DFSZ and Flaxion models.

  4. Long-lived sterile neutrinos from axionlike particles at the Super Tau-Charm Facility

    hep-ph 2026-05 unverdicted novelty 5.0 of 10

    STCF can reach |V_eN|^2 values one to two orders of magnitude below current bounds for heavy neutral leptons via displaced-vertex searches from ALP decays in D-meson production.

  5. Sensitivity of Lepton Number Violating Meson Decays in Different Experiments

    hep-ph 2019-08 conditional novelty 5.0 of 10

    For 0.14 to 6 GeV heavy neutrinos, accounting for the parent meson's velocity weakens projected LNV meson decay sensitivities by one to two orders of magnitude at NA62 and SHiP.

Reference graph

Works this paper leans on

72 extracted references · 25 canonical work pages · cited by 5 Pith papers

  1. [63]

    C. O. Dib, C. S. Kim, N. A. Neill and X. B. Yuan, Phys. Rev. D 97, no. 3, 035022 (2018) [arXiv:1801.03624 [hep- ph]]

  2. [18]

    C. O. Dib, M. Campos and C. S. Kim, JHEP 1502, 108 (2015) [arXiv:1403.8009 [hep-ph]]

  3. [1]

    Fukuda et al

    Y. Fukuda et al. [Super-Kamiokande Collaboration], Phys. Rev. Lett. 81, 1562 (1998) [hep-ex/9807003]

  4. [2]

    Q. R. Ahmad et al. [SNO Collaboration], Phys. Rev. Lett. 89, 011301 (2002) [nucl-ex/0204008]

  5. [3]

    Eguchi et al

    K. Eguchi et al. [KamLAND Collaboration], Phys. Rev. Lett. 90, 021802 (2003) [hep-ex/0212021]

  6. [4]

    Tanabashi et al

    M. Tanabashi et al. [Particle Data Group], Phys. Rev. D 98, no. 3, 030001 (2018)

  7. [5]
  8. [6]

    Aad et al

    G. Aad et al. [ATLAS Collaboration], JHEP 1507, 162 (2015) [arXiv:1506.06020 [hep-ex]]

Show all 72 references
  1. [7]

    A. M. Sirunyan et al. [CMS Collaboration], Phys. Rev. Lett. 120, no. 22, 221801 (2018) [arXiv:1802.02965 [hep- ex]]

  2. [8]

    Aad et al

    G. Aad et al. [ATLAS Collaboration], arXiv:1905.09787 [hep-ex]

  3. [9]

    J. M. Zhang and G. L. Wang, Eur. Phys. J. C 71, 1715 (2011) [arXiv:1003.5570 [hep-ph]]

  4. [10]

    H. Yuan, T. Wang, G. L. Wang, W. L. Ju and J. M. Zhang, JHEP 1308, 066 (2013) [arXiv:1304.3810 [hep-ph]]

  5. [11]

    J. C. Helo, S. Kovalenko and I. Schmidt, Nucl. Phys. B 853, 80 (2011) [arXiv:1005.1607 [hep-ph]]

  6. [12]

    C. Dib, V. Gribanov, S. Kovalenko and I. Schmidt, Phys. Lett. B 493, 82 (2000) [hep-ph/0006277]

  7. [13]

    Cvetic, C

    G. Cvetic, C. Dib, S. K. Kang and C. S. Kim, Phys. Rev. D 82, 053010 (2010) [arXiv:1005.4282 [hep-ph]]

  8. [14]

    C. Dib, J. C. Helo, S. Kovalenko and I. Schmidt, Phys. Rev. D 84, 071301 (2011) [arXiv:1105.4664 [hep-ph]]

  9. [15]

    Cvetic, C

    G. Cvetic, C. Dib and C. S. Kim, JHEP 1206, 149 (2012) [arXiv:1203.0573 [hep-ph]]

  10. [16]

    Bonivento et al., arXiv:1310.1762 [hep-ex]

    W. Bonivento et al., arXiv:1310.1762 [hep-ex]

  11. [17]

    Cveti, C

    G. Cveti, C. S. Kim and J. Zamora-Sa, J. Phys. G 41, 075004 (2014) [arXiv:1311.7554 [hep-ph]]

  12. [19]

    J. P. Lees et al. [BaBar Collaboration], Phys. Rev. D 89, no. 1, 011102 (2014) [arXiv:1310.8238 [hep-ex]]

  13. [20]

    H. R. Dong, F. Feng and H. B. Li, Chin. Phys. C 39, no. 1, 013101 (2015) [arXiv:1305.3820 [hep-ph]]

  14. [21]

    Cveti, C

    G. Cveti, C. S. Kim and J. Zamora-Sa, Phys. Rev. D 89, no. 9, 093012 (2014) [arXiv:1403.2555 [hep-ph]]

  15. [22]

    Cvetic, C

    G. Cvetic, C. S. Kim, R. Kogerler and J. Zamora-Saa, Phys. Rev. D 92, 013015 (2015) [arXiv:1505.04749 [hep- ph]]

  16. [23]

    Moreno and J

    G. Moreno and J. Zamora-Saa, Phys. Rev. D 94, no. 9, 093005 (2016) [arXiv:1606.08820 [hep-ph]]

  17. [24]

    Gribanov, S

    V. Gribanov, S. Kovalenko and I. Schmidt, Nucl. Phys. B 607, 355 (2001) [hep-ph/0102155]

  18. [25]

    Lopez Castro and N

    G. Lopez Castro and N. Quintero, Phys. Rev. D 85, 076006 (2012) Erratum: [Phys. Rev. D 86, 079904 (2012)] [arXiv:1203.0537 [hep-ph]]

  19. [26]

    Zamora-Saa, JHEP 1705, 110 (2017) [arXiv:1612.07656 [hep-ph]]

    J. Zamora-Saa, JHEP 1705, 110 (2017) [arXiv:1612.07656 [hep-ph]]

  20. [27]

    J. C. Helo, S. Kovalenko and I. Schmidt, Phys. Rev. D 84, 053008 (2011) [arXiv:1105.3019 [hep-ph]]

  21. [28]

    C. Dib, J. C. Helo, M. Hirsch, S. Kovalenko and I. Schmidt, Phys. Rev. D 85, 011301 (2012) [arXiv:1110.5400 [hep-ph]]

  22. [29]

    Quintero, G

    N. Quintero, G. Lopez Castro and D. Delepine, Phys. Rev. D 84, 096011 (2011) Erratum: [Phys. Rev. D 86, 079905 (2012)] [arXiv:1108.6009 [hep-ph]]

  23. [30]

    J. C. Helo, M. Hirsch and S. Kovalenko, Phys. Rev. D89, 073005 (2014) Erratum: [Phys. Rev. D 93, no. 9, 099902 (2016)] [arXiv:1312.2900 [hep-ph]]

  24. [31]

    C. O. Dib and C. S. Kim, Phys. Rev. D 92, no. 9, 093009 (2015) [arXiv:1509.05981 [hep-ph]]

  25. [32]

    C. O. Dib, C. S. Kim, K. Wang and J. Zhang, Phys. Rev. D 94, no. 1, 013005 (2016) [arXiv:1605.01123 [hep-ph]]

  26. [33]

    Cveti, A

    G. Cveti, A. Das and J. Zamora-Sa, J. Phys. G 46, 075002 (2019) [arXiv:1805.00070 [hep-ph]]

  27. [34]

    Antusch, E

    S. Antusch, E. Cazzato and O. Fischer, Phys. Lett. B 774, 114 (2017) [arXiv:1706.05990 [hep-ph]]

  28. [35]

    Cottin, J

    G. Cottin, J. C. Helo and M. Hirsch, Phys. Rev. D 98, no. 3, 035012 (2018) [arXiv:1806.05191 [hep-ph]]

  29. [36]

    Abada, N

    A. Abada, N. Bernal, M. Losada and X. Marcano, JHEP 1901, 093 (2019) [arXiv:1807.10024 [hep-ph]]

  30. [37]

    Abreu et al

    P. Abreu et al. [DELPHI Collaboration], Z. Phys. C 74, 57 (1997) Erratum: [Z. Phys. C 75, 580 (1997)]

  31. [38]

    Aubert et al

    B. Aubert et al. [BaBar Collaboration], Nucl. Instrum. Meth. A 479, 1 (2002) [hep-ex/0105044]

  32. [39]

    Abashian et al

    A. Abashian et al. , Nucl. Instrum. Meth. A 479, 117 (2002)

  33. [40]

    Abe et al

    T. Abe et al. [Belle-II Collaboration], arXiv:1011.0352 [physics.ins-det]

  34. [41]

    Dib and C

    C. Dib and C. S. Kim, Phys. Rev. D 89, no. 7, 077301 (2014) [arXiv:1403.1985 [hep-ph]]

  35. [42]

    R. E. Shrock, Phys. Rev. Lett. 40, 1688 (1978)

  36. [43]

    L. Lee, C. Ohm, A. Soffer and T. T. Yu, Prog. Part. Nucl. Phys. 106, 210 (2019) [arXiv:1810.12602 [hep-ph]]

  37. [44]

    Alimena et al., arXiv:1903.04497 [hep-ex]

    J. Alimena et al., arXiv:1903.04497 [hep-ex]

  38. [45]

    Liventsev et al

    D. Liventsev et al. [Belle Collaboration], Phys. Rev. D 87, no. 7, 071102 (2013) Erratum: [Phys. Rev. D 95, no. 6 9, 099903 (2017)] [arXiv:1301.1105 [hep-ex]]

  39. [46]

    J. P. Lees et al. [BaBar Collaboration], Phys. Rev. Lett. 114, no. 17, 171801 (2015) [arXiv:1502.02580 [hep-ex]]

  40. [47]

    Kobach and S

    A. Kobach and S. Dobbs, Phys. Rev. D 91, no. 5, 053006 (2015) [arXiv:1412.4785 [hep-ph]]

  41. [48]

    Alekhin et al

    S. Alekhin et al. , Rept. Prog. Phys. 79, no. 12, 124201 (2016) [arXiv:1504.04855 [hep-ph]]

  42. [49]

    V. V. Gligorov, S. Knapen, M. Papucci and D. J. Robin- son, Phys. Rev. D 97, no. 1, 015023 (2018) [arXiv:1708.09395 [hep-ph]]

  43. [50]

    Kling and S

    F. Kling and S. Trojanowski, Phys. Rev. D 97, no. 9, 095016 (2018) [arXiv:1801.08947 [hep-ph]]

  44. [51]

    J. C. Helo, M. Hirsch and Z. S. Wang, JHEP 1807, 056 (2018) [arXiv:1803.02212 [hep-ph]]

  45. [52]

    Curtin et al., arXiv:1806.07396 [hep-ph]

    D. Curtin et al., arXiv:1806.07396 [hep-ph]

  46. [53]

    Dercks, H

    D. Dercks, H. K. Dreiner, M. Hirsch and Z. S. Wang, Phys. Rev. D 99, no. 5, 055020 (2019) [arXiv:1811.01995 [hep-ph]]

  47. [54]

    Ahdida et al

    C. Ahdida et al. [SHiP Collaboration], JHEP 1904, 077 (2019) [arXiv:1811.00930 [hep-ph]]

  48. [55]

    V. V. Gligorov, S. Knapen, B. Nachman, M. Papucci and D. J. Robinson, Phys. Rev. D 99, no. 1, 015023 (2019) [arXiv:1810.03636 [hep-ph]]

  49. [56]

    Minkowski, Phys

    P. Minkowski, Phys. Lett. 67B, 421 (1977)

  50. [57]

    Yanagida, Conf

    T. Yanagida, Conf. Proc. C 7902131, 95 (1979)

  51. [58]

    Gell-Mann, P

    M. Gell-Mann, P. Ramond and R. Slansky, Conf. Proc. C 790927, 315 (1979) [arXiv:1306.4669 [hep-th]]

  52. [59]

    R. N. Mohapatra and G. Senjanovic, Phys. Rev. D 23, 165 (1981)

  53. [60]

    S. L. Glashow, NATO Sci. Ser. B 61, 687 (1980)

  54. [61]

    Schechter and J

    J. Schechter and J. W. F. Valle, Phys. Rev. D 22, 2227 (1980)

  55. [62]

    R. N. Mohapatra and J. W. F. Valle, Phys. Rev. D 34, 1642 (1986)

  56. [64]

    D. J. Lange, Nucl. Instrum. Meth. A 462, 152 (2001)

  57. [65]

    Brandenburg et al

    G. Brandenburg et al. [CLEO Collaboration], Phys. Rev. D 61, 072002 (2000) [hep-ex/9907057]

  58. [66]

    Allmendinger et al., Nucl

    T. Allmendinger et al., Nucl. Instrum. Meth. A 704, 44 (2013) [arXiv:1207.2849 [hep-ex]]

  59. [67]

    Aubert et al

    B. Aubert et al. [BaBar Collaboration], Nucl. Instrum. Meth. A 729, 615 (2013) [arXiv:1305.3560 [physics.ins- det]]

  60. [68]

    Bondarenko, A

    K. Bondarenko, A. Boyarsky, D. Gorbunov and O. Ruchayskiy, JHEP 1811, 032 (2018) [arXiv:1805.08567 [hep-ph]]

  61. [69]

    Jadach, B

    S. Jadach, B. F. L. Ward and Z. Was, Comput. Phys. Commun. 130, 260 (2000) [hep-ph/9912214]

  62. [70]

    Gross and O

    E. Gross and O. Vitells, Eur. Phys. J. C 70, 525 (2010) [arXiv:1005.1891 [physics.data-an]]

  63. [71]

    Bergsma et al

    F. Bergsma et al. [CHARM Collaboration], Phys. Lett. 166B, 473 (1986)

  64. [72]

    J. P. Lees et al. [BaBar Collaboration], Phys. Rev. D 86, 032013 (2012) [arXiv:1205.2228 [hep-ex]]

Pith tools

Reviewed August 14, 2026 · model on record in the stance chip above.