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Modeling blazar broadband emission with convolutional neural networks -- III. proton synchrotron and hybrid models

T0 review · 3 major / 5 minor · reviewed 2026-08-06 · deepseek-v4-flash

Pith's one-line read A convolutional neural network can reproduce proton-synchrotron and hybrid blazar emission fast enough for Bayesian multimessenger fits.

desk verdict Genuine extension of the CNN surrogate to hadronic scenarios, but the accuracy claim rests on internal validation alone and the posteriors are never checked against direct SOPRANO runs. read the letter →

arxiv 2506.23885 v1 pith:Q32EYOYY submitted 2025-06-30 astro-ph.HE astro-ph.GA

classification astro-ph.HEastro-ph.GA
keywords blazarshadronicmodelsprotonsynchrotronhybridlepto-hadronicconvolutionalneuralnetworksmultimessengerastronomyneutrinoemissionspectralenergydistributions
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

This paper tries to establish that hadronic and hybrid models of blazar jets, which normally require minutes of computation per spectrum, can be replaced by a fast convolutional neural network without losing the essential physics. The network is trained on seven million spectra from the SOPRANO kinetic code, covering proton-synchrotron and hybrid lepto-hadronic scenarios, and it reproduces both the electromagnetic and the neutrino output. If the surrogate is as accurate as claimed, multimessenger fitting that combines radio-to-gamma-ray data with IceCube neutrino constraints becomes practical enough for full statistical exploration of the parameter space. The paper demonstrates the approach on TXS 0506+059 and PKS 0735+178, two blazars associated with IceCube neutrinos, showing that the preferred scenario can shift depending on how the neutrino information is encoded.

What carries the argument

The load-bearing object is a composite convolutional neural network trained on spectral outputs of SOPRANO, an implicit kinetic code that evolves the coupled Fokker–Planck equations for electrons, protons, photons, neutrons, and secondary particles (Equations 3 and 4). The network maps ten physical parameters — Doppler factor, blob radius, magnetic field, electron and proton injection indices, minimum and maximum electron Lorentz factors, maximum proton Lorentz factor, and electron and proton luminosities — to electromagnetic and neutrino spectra. The photon parameter space is split into four overlapping luminosity regions, each with its own network whose outputs are averaged in overlaps, and spectral derivatives are included in the training target to suppress oscillations; separate networks handle the neutrino spectra. This surrogate is what makes full posterior sampling of hadronic models computationally affordable.

What would settle it

Run SOPRANO at the best-fit parameter sets in Table 2 and at random parameter draws from the fitted posteriors, then compare the resulting electromagnetic and neutrino spectra with the CNN predictions; a mismatch larger than the quoted mean absolute error in the regions that drive the fits would show that the surrogate's posterior is biased.

Watch

Extended reading notes

Core claim

The central claim is that a convolutional neural network trained on $7\times10^6$ spectra generated by the SOPRANO code can act as a surrogate for the full time-dependent hadronic model, reproducing the broadband electromagnetic and neutrino spectra of both proton-synchrotron and hybrid lepto-hadronic scenarios. The authors report an average validation $R^2=0.66$ and mean absolute error $5.05\times10^{-3}$ across the four photon networks, with similar behaviour for the neutrino networks. Coupled to a Bayesian sampler, the surrogate recovers best-fit parameter sets for TXS 0506+059 and PKS 0735+178: a Gaussian likelihood on an assumed neutrino spectrum favours a hybrid model for TXS 0506+059, while a Poisson event-count likelihood favours a proton-synchrotron model for the same source, and the PKS 0735+178 posterior is bimodal between the two scenarios.

Load-bearing premise

The entire fitting exercise rests on the trained network being a faithful stand-in for the numerical model, even though it was only validated against spectra drawn from the same simulation database used for training.

Editorial extensions

If this is right

  • For TXS 0506+059, the preferred model depends on the neutrino likelihood: a Gaussian likelihood on an assumed neutrino spectrum favours a hybrid scenario, while a Poisson likelihood based on one IceCube event per year favours proton synchrotron.
  • For PKS 0735+178, the Poisson-likelihood fit favours a proton-synchrotron solution, but the posterior is bimodal with a secondary hybrid mode, so the current multimessenger data cannot cleanly distinguish the two scenarios.
  • Because the CNN is fast, full posterior sampling becomes feasible, allowing model selection between P-syn and hybrid scenarios to be driven by the data rather than fixed before the fit.
  • The trained network is released as an online fitting service, letting other researchers fit their own multimessenger SEDs without recomputing the seven-million-spectrum simulation database.
  • A stated next step is to include external photon fields, which would extend the surrogate to sources with accretion disks or broad-line regions.

Reading between the lines

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

  • The validation metrics are measured only on spectra drawn from the same simulation database used for training; the paper does not propagate surrogate error into the posterior, so a locally biased region of the CNN could masquerade as a preferred model, for instance in the PKS 0735+178 bimodality.
  • A direct test of reliability would be to run SOPRANO at the best-fit parameters and at random posterior draws and compare the predicted spectra; the reported $R^2$ alone does not guarantee uniform accuracy across the parameter space.
  • The Poisson-likelihood results assume one detected neutrino in a one-year IceCube exposure and use a specific effective area; altering those assumptions would shift the inferred proton luminosity and could change the hybrid-versus-P-syn balance.
  • Because the paper explicitly excludes external photon fields, the current surrogate is most directly applicable to BL Lac-type jets; adding external radiation could reduce the very high proton luminosity found for TXS 0506+059.
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Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

3 major / 5 minor

Summary. This paper extends the authors' prior CNN-based surrogate modeling program to hadronic and hybrid lepto-hadronic blazar emission models. A convolutional neural network is trained on 7e6 synthetic spectra generated with the SOPRANO kinetic code over a wide parameter space, augmented by focused sampling in proton-synchrotron and hybrid regions. The trained surrogate, comprising separate CNNs for photon and neutrino outputs, is coupled to MultiNest and applied to fit the multimessenger SEDs of TXS 0506+059 and PKS 0735+178 under two neutrino likelihood treatments: a Gaussian likelihood using assumed neutrino flux points and a Poisson likelihood based on one IceCube event in one year. The paper reports best-fit parameters for both sources, finds hybrid or proton-synchrotron solutions depending on the likelihood and source, and makes the trained model available through the MMDC web platform.

Significance. If the emulator's fidelity is confirmed at the fitted parameter values, this is a useful and timely contribution: it would make Bayesian fitting of computationally expensive hadronic blazar models practical and would provide the community with a public tool for multimessenger SED interpretation. The scale of the training database (7e6 SOPRANO spectra), the integration into MMDC, and the explicit treatment of neutrino likelihoods are concrete strengths. The central claim, however, is that the CNN 'effectively reproduces' SOPRANO's electromagnetic and neutrino outputs; the support offered for that claim is internal validation only, and the reported average R2=0.66 is modest. The significance of the astrophysical applications is therefore conditional on an additional validation step that is currently missing.

major comments (3)
  1. [§3.3] The validation metrics reported in §3.3 (average R2=0.66, MSE=2.25e-3, MAE=5.05e-3 across the four photon models) are not sufficient to support the claim of 'great accuracy' in the Figure 1 caption, and no region-resolved or spectral-band-specific metrics are provided. The statement 'Similar results hold for neutrinos' is given without any quantitative support, even though the neutrino output is the decisive input for the Gaussian-versus-Poisson comparison in §4.2. The authors should report per-region accuracy, worst-case residuals, and neutrino-specific metrics (e.g., R2 or MAE on the relevant energy range) before claiming that the surrogate reliably reproduces multimessenger spectra.
  2. [§4] All fits in Section 4, including the plotted best-fit SEDs, gray posterior envelopes, and neutrino spectra, are CNN predictions; no spectrum is checked against SOPRANO after fitting. Because the validation in §3.3 is drawn from the same simulation database used for training, the reported accuracy measures emulator self-consistency rather than agreement with an independent calculation. Since the proton-synchrotron solutions for TXS 0506+059 (Poisson) and PKS 0735+178 lie at log10(B/[G])~2.7-2.9 and log10(γp,max)~8, inside the focused P-syn sampling region, a localized surrogate bias could shift the posterior modes or create the PKS 0735+178 bimodality discussed in §4.3. The authors should run SOPRANO on the best-fit parameters and on a sample of posterior draws, compare the electromagnetic and neutrino spectra, and either propagate surrogate uncertainty into the posteriors or explicitly quantify its effect on the reported parameter constraints.
  3. [§4.2-4.3] The astrophysical conclusions rest on several ad hoc choices that are not stress-tested: the assumed two-point neutrino flux at 183 TeV and 4.3 PeV with 10% uncertainty in the Gaussian likelihood, the one-year/one-event IceCube assumption in the Poisson likelihood, and the fixed log10(γe,min)=2.0 in the Poisson runs. The TXS 0506+059 result changes from a hybrid to a proton-synchrotron interpretation when the neutrino likelihood is changed (Table 2), so the model-selection statement is sensitive to exactly these choices. The authors should add sensitivity tests over exposure time, event count, and γe,min priors, and state which of the reported conclusions are robust to these choices.
minor comments (5)
  1. [Figure 1 caption] The caption states that the results have 'great accuracy,' but the reported average R2=0.66 is modest; please either provide stronger region-specific metrics or soften the claim to match the quantitative results.
  2. [§4.2] The text states that Lp=1.5e51 erg/s is at the 'upper boundary of the parameter range used to train' the network, but Table 1 lists the maximum as log10(Lp)=52, which is a factor of several above the fitted value; please clarify which boundary is meant.
  3. [§4.1, Eq. (5)] The Poisson likelihood expression as written, log10 L = 2Σ(t mi) - Si log10(t mi) + log10(Si!), does not match the standard Cash statistic convention; please clarify the definition of L, the role of the factor 2, and the units of t mi.
  4. [Throughout] The text alternates between 'P-sync' and 'P-syn'; please use a single abbreviation consistently.
  5. [§5] The Data Availability statement says the network 'can be shared on a reasonable request' while §5 says it is publicly available through MMDC; please make the accessibility statement consistent.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: CNN emulation of SOPRANO is validated on held-out SOPRANO spectra and applied to external observed SEDs; remaining concerns are accuracy/calibration risks, not circularity.

full rationale

The paper's derivation chain is: SOPRANO computes synthetic EM and neutrino spectra from a kinetic model (Eqs. 1-4); a CNN is trained to map the 10 model parameters to those spectra; the CNN is then used inside a Bayesian fit to observed SEDs of TXS 0506+059 and PKS 0735+178. Validation on a held-out split of the same SOPRANO database is the appropriate test of an emulator's interpolation accuracy; it measures the CNN's fidelity to its target code, which is exactly the claim being made ('effectively reproducing electromagnetic and neutrino emissions' means reproducing SOPRANO's outputs, not independently establishing blazar physics). The application to real observational data is an external benchmark that was not used to train the CNN, so the astrophysical fits do not reduce to the training inputs. Self-citations (Bégué et al. 2024, Sahakyan et al. 2024b for the CNN architecture; Gasparyan et al. 2022 for SOPRANO) are methodological and code references rather than load-bearing evidence for the hadronic emulator's validity; the governing equations are stated in the paper, and no uniqueness theorem or ansatz is smuggled in via citation. The paper itself flags model limitations (no external photon fields, and the PKS 0735+178 P-syn/hybrid bimodality as data-driven ambiguity). The skeptical concern that surrogate error in the posterior region is unquantified (validation R2 = 0.66, no direct SOPRANO re-evaluation of best-fit SEDs) is a legitimate accuracy and uncertainty-propagation risk, but it is not circularity: the CNN predictions are not identical to the fitted inputs by construction, and the observed SEDs are independent of the training database. Therefore no self-definitional, fitted-input-as-prediction, or self-citation-load-bearing circular step is present.

Assumptions & free parameters 12 free parameters · 7 assumptions · 0 invented entities

The central claim rests on the SOPRANO simulator as ground truth, on the representativeness of the Latin hypercube training sample, and on a set of one-zone jet assumptions (uniform B, delta=Gamma, no external photon fields). The 10 physical parameters are fit to data in the application section; the assumed neutrino flux and one-year exposure are hand-chosen inputs. No new physical entities are introduced.

free parameters (12)
  • Doppler factor delta = TXS Gaussian: 15.49; TXS Poisson: 23.18; PKS Poisson: 26.00
    Free parameter in the model, sampled in the Bayesian fit.
  • Blob radius R = 10^17.76 cm (TXS Gaussian), 10^14.53 cm (TXS Poisson), 10^14.55 cm (PKS)
    Free parameter controlling compactness and cooling timescales.
  • Magnetic field B = 10^-1.52 G, 10^2.73 G, 10^2.88 G
    Free parameter governing synchrotron and cooling processes.
  • Electron injection index pe = 1.77, 2.87, 2.62
    Free parameter for the injected electron spectrum.
  • Proton injection index pp = 2.03, 2.00, 1.87
    Free parameter for the injected proton spectrum.
  • Minimum electron Lorentz factor gamma_e,min = 10^1.52 (TXS Gaussian); fixed to 100 in Poisson fits
    Restricted or fixed because the data are not constraining; this is a post-hoc choice.
  • Maximum electron Lorentz factor gamma_e,max = 10^4.76, 10^3.25, 10^3.10
    Free parameter for the electron cutoff energy.
  • Maximum proton Lorentz factor gamma_p,max = 10^6.37, 10^8.00, 10^7.95
    Free parameter for the proton cutoff energy, critical for proton-synchrotron emission.
  • Electron luminosity Le = 10^46.50, 10^43.99, 10^44.61 erg/s
    Free parameter setting the electron injection normalization.
  • Proton luminosity Lp = 10^51.18, 10^46.69, 10^46.91 erg/s
    Free parameter setting the proton injection normalization and neutrino output.
  • Assumed neutrino flux for Gaussian likelihood = 1e-12 erg cm^-2 s^-1 at 183 TeV and 4.3 PeV
    Chosen by hand from the IceCube 7.5-year upper limit, not measured; used as data in the fit.
  • Assumed IceCube exposure and event count for Poisson likelihood = one event over one year
    Assumed scenario, not the actual 0.5-year or 7.5-year exposures discussed for TXS 0506+059.
assumptions (7)
  • domain assumption SOPRANO's kinetic equations (Equations 3 and 4) correctly describe electron, proton, photon, and secondary evolution in a one-zone jet.
    The CNN is trained on SOPRANO output; if SOPRANO is wrong, the surrogate inherits the error. The paper cites Gasparyan et al. 2022 for the code but provides no independent benchmark.
  • domain assumption The system reaches equilibrium at t = 4 t_dyn with negligible spectral variation.
    Used to justify using equilibrium spectra as training targets; stated in Section 2.
  • domain assumption One-zone spherical emitting region with uniform B, delta = Gamma, no adiabatic losses, and no external photon fields.
    This is the physical model behind all fits; the paper itself notes external photon fields are a limitation.
  • standard math Latin hypercube sampling with the stated parameter ranges provides representative coverage of the 10-dimensional parameter space.
    The training distribution is assumed to be sufficient for the CNN to interpolate across the full domain.
  • domain assumption The CNN architecture and L1 training on spectra plus derivatives generalize to unseen parameter combinations.
    The reported R2=0.66 on held-out spectra is the only evidence; no error propagation into posteriors is given.
  • domain assumption IceCube effective area from Blaufuss et al. 2019 and quasi-two-neutrino oscillation mixing fractions apply.
    Used to convert predicted neutrino flux into expected event counts in the Poisson likelihood.
  • domain assumption The EBL absorption model of Domínguez et al. 2011 is correct.
    Applied to all synthetic spectra before comparison with observed gamma-ray data.

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Pith. "Pith review of Modeling blazar broadband emission with convolutional neural networks -- III. proton synchrotron and hybrid models." pith.science (2026). https://pith.science/paper/Q32EYOYY

@misc{pith2026250623885,
  author       = {Pith},
  title        = {Pith review of: Modeling blazar broadband emission with convolutional neural networks -- III. proton synchrotron and hybrid models},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/Q32EYOYY}},
  note         = {Machine review of arXiv:2506.23885}
}
read the original abstract

Modeling the broadband emission of blazars has become increasingly challenging with the advent of multimessenger observations. Building upon previous successes in applying convolutional neural networks (CNNs) to leptonic emission scenarios, we present an efficient CNN-based approach for modeling blazar emission under proton synchrotron and hybrid lepto-hadronic frameworks. Our CNN is trained on extensive numerical simulations generated by SOPRANO, which span a comprehensive parameter space accounting for the injection and all significant cooling processes of electrons and protons. The trained CNN captures complex interactions involving both primary and secondary particles, effectively reproducing electromagnetic and neutrino emissions. This allows for rapid and thorough exploration of the parameter space characteristic of hadronic and hybrid emission scenarios. The effectiveness of the trained CNN is demonstrated through fitting the spectral energy distributions of two prominent blazars, TXS 0506+059 and PKS 0735+178, both associated with IceCube neutrino detections. The modeling is conducted under assumptions of constant neutrino flux across distinct energy ranges, as well as by adopting a fitting that incorporates the expected neutrino event count through a Poisson likelihood method. The trained CNN is integrated into the Markarian Multiwavelength Data Center (MMDC; https://www.mmdc.am), offering a robust tool for the astrophysical community to explore blazar jet physics within a hadronic framework.

Figures

Figures reproduced from arXiv: 2506.23885 by the authors.

Figure 1
Figure 1. Comparison between spectra (arbitrary unit) calculated by the CNN and from the training database (two left-most columns) or the validation database (two right-most columns). Each line corresponds to a different parameter space. As can be seen from this figure, the CNN results matches those from the database, demonstrating that this approach produces results with a great accuracy. 4. APPLICATIONS: MODELING MULTIMESSE… view at source ↗
Figure 2
Figure 2. Broadband SED of TXS 0506+059 during the IceCube-170922A neutrino event. The observed data are shown in blue, while the model corresponding to the maximum likelihood parameters is shown in red (dashed red line is the corresponding neutrino spectrum). Model uncertainties are represented in gray, indicating a subset of spectra drawn from the posterior distribution. The model calculations account for EBL absorption usi… view at source ↗
Figure 3
Figure 3. Broadband SED of PKS 0735+178 during the flaring state coincident with the IceCube-211208A event. The fit is performed with a Poisson likelihood for the neutrino and assumes the detection of one neutrino event by IceCube over a one-year-long exposure. The color coding is the same as in [PITH_FULL_IMAGE:figures/full_fig_p011_3.png] view at source ↗
Figures from the paper (3 more)
Figure 4
Figure 4. Figure 4: Posterior distributions of model parameters for TXS 0506+059 during the observation of the IceCube-170922A event, assuming an E −2 ν neutrino spectrum with a flux of ∼ 10−12 erg cm−2 s −1 between energies 183 TeV and 4.3 PeV. APPENDIX A. PARAMETER POSTERIOR FOR TXS 050…
Figure 5
Figure 5. Figure 5: Same as in [PITH_FULL_IMAGE:figures/full_fig_p016_5.png]
Figure 6
Figure 6. Figure 6: Posterior distributions of model parameters for PKS 0735+178 during its multiwavelength flaring period coinciding with the observation of IceCube-211208A. The fit was performed using a Poisson likelihood for the neutrino and assuming the detection by IceCube of one neu…

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Works this paper leans on

62 extracted references · 17 canonical work pages

  1. [1]

    E,u mҢTQB u UH# 9 l65̚V ] EX #QH K](M# m:!y -Qӄkj YHgꆮ֮3 +آ< : ڣ -6 Fd fY[_ēfVw | VSv

    thebibliography [1] 20pt to REFERENCES 6pt =0pt -12pt 10pt plus 3pt =0pt =0pt =1pt plus 1pt =0pt =0pt -12pt =13pt plus 1pt =20pt =13pt plus 1pt \@M =10000 =-1.0em =0pt =0pt 0pt =0pt =1.0em @enumiv\@empty 10000 10000 `\.\@m \@noitemerr \@latex@warning Empty `thebibliography' environment \@ifnextchar \@reference \@latexerr Missing key on reference command E...

  2. [2]

    Abe H., et al., 2023, @doi [ ] 10.3847/1538-4365/acc181 , https://ui.adsabs.harvard.edu/abs/2023ApJS..266...37A 266, 37

  3. [3]

    Acharyya A., et al., 2023, @doi [ ] 10.3847/1538-4357/ace327 , https://ui.adsabs.harvard.edu/abs/2023ApJ...954...70A 954, 70

  4. [4]

    Ansoldi S., et al., 2018, @doi [ ] 10.3847/2041-8213/aad083 , http://adsabs.harvard.edu/abs/2018ApJ...863L..10A 863, L10

  5. [5]

    K., 2008, @doi [ ] 10.1016/j.physrep.2007.10.006 , https://ui.adsabs.harvard.edu/abs/2008PhR...458..173B 458, 173

    Becker J. K., 2008, @doi [ ] 10.1016/j.physrep.2007.10.006 , https://ui.adsabs.harvard.edu/abs/2008PhR...458..173B 458, 173

  6. [6]

    B \'e gu \'e D., Sahakyan N., Dereli-B \'e gu \'e H., Giommi P., Gasparyan S., Khachatryan M., Casotto A., Pe'er A., 2024, @doi [ ] 10.3847/1538-4357/ad19cf , https://ui.adsabs.harvard.edu/abs/2024ApJ...963...71B 963, 71

  7. [7]

    The Next Generation of IceCube Realtime Neutrino Alerts

    Blaufuss E., Kintscher T., Lu L., Tung C. F., 2019, in 36th International Cosmic Ray Conference (ICRC2019). p. 1021 ( @eprint arXiv 1908.04884 ), @doi 10.22323/1.358.01021

  8. [8]

    M., 2000, @doi [ ] 10.1086/317791 , https://ui.adsabs.harvard.edu/abs/2000ApJ...545..107B 545, 107

    B a \.z ejowski M., Sikora M., Moderski R., Madejski G. M., 2000, @doi [ ] 10.1086/317791 , https://ui.adsabs.harvard.edu/abs/2000ApJ...545..107B 545, 107

Show all 62 references
  1. [9]

    D., Marscher A

    Bloom S. D., Marscher A. P., 1996, @doi [ ] 10.1086/177092 , https://ui.adsabs.harvard.edu/abs/1996ApJ...461..657B 461, 657

  2. [10]

    M., van Leeuwen J., 2023, @doi [ ] 10.1017/pasa.2023.32 , https://ui.adsabs.harvard.edu/abs/2023PASA...40...30B 40, e030

    Boersma O. M., van Leeuwen J., 2023, @doi [ ] 10.1017/pasa.2023.32 , https://ui.adsabs.harvard.edu/abs/2023PASA...40...30B 40, e030

  3. [11]

    B \"o ttcher M., Reimer A., Sweeney K., Prakash A., 2013, @doi [ ] 10.1088/0004-637X/768/1/54 , http://adsabs.harvard.edu/abs/2013ApJ...768...54B 768, 54

  4. [12]

    M., 2023, @doi [The Journal of Open Source Software] 10.21105/joss.04969 , https://ui.adsabs.harvard.edu/abs/2023JOSS....8.4969B 8, 4969

    Burgess J. M., 2023, @doi [The Journal of Open Source Software] 10.21105/joss.04969 , https://ui.adsabs.harvard.edu/abs/2023JOSS....8.4969B 8, 4969

  5. [13]

    Cash W., 1979, @doi [ ] 10.1086/156922 , https://ui.adsabs.harvard.edu/abs/1979ApJ...228..939C 228, 939

  6. [14]

    Cerruti M., Zech A., Boisson C., Emery G., Inoue S., Lenain J.-P., 2019, @doi [ ] 10.1093/mnrasl/sly210 , https://ui.adsabs.harvard.edu/abs/2019MNRAS.483L..12C 483, L12

  7. [15]

    D., Schlickeiser R., 1994, @doi [ ] 10.1086/191929 , https://ui.adsabs.harvard.edu/abs/1994ApJS...90..945D 90, 945

    Dermer C. D., Schlickeiser R., 1994, @doi [ ] 10.1086/191929 , https://ui.adsabs.harvard.edu/abs/1994ApJS...90..945D 90, 945

  8. [16]

    D., Schlickeiser R., Mastichiadis A., 1992, , https://ui.adsabs.harvard.edu/abs/1992A&A...256L..27D 256, L27

    Dermer C. D., Schlickeiser R., Mastichiadis A., 1992, , https://ui.adsabs.harvard.edu/abs/1992A&A...256L..27D 256, L27

  9. [17]

    Dom \' nguez A., et al., 2011, @doi [ ] 10.1111/j.1365-2966.2010.17631.x , https://ui.adsabs.harvard.edu/abs/2011MNRAS.410.2556D 410, 2556

  10. [18]

    A., Suvorova O., Baikal-GVD Collaboration 2021, The Astronomer's Telegram, https://ui.adsabs.harvard.edu/abs/2021ATel15112....1D 15112, 1

    Dzhilkibaev Z. A., Suvorova O., Baikal-GVD Collaboration 2021, The Astronomer's Telegram, https://ui.adsabs.harvard.edu/abs/2021ATel15112....1D 15112, 1

  11. [19]

    arXiv:1802.05781

    Fantini G., Gallo Rosso A., Vissani F., Zema V., 2018, @doi [arXiv e-prints] 10.48550/arXiv.1802.05781 , https://ui.adsabs.harvard.edu/abs/2018arXiv180205781F p. arXiv:1802.05781

  12. [20]

    P., Bridges M., 2009, @doi [ ] 10.1111/j.1365-2966.2009.14548.x , http://adsabs.harvard.edu/abs/2009MNRAS.398.1601F 398, 1601

    Feroz F., Hobson M. P., Bridges M., 2009, @doi [ ] 10.1111/j.1365-2966.2009.14548.x , http://adsabs.harvard.edu/abs/2009MNRAS.398.1601F 398, 1601

  13. [21]

    Filippini F., et al., 2022, The Astronomer's Telegram, https://ui.adsabs.harvard.edu/abs/2022ATel15290....1F 15290, 1

  14. [22]

    Gao S., Fedynitch A., Winter W., Pohl M., 2019, @doi [Nature Astronomy] 10.1038/s41550-018-0610-1 , https://ui.adsabs.harvard.edu/abs/2019NatAs...3...88G 3, 88

  15. [23]

    Gasparyan S., B \'e gu \'e D., Sahakyan N., 2022, @doi [ ] 10.1093/mnras/stab2688 , https://ui.adsabs.harvard.edu/abs/2022MNRAS.509.2102G 509, 2102

  16. [24]

    Ghisellini G., Maraschi L., Treves A., 1985, , https://ui.adsabs.harvard.edu/abs/1985A&A...146..204G 146, 204

  17. [25]

    Giommi P., Padovani P., Oikonomou F., Glauch T., Paiano S., Resconi E., 2020, @doi [ ] 10.1051/0004-6361/202038423 , https://ui.adsabs.harvard.edu/abs/2020A&A...640L...4G 640, L4

  18. [26]

    IceCube Collaboration 2021, GRB Coordinates Network, https://ui.adsabs.harvard.edu/abs/2021GCN.31191....1I 31191, 1

  19. [27]

    IceCube Collaboration et al., 2018a, @doi [Science] 10.1126/science.aat1378 , http://adsabs.harvard.edu/abs/2018Sci...361.1378I 361, eaat1378

  20. [28]

    IceCube Collaboration et al., 2018b, @doi [Science] 10.1126/science.aat2890 , https://ui.adsabs.harvard.edu/abs/2018Sci...361..147I 361, 147

  21. [29]

    Keivani A., et al., 2018, @doi [ ] 10.3847/1538-4357/aad59a , http://adsabs.harvard.edu/abs/2018ApJ...864...84K 864, 84

  22. [30]

    Krau F., et al., 2020, @doi [ ] 10.1093/mnras/staa2148 , https://ui.adsabs.harvard.edu/abs/2020MNRAS.497.2553K 497, 2553

  23. [31]

    Liao N.-H., et al., 2022, @doi [ ] 10.3847/2041-8213/ac756f , https://ui.adsabs.harvard.edu/abs/2022ApJ...932L..25L 932, L25

  24. [32]

    Mannheim K., 1993, , http://adsabs.harvard.edu/abs/1993A

  25. [33]

    L., 1989, , http://adsabs.harvard.edu/abs/1989A

    Mannheim K., Biermann P. L., 1989, , http://adsabs.harvard.edu/abs/1989A

  26. [34]

    Maraschi L., Ghisellini G., Celotti A., 1992, @doi [ ] 10.1086/186531 , https://ui.adsabs.harvard.edu/abs/1992ApJ...397L...5M 397, L5

  27. [35]

    D., Beckman R

    McKay M. D., Beckman R. J., Conover W. J., 2000, Technometrics, 42, 55

  28. [36]

    J., 2001, @doi [Astroparticle Physics] 10.1016/S0927-6505(00)00141-9 , https://ui.adsabs.harvard.edu/abs/2001APh....15..121M 15, 121

    M \"u cke A., Protheroe R. J., 2001, @doi [Astroparticle Physics] 10.1016/S0927-6505(00)00141-9 , https://ui.adsabs.harvard.edu/abs/2001APh....15..121M 15, 121

  29. [37]

    J., Engel R., Rachen J

    M \"u cke A., Protheroe R. J., Engel R., Rachen J. P., Stanev T., 2003, @doi [Astroparticle Physics] 10.1016/S0927-6505(02)00185-8 , http://adsabs.harvard.edu/abs/2003APh....18..593M 18, 593

  30. [38]

    Murase K., Oikonomou F., Petropoulou M., 2018, @doi [ ] 10.3847/1538-4357/aada00 , http://adsabs.harvard.edu/abs/2018ApJ...865..124M 865, 124

  31. [39]

    Oikonomou F., Petropoulou M., Murase K., Tohuvavohu A., Vasilopoulos G., Buson S., Santander M., 2021, @doi [ ] 10.1088/1475-7516/2021/10/082 , https://ui.adsabs.harvard.edu/abs/2021JCAP...10..082O 2021, 082

  32. [40]

    Omeliukh A., et al., 2025, @doi [ ] 10.1051/0004-6361/202452143 , https://ui.adsabs.harvard.edu/abs/2025A&A...695A.266O 695, A266

  33. [41]

    Padovani P., Giommi P., Resconi E., Glauch T., Arsioli B., Sahakyan N., Huber M., 2018, @doi [ ] 10.1093/mnras/sty1852 , https://ui.adsabs.harvard.edu/abs/2018MNRAS.480..192P 480, 192

  34. [42]

    Padovani P., Oikonomou F., Petropoulou M., Giommi P., Resconi E., 2019, @doi [ ] 10.1093/mnrasl/slz011 , https://ui.adsabs.harvard.edu/abs/2019MNRAS.484L.104P 484, L104

  35. [43]

    Padovani P., Boccardi B., Falomo R., Giommi P., 2022, @doi [ ] 10.1093/mnras/stac376 , https://ui.adsabs.harvard.edu/abs/2022MNRAS.511.4697P 511, 4697

  36. [44]

    Paiano S., Falomo R., Treves A., Scarpa R., 2018, @doi [ ] 10.3847/2041-8213/aaad5e , https://ui.adsabs.harvard.edu/abs/2018ApJ...854L..32P 854, L32

  37. [45]

    Paliya V. S., B \"o ttcher M., Olmo-Garc \' a A., Dom \' nguez A., Gil de Paz A., Franckowiak A., Garrappa S., Stein R., 2020, @doi [ ] 10.3847/1538-4357/abb46e , https://ui.adsabs.harvard.edu/abs/2020ApJ...902...29P 902, 29

  38. [46]

    B., Novoseltsev Y

    Petkov V. B., Novoseltsev Y. F., Novoseltseva R. V., Baksan Underground Scintillation Telescope Group 2021, The Astronomer's Telegram, https://ui.adsabs.harvard.edu/abs/2021ATel15143....1P 15143, 1

  39. [47]

    Petropoulou M., Mastichiadis A., 2015, @doi [ ] 10.1093/mnras/stu2364 , https://ui.adsabs.harvard.edu/abs/2015MNRAS.447...36P 447, 36

  40. [48]

    Petropoulou M., Oikonomou F., Mastichiadis A., Murase K., Padovani P., Vasilopoulos G., Giommi P., 2020, @doi [ ] 10.3847/1538-4357/aba8a0 , https://ui.adsabs.harvard.edu/abs/2020ApJ...899..113P 899, 113

  41. [49]

    Prince R., Das S., Gupta N., Majumdar P., Czerny B., 2024, @doi [ ] 10.1093/mnras/stad3804 , https://ui.adsabs.harvard.edu/abs/2024MNRAS.527.8746P 527, 8746

  42. [50]

    Righi C., Tavecchio F., Pacciani L., 2019, @doi [ ] 10.1093/mnras/sty3072 , https://ui.adsabs.harvard.edu/abs/2019MNRAS.484.2067R 484, 2067

  43. [51]

    S., Garrappa S., Omeliukh A., Franckowiak A., Winter W., 2024a, @doi [ ] 10.1051/0004-6361/202347540 , https://ui.adsabs.harvard.edu/abs/2024A&A...681A.119R 681, A119

    Rodrigues X., Paliya V. S., Garrappa S., Omeliukh A., Franckowiak A., Winter W., 2024a, @doi [ ] 10.1051/0004-6361/202347540 , https://ui.adsabs.harvard.edu/abs/2024A&A...681A.119R 681, A119

  44. [52]

    Rodrigues X., Karl M., Padovani P., Giommi P., Paiano S., Falomo R., Petropoulou M., Oikonomou F., 2024b, @doi [ ] 10.1051/0004-6361/202450592 , https://ui.adsabs.harvard.edu/abs/2024A&A...689A.147R 689, A147

  45. [53]

    Sahakyan N., 2018, @doi [ ] 10.3847/1538-4357/aadade , http://adsabs.harvard.edu/abs/2018ApJ...866..109S 866, 109

  46. [54]

    Sahakyan N., 2019, @doi [ ] 10.1051/0004-6361/201834606 , https://ui.adsabs.harvard.edu/abs/2019A&A...622A.144S 622, A144

  47. [55]

    Sahakyan N., Giommi P., Padovani P., Petropoulou M., B \'e gu \'e D., Boccardi B., Gasparyan S., 2023, @doi [ ] 10.1093/mnras/stac3607 , https://ui.adsabs.harvard.edu/abs/2023MNRAS.519.1396S 519, 1396

  48. [56]

    Sahakyan N., et al., 2024a, @doi [ ] 10.3847/1538-3881/ad8231 , https://ui.adsabs.harvard.edu/abs/2024AJ....168..289S 168, 289

  49. [57]

    Sahakyan N., et al., 2024b, @doi [ ] 10.3847/1538-4357/ad5351 , https://ui.adsabs.harvard.edu/abs/2024ApJ...971...70S 971, 70

  50. [58]

    C., Rees M

    Sikora M., Begelman M. C., Rees M. J., 1994, @doi [ ] 10.1086/173633 , https://ui.adsabs.harvard.edu/abs/1994ApJ...421..153S 421, 153

  51. [59]

    I., 2024, @doi [ ] 10.1051/0004-6361/202348566 , https://ui.adsabs.harvard.edu/abs/2024A&A...683A.185T 683, A185

    Tzavellas A., Vasilopoulos G., Petropoulou M., Mastichiadis A., Stathopoulos S. I., 2024, @doi [ ] 10.1051/0004-6361/202348566 , https://ui.adsabs.harvard.edu/abs/2024A&A...683A.185T 683, A185

  52. [60]

    M., Padovani P., 1995, @doi [ ] 10.1086/133630 , https://ui.adsabs.harvard.edu/abs/1995PASP..107..803U 107, 803

    Urry C. M., Padovani P., 1995, @doi [ ] 10.1086/133630 , https://ui.adsabs.harvard.edu/abs/1995PASP..107..803U 107, 803

  53. [61]

    A., 2016, Quality and reliability engineering international, 32, 1975

    Viana F. A., 2016, Quality and reliability engineering international, 32, 1975

  54. [62]

    F., Sarin N., 2025, @doi [ ] 10.1093/mnras/staf623 , https://ui.adsabs.harvard.edu/abs/2025MNRAS.539.3319W 539, 3319

    Wallace W. F., Sarin N., 2025, @doi [ ] 10.1093/mnras/staf623 , https://ui.adsabs.harvard.edu/abs/2025MNRAS.539.3319W 539, 3319

Pith tools

Reviewed August 6, 2026 · model on record in the stance chip above.