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Are Kronberger 80 and/or Kronberger 82 regions PeVatron candidates for LHAASO J2108+5157?

T0 review · 2 major / 6 minor · reviewed 2026-08-16 · deepseek-v4-flash

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Pith's one-line read Kronberger 80 and Kronberger 82 do not contain enough massive stars to be the PeVatrons behind LHAASO J2108+5157.

desk verdict A useful negative result with one overconfident conclusion: the photometry rules out OB-star wind PeVatrons in Kron 80/82, but it does not disqualify the embedded SNR/PWN scenarios the paper itself leaves open. read the letter →

arxiv 2504.15446 v2 pith:YNZBZAH2 submitted 2025-04-21 astro-ph.HE astro-ph.GAastro-ph.SR

Akash Gupta , Eduardo De La Fuente , Ram K. Yadav , Alicia Porras , Saurabh Sharma , Sei Kato , Daniel Tafoya , Miguel A. Trinidad
show 8 more authors
Alberto Nigoche-Netro Harold E. Viveros Kazumasa Kawata Hiromasa Suzuki Munehiro Ohnishi Ivan Toledano-Juarez Takashi Sako Masato Takita
This is my paper · ORCID
classification astro-ph.HEastro-ph.GAastro-ph.SR
keywords PeVatronsLHAASOJ2108+5157Kronberger8082star-formingregionsO-typestarsinfraredphotometrygamma-raysources
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 asks whether the star-forming clusters Kronberger 80 and Kronberger 82, lying in the field of the unidentified gamma-ray source LHAASO J2108+5157, could be the PeVatrons accelerating the cosmic rays that produce the observed sub-PeV emission. It builds a stellar census from near- and mid-infrared photometry and compares it with Cygnus OB2, the only star cluster already confirmed as a PeVatron. The census finds just one O-type star in each Kronberger cluster, against hundreds in Cygnus OB2, and low total cluster masses. The paper concludes that neither cluster has enough massive stars and stellar winds to qualify as a PeVatron, and that both are young star-forming regions, not evolved clusters. If this is right, the origin of LHAASO J2108+5157 remains unknown and the search must move to other candidate accelerators.

What carries the argument

The decisive instrument is the infrared color-color and color-magnitude census: 2MASS JHK diagrams with reddening vectors and a ZAMS spectral-type track, plus all-WISE color-color diagrams that classify young stellar objects into Class I, II, III and transition disks. These diagrams put every detected star at its extinction-corrected spectral position, so a deficiency of O-type stars becomes visible directly; the census carries the rejection of both clusters. King-profile fits to the radial stellar density give the cluster radii, Gaia and Bayesian distance estimates fix where each cluster sits along the line of sight, and PARSEC isochrones supply the ages that characterize the clusters as forming rather than evolved.

What would settle it

A spectroscopic survey of candidate massive stars in both cluster fields, reaching the O-star locus at visual extinctions above 15 magnitudes, would settle the matter: detecting several O-type stars beyond the single photometric candidate in each cluster would overturn the claim that their stellar content disqualifies them as PeVatrons.

Watch

Extended reading notes

Core claim

On its own terms, the paper establishes that Kronberger 80 and Kronberger 82 are not viable PeVatron counterparts to LHAASO J2108+5157. Kronberger 80 is placed at about 10 kpc, far beyond the gamma-ray source's distance, with a radius of 2.5 arcminutes and an age of roughly 5 to 12.6 Myr. Kronberger 82 is re-estimated to lie at 1.63 +/- 0.05 kpc, inside the Cygnus OB7 cloud, with a radius of 2.0 arcminutes and an age below 5 Myr. In both clusters the infrared color-magnitude diagrams reveal only one O-type star each, and the WISE young-stellar-object counts are dominated by low-mass Class II and transition-disk objects. The paper therefore rejects both clusters as PeVatrons on stellar-content grounds: without a population of massive stars there are no strong stellar winds or intense UV radiation to accelerate particles, in contrast with Cygnus OB2.

Load-bearing premise

The argument assumes the near-infrared stellar census is complete enough that no embedded massive O-type stars are hidden in Kronberger 80 or Kronberger 82 at their adopted distances and extinctions.

Editorial extensions

If this is right

  • Neither Kronberger 80 nor Kronberger 82 can serve as the accelerator behind LHAASO J2108+5157, so the search for its counterpart must target other objects, such as an undetected supernova remnant.
  • Kronberger 82's revised distance of about 1.6 kpc places it inside the Cygnus OB7 molecular cloud, matching J2108's position and distance even though its low stellar mass rules it out as the engine.
  • The diffusion scenario from the nearest known PeVatron, Cygnus OB2, would require a nucleon density above roughly $1.9 \times 10^4$ cm$^{-3}$ in the J2108 cloud, while the reported molecular densities are 30 to 133 cm$^{-3}$, making that explanation unlikely.
  • Even the whole 0.7-degree J2108 region contains only about 12 O-type stars, roughly one hundredth of Cygnus OB2's count, so no massive star cluster comparable to Cygnus OB2 is present anywhere in the field.

Reading between the lines

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

  • A hidden population of O stars could still exist behind the highest-extinction material, since the photometric census has no stated completeness limit and no spectroscopic confirmation; deeper mid-infrared or radio-recombination-line surveys would test this directly.
  • The comparison with Cygnus OB2 may set a very high bar: Cygnus OB2 is a super-PeVatron candidate with thousands of OB stars, and a smaller cluster might still produce observable gamma rays even if it cannot reach 100 TeV; the paper does not quantify a minimum O-star count needed for PeVatron status.
  • The most massive young stellar object in IRAS 21078+5211, around 6 to 8 solar masses, implies that Kronberger 82 may never form O stars, but this relies on a single accretion estimate; a direct census of embedded protostars would verify it.
  • If no PeVatron is ever found in the field, the J2108 emission may force a leptonic interpretation or a revised cosmic-ray diffusion model; the appendix's density estimate is a useful first check but neglects proton escape and diffuse backgrounds.
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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

2 major / 6 minor

Summary. The paper investigates whether the star-forming regions Kronberger 80 and Kronberger 82, which lie in the field of the LHAASO J2108+5157 sub-PeV gamma-ray source, can be considered PeVatron counterparts. Using 2MASS, WISE, Gaia DR3, and IPHAS photometry, the authors estimate cluster centers and radii with KDE and King-profile fits, derive a distance of 10 kpc for Kron 80 from the literature and 1.63 +/- 0.05 kpc for Kron 82 from Bayesian kinematic distances, Gaia parallaxes, and a maser parallax, and obtain ages of 5-12.6 Myr and <5 Myr respectively. From near- and mid-infrared color-color and color-magnitude diagrams, they report only one O-type star in each cluster, compare the YSO content with Cygnus OB2, and conclude that the stellar content of the two Kronberger regions is too poor to power PeVatron emission, disqualifying them as counterparts of J2108. An appendix estimates the nucleon density required if the nearest known PeVatron, Cygnus OB2, were responsible for the J2108 emission.

Significance. If the negative conclusion holds, the paper removes the originally proposed optical/IR cluster counterparts for LHAASO J2108+5157 and sharpens the search for the true accelerator, which is valuable for the PeVatron community. The work's strengths are its use of independent archival photometry (2MASS, WISE, Gaia DR3), the quantitative distance estimate for Kron 82 with a maser cross-check, and the explicit comparison with Cygnus OB2. The analysis is not circular: the adopted molecular-cloud distances and densities from earlier papers are inputs, not outputs, of the stellar-content argument. The main weakness is that the demonstrated conclusion concerns the stellar-wind acceleration mechanism, while the text states a categorical disqualification of the clusters as PeVatron candidates even though the embedded-SNR/PWN possibility is explicitly left open.

major comments (2)
  1. [Section 4.4 and Conclusions] The statement that the stellar content 'disqualifies' Kron 80 and Kron 82 as PeVatron candidates overreaches what the analysis shows. The photometric census tests only the Cyg-OB2-like stellar-wind channel, yet Section 4.4 itself concedes that 'an undetected and embedded SNR in the region is conceivable; perhaps an SNR from a massive star (age ~ 10^6 yr) in the J2108 region is producing cosmic rays.' A core-collapse SNR or pulsar wind nebula would not require a present-day O star, so the absence of massive stars does not rule out those accelerator classes. The conclusions should be reworded to state that the stellar-wind mechanism is strongly disfavored, while embedded SNR/PWN scenarios remain viable, rather than claiming the regions are disqualified as PeVatron candidates.
  2. [Section 4.1 and Fig. 5] The one-O-star-per-cluster result is the load-bearing evidence for the paper's central claim, but it rests entirely on 2MASS/WISE/Gaia photometry without spectroscopic confirmation and without a stated completeness limit. At the adopted 10 kpc distance of Kron 80, with foreground AV up to ~15 mag and possibly higher for embedded stars, the paper should quantify the 2MASS K-band sensitivity limit expressed as the maximum AV at which an O star would still be detected at that distance, and should flag the single O-star classifications as photometric estimates subject to contamination and extinction effects. Without this quantitative completeness argument, the census cannot exclude a hidden massive population as firmly as the text implies.
minor comments (6)
  1. [Section 3.1 and elsewhere] There are several typographical errors that should be corrected: 'Two–Mircron' should be 'Two-Micron', 'all bads' should be 'all bands', 'Refered' should be 'Referred', 'LHAASO J2108+5156' in Section 4.4 should be 'J2108+5157', and 'J2107+5158' in Section 5 should be 'J2108+5157'.
  2. [Section 2.1] The sentence introducing 'dark source' and then stating that J2108 'was not classified as a dark source' is confusing; the authors should clarify why a source without a cataloged counterpart is not considered a dark source in the Cao et al. (2024) sense.
  3. [Section 4.3 and Table 2] The age of Kron 82 is imported from Moscadelli et al. (2021) because IPHAS data could not be used, and the Kron 82 cluster mass of 60-100 M_sun follows from Eq. (4) using the most massive YSO in the associated IRAS source. The text should state more explicitly that these parameters are not independently derived in this work, and should note how their uncertainty affects the 'formation rather than evolution' characterization.
  4. [Section 4.1] The O-star counts for J2108 (12 sources) and Cygnus OB2 (1200 sources) are also photometric estimates from CMD positions, not spectroscopically confirmed spectral types; a caveat about binarity, extinction, and field contamination should be added when these numbers are compared.
  5. [Table 1] The YSO counts are based on WISE colors using the Kang et al. (2017) criteria and are presented without uncertainties; a note should be added that at the Kron 80 distance the WISE angular resolution may blend close pairs, and that the counts are subject to the adopted classification boundaries.
  6. [Section 4.4] The claim that 'all candidates originally proposed by Cao et al. (2021b)... have now been quantitatively discarded' is stronger than the evidence presented if Kron 80 and Kron 82 are the only originally proposed candidates; the authors should explicitly list which candidates are meant, or qualify the statement accordingly.

Circularity Check

0 steps flagged · score 0.0 of 10

No material circularity: the PeVatron disqualification rests on independent archival photometry and Gaia/maser astrometry; self-citations are inputs, not outputs.

full rationale

The central claim that Kron 80 and Kron 82 are unlikely PeVatron candidates is derived from archival 2MASS, WISE, IPHAS, and Gaia photometry plus Gaia and VLBI maser distances, not from any parameter fitted to the conclusion or from a self-citation chain. The comparison with Cygnus OB2 is an external benchmark; the inference that a sparse O-star population disfavors a stellar-wind PeVatron is a physical assumption, not a tautology. Self-citations to de la Fuente et al. (2023b,c) supply molecular-line velocities, cloud distances, and nucleon densities that are inputs to the distance estimate and the appendix calculation, but the adopted Kron 82 distance is independently supported by Gaia parallaxes and the maser parallax of [HLB98] Onsala 150, and the cluster rejection does not require those densities. No equation in the paper reduces by construction to an earlier equation or to the paper's own fitted values. For completeness, Appendix A contains two unresolved '?' citations ('According to Fig. 5 of ?' and 'and ? for Cyg-OB2 at ...'), which are missing references rather than circular steps; they should be repaired but do not affect the circularity assessment.

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

The analysis rests on standard assumptions about stellar evolution, extinction, and the necessity of massive stars for PeV acceleration. No new physical entities are introduced. The adopted Kron 80 distance, the choice of the Kron 82 distance peak, and the imported cluster ages are the main externally supplied numbers, alongside published YSO classification boundaries.

free parameters (4)
  • Kron 80 distance = 10 kpc
    Adopted from Cantat-Gaudin & Anders (2020) over older estimates of 5 kpc and 7 kpc; affects the physical radius and the conclusion that Kron 80 is not associated with J2108.
  • Kron 82 distance peak selection = 1.63 +/- 0.05 kpc
    The Bayesian distance calculator yields a 0.66-probability peak at 1.62 kpc and a 0.32-probability peak at 1.28 kpc; the paper adopts the higher-probability peak, which places Kron 82 in Cyg-OB7 and supports potential association with J2108.
  • Kron 80 cluster age = 5 to 12.6 Myr, mean about 8 Myr
    Fitted with PARSEC isochrones to IPHAS data; used for characterization and comparison with Cygnus OB2 but not directly for the PeVatron rejection.
  • Kron 82 cluster age = less than 5 Myr
    Assumed from Moscadelli et al. (2021) because IPHAS-based age estimation was impossible due to extinction; this is an imported fitted value.
assumptions (5)
  • domain assumption A star-forming cluster requires a substantial population of massive O-type or early B-type stars to accelerate cosmic rays to PeV energies via stellar winds; absence of such stars disqualifies it as a PeVatron.
    Underlies the comparison with Cygnus OB2 in Sections 4.1 and 4.4; the paper uses the number of O stars as the decisive criterion for PeVatron candidacy.
  • domain assumption The 2MASS and WISE photometric catalogs are complete enough, at the adopted distances and extinctions, to detect O-type stars and classify young stellar objects in Kron 80 and Kron 82.
    The O-star counts and YSO classifications rest on the color-color and color-magnitude diagrams in Figures 5 and 6; no quantitative completeness limit or spectroscopic confirmation is provided.
  • domain assumption Gaia parallaxes, the Bailer-Jones distance transformation, and the Bayesian distance calculator of Reid et al. (2019) give unbiased distances for Kron 82.
    Used in Section 4.2 to derive the new Kron 82 distance of about 1.63 kpc.
  • domain assumption PARSEC isochrones at solar metallicity, together with the Rieke and Lebofsky (1985) extinction law, adequately model the Kron 80 stellar population.
    Used to derive the age range in Section 4.3 and to draw reddening vectors in the color-color and color-magnitude diagrams.
  • standard math The pion-decay gamma-ray production relation of Aharonian et al. (2019) and the cosmic-ray enhancement factor eta = 2.6 apply in the appendix calculation.
    The appendix density estimate for an external PeVatron origin uses this standard relation and the published LHAASO luminosity, with no quantities fitted in this paper.

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Cite this review

Pith. "Pith review of Are Kronberger 80 and/or Kronberger 82 regions PeVatron candidates for LHAASO J2108+5157?." pith.science (2026). https://pith.science/paper/YNZBZAH2

@misc{pith2026250415446,
  author       = {Pith},
  title        = {Pith review of: Are Kronberger 80 and/or Kronberger 82 regions PeVatron candidates for LHAASO J2108+5157?},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/YNZBZAH2}},
  note         = {Machine review of arXiv:2504.15446}
}
abstract

High-energy gamma rays have been detected in the region of LHAASO~J2108+5157 by the Fermi--LAT, HAWC and LHAASO-KM2A observatories. Cygnus~OB2 in Cygnus--X has been confirmed as the first strong stellar cluster PeVatron in our Galaxy. Thus, the star--forming regions Kronberger~80 and Kronberger~82, located in the field of LHAASO~J2108+5157, are analyzed to evaluate their stellar population and potential as associated PeVatron candidates. A distance of 10~kpc is adopted for Kronberger~80, while $\sim$1.6~kpc is estimated for Kronberger~82. Based on stellar densities, we report that their cluster radii are 2.5$\arcmin$ and 2.0$\arcmin$, while IR photometry reveals poor stellar content in massive O-type stars in both cases. From optical data, the estimation of cluster ages are 5--12.6~Myr and $\lesssim$ 5~Myr, respectively. We conclude that, in contrast to the stellar content of Cygnus~OB2, it is unlikely that Kronberger~80 and Kronberger~82 are PeVatrons associated with LHAASO~J2108+5157. The presence of a PeVatron in this region remains a mystery, but we confirm that the two Kronberger regions are star--forming regions undergoing formation rather than evolution.

Figures

Figures reproduced from arXiv: 2504.15446 by the authors.

Figure 1
Figure 1. Three square degrees infrared images centered at [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. Iso-density plots of Kronberger 80 (left) and Kronberger 82 (right) from 2MASS data. The color bar [PITH_FULL_IMAGE:figures/full_fig_p005_2.png] view at source ↗
Figure 3
Figure 3. King profile fitting for Kronberger 80 (left) and 82 (right). King fit parameters are summarized in [PITH_FULL_IMAGE:figures/full_fig_p006_3.png] view at source ↗
Figures from the paper (7 more)
Figure 4
Figure 4. Figure 4: Top: Gaia color-magnitude diagram for Kronberger 80 (left) and Kronberger 82 (right). Bottom: Respective vector plot diagrams. Alt text: Four diagrams are shown with optical photometric data obtained from the Gaia survey, for the Kronberger 80 and Kronberger 82 regions…
Figure 5
Figure 5. Figure 5: Typical 2MASS color-color (CC) and color-magnitude (CM) diagrams in Bessell & Brett (1988) [PITH_FULL_IMAGE:figures/full_fig_p008_5.png]
Figure 6
Figure 6. Figure 6: Typical all–WISE color-color diagrams for LHAASO J2108+5157 (top), Kronberger 80 (middle) and [PITH_FULL_IMAGE:figures/full_fig_p009_6.png]
Figure 7
Figure 7. Figure 7: Probability density curve for the distance of the source Kronberger 82 obtained from the Bayesian [PITH_FULL_IMAGE:figures/full_fig_p011_7.png]
Figure 8
Figure 8. Figure 8: Gaia parallax error distribution for Kronberger 82. Alt text: Dispersion of error values in the parallax measurement of visible stars in Kronberger 82. 4.3 Cluster Ages For Kron 80, Molina Lera et al. (2019) determined an age between 10 and 30 Myr, by fitting the model…
Figure 9
Figure 9. Figure 9: Location of Kronberger 80 and 82 within our Galaxy. The bars indicate the estimated distance [PITH_FULL_IMAGE:figures/full_fig_p013_9.png]
Figure 10
Figure 10. Figure 10: Optical color-magnitude diagram of Kronberger 80 derived from the INT Photometric H [PITH_FULL_IMAGE:figures/full_fig_p014_10.png]

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Works this paper leans on

83 extracted references · 68 canonical work pages

  1. [1]

    Abe, S., Aguasca-Cabot, A., Agudo, I., et al., 2023, , 673, A75

    2023

  2. [2]

    A., Magic Collaboration , 2023, , 671, A12

    Abe, H., Abe, S., Acciari, V. A., Magic Collaboration , 2023, , 671, A12

    2023

  3. [3]

    U., et al.\ 2023, Nucl

    Abeysekara, A. U., et al.\ 2023, Nucl. Instrum. Methods. Phys. Res. A, 1052, 168253

    2023

  4. [4]

    Astron., 5, 465

    Abeysekara, A.U, et al.\ 2021, Nat. Astron., 5, 465

    work page 2021

  5. [5]

    U., et al.\ 2020, Phys

    Abeysekara, A. U., et al.\ 2020, Phys. Rew. Lett, 124, 021102

    work page 2020

  6. [6]

    A., Abramowski, et al.\ 2016, Nat., 531, 476

    work page 2016

  7. [7]

    A., Ansoldi, S., Antonelli, L

    Acciari, V. A., Ansoldi, S., Antonelli, L. A. et al., 2023, Magic Collaboration, , 670, A8

    work page 2023

  8. [8]

    Ackermann, M., et al.\ 2011, Science, 334, 1103

    work page 2011

Show all 83 references
  1. [9]

    Astron., 3, 561

    Aharonian, F., et al., 2019, Nat. Astron., 3, 561

    2019

  2. [10]

    Astron., 5, 460

    Amenomori, M., et al.\ 2021a, Nat. Astron., 5, 460

  3. [11]

    Amenomori, M., et al.\ 2021b, Phys. Rev. Lett, 126, 141101

  4. [12]

    Amenomori, M., et al.\ 2021c, Phys. Rev. Lett, 127, 031102

  5. [13]

    Amenomori, M., et al.\ 2019, Phys. Rev. Lett, 123, 051101

    2019

  6. [14]

    O.\ 2023, Turk

    Angüner, E. O.\ 2023, Turk. J. Phys., 47, 2

    2023

  7. [15]

    Bailer-Jones, C. A. L.\ 2015, , 127, 994. doi:10.1086/683116

    2015 doi

  8. [16]

    J., Drew, J

    Barentsen, G., Farnhill, H. J., Drew, J. E., et al.\ 2014, , 444, 3230. doi:10.1093/mnras/stu1651

    2014 doi

  9. [17]

    S., & Brett, J

    Bessell, M. S., & Brett, J. M.\ 1988, , 100, 1134

    1988

  10. [18]

    A., Vine, S

    Bonnell, I. A., Vine, S. G., & Bate, M. R.\ 2004, , 349, 735. doi:10.1111/j.1365-2966.2004.07543.x

    2004

  11. [19]

    Brand J., Blitz L., 1993, , 275, 67

    1993

  12. [20]

    M., Petrov, A

    Bykov, A. M., Petrov, A. E., Ponomaryov, G. A., 2024, DOI: 10.48550/arXiv.2401.06271

    2024 doi arXiv

  13. [21]

    doi:10.1051/0004-6361/202038192

    Cantat-Gaudin, T., Anders, F., Castro-Ginard, A., et al.\ 2020, , 640, A1. doi:10.1051/0004-6361/202038192

    2020 doi

  14. [22]

    & Anders, F.\ 2020, , 633, A99

    Cantat-Gaudin, T. & Anders, F.\ 2020, , 633, A99. doi:10.1051/0004-6361/201936691

    2020 doi

  15. [23]

    Cantat-Gaudin, T.\ 2018, , 618, A93

    2018

  16. [24]

    Cao, Z., et al.\ 2024, , 271,25

    2024

  17. [25]

    Cao, Z., et al.\ 2023, Annu. Rev. Nucl., 73, 341

    2023

  18. [26]

    Cao, Z., et al.\ 2021a, Nature, 594, 33

  19. [27]

    Cao, Z., et al.\ 2021b, , 919, L22

  20. [28]

    & Giuliani, A., Appl

    Cardillo, M. & Giuliani, A., Appl. Sci. 2023, 13(11), 6433

    2023

  21. [29]

    Cristofari, P.\ 2021, Universe, 7, id.324

    2021

  22. [30]

    F., Povich, M

    Churchwell, E., Watson, D. F., Povich, M. S., Taylor, M. G.\ 2007, , 670, 428

    2007

  23. [31]

    de la Fuente, E., et al.\ 2023a, The PeVatrons and the HAWC Observatory in Mexico, arXiv, arXiv:2306.06293

    arXiv

  24. [32]

    2023b, , 75, 546

    de la Fuente, E, Toledano--Ju\'arez, I., Kawata, K., et al. 2023b, , 75, 546

  25. [33]

    2023c, , 275, L5

    de la Fuente, E, Toledano--Ju\'arez, I., Kawata, K., et al. 2023c, , 275, L5

  26. [34]

    A., Kurtz, S

    de la Fuente, E., Porras, A., Trinidad, M. A., Kurtz, S. E.\ 2020a, , 492, 895

  27. [35]

    A., Porras, A.\ 2020b, , 497, 4436

    de la Fuente, E., Tafoya, D., Trinidad, M. A., Porras, A.\ 2020b, , 497, 4436

  28. [36]

    de la Fuente, E., Porras, A., Grave, J. M. C., et al.\ 2009, in A Long Walk Through Astronomy: A Celebration of Luis Carrasco's 60th Birthday, E. Recillas, A. Luna, & Y. D. Mayya editors, Revista Mexicana de Astronomía y Astrofísica (Serie de Conferencias), 37, 13

    2009

  29. [37]

    M., Hartmann, D., & Thaddeus, P.\ 2001, , 547, 792

    Dame, T. M., Hartmann, D., & Thaddeus, P.\ 2001, , 547, 792

    2001

  30. [38]

    D., 1986, , 157, 223

    Dermer C. D., 1986, , 157, 223

    1986

  31. [39]

    & Majumdar

    De Sarkar, A. & Majumdar. P.\ 2024, , 681, 34

    2024

  32. [40]

    De Sarkar, A.\ 2023, , 521, L5

    2023

  33. [41]

    Dobashi, K., Shimoikura, T., Endo, N., Takagi, C., et al.\ 2018, , 71, S11

    2018

  34. [42]

    Dobashi, K., Matsumoto, T., Shimoikura, T., Saito, H., et al.\ 2014, , 797, 58

    2014

  35. [43]

    Dobashi, K., Bernard, J.-Ph., Yonekura, Y., & Fukui, Y., 2014, , 95, 419

    2014

  36. [44]

    N., Floer, L., et al

    Bekhti, B. N., Floer, L., et al. 2016, , 594, A116

    2016

  37. [45]

    M.\ 1978, , 38, 309

    Humphreys, R. M.\ 1978, , 38, 309

    1978

  38. [46]

    R., Choi M., & Kang M., 2017, , 845, 21

    Kang S.-J., Kerton C. R., Choi M., & Kang M., 2017, , 845, 21

    2017

  39. [47]

    & Gupta, N.\ 2022, , 926, 110

    Kar, A. & Gupta, N.\ 2022, , 926, 110

    2022

  40. [48]

    R., Aharonian, F

    Kelner, S. R., Aharonian, F. A., & Bugayov, V. V., 2006, Phys. Rev. D, 74, 034018, doi:10.1103/PhysRevD.74.034018

    2006 doi

  41. [49]

    doi:10.1086/108756

    King, I.\ 1962, , 67, 471. doi:10.1086/108756

    1962 doi

  42. [50]

    Knodlseder, J.\ 2000, , 360, 539

    2000

  43. [51]

    V., Piskunov, A

    Kharchenko, N. V., Piskunov, A. E., Schilbach, E., et al.\ 2013, , 558, A53. doi:10.1051/0004-6361/201322302

    2013 doi

  44. [52]

    V.\ 2012, , 543, A156

    Kharchenko, N. V.\ 2012, , 543, A156

    2012

  45. [53]

    T., 2014, , 791, 131

    Koenig X.-P., & Leizawitz D. T., 2014, , 791, 131

    2014

  46. [54]

    Kronberger, M., Teutsch, P., Alessi, B., et al.\ 2006, , 447, 921

    2006

  47. [55]

    1983, , 128, 84

    Koornneef J. 1983, , 128, 84

    1983

  48. [56]

    C.\ 1992, , 393, 278

    Lada, C.J., & Adams, F. C.\ 1992, , 393, 278

    1992

  49. [57]

    Bull., 69, 499

    LHAASO Coll.\ 2024, Sci. Bull., 69, 499

    2024

  50. [58]

    Phys., 120, 102441

    Lipari, P., & Vernetto, S.\ 2020, Astropart. Phys., 120, 102441

    2020

  51. [59]

    A., Pravdikova, V

    Lozinskaya, T. A., Pravdikova, V. V., and Finoguenov, A. V.\ 2002, Astron. Lett. 28, 223-236

    2002

  52. [60]

    C, 46, 030001

    Ma, X-H., et al.\ 2022, Chinese Phys. C, 46, 030001

    2022

  53. [61]

    doi:10.3847/1538-4357/835/1/77

    Marigo, P., Girardi, L., Bressan, A., et al.\ 2017, , 835, 77. doi:10.3847/1538-4357/835/1/77

    2017 doi

  54. [62]

    Matsumoto, T., & Hanawa, T.\ 2011, , 728, 47

    2011

  55. [63]

    Mitchell, A. M. W.\ 2024, , 684, A66

    2024

  56. [64]

    J.\ 2017, , 834, 57

    Miville-Deschenes, M.-A., Murray, N., & Lee, E. J.\ 2017, , 834, 57

    2017

  57. [65]

    A., Baume, G., & Gamen, R.\ 2019, , 488, 2158

    Molina Lera, J. A., Baume, G., & Gamen, R.\ 2019, , 488, 2158. doi:10.1093/mnras/stz1710

    2019 doi

  58. [66]

    doi:10.1051/0004-6361/202039837

    Moscadelli, L., Beuther, H., Ahmadi, A., et al.\ 2021, , 647, A114. doi:10.1051/0004-6361/202039837

    2021 doi

  59. [67]

    R., Calvet, N., & Hillenbrand, L

    Meyer, M. R., Calvet, N., & Hillenbrand, L. A.\ 1997, , 114, 288

    1997

  60. [68]

    Ohm, S., et al.\ 2023, Nucl. Instrum. Methods Phys. Res. A, 1055, 168442

    2023

  61. [69]

    R., Kinwah W., Yoshiyuki, et al.\ 2023, Galaxies, 11, 86

    Owen, E. R., Kinwah W., Yoshiyuki, et al.\ 2023, Galaxies, 11, 86

    2023

  62. [70]

    & Aharonian, F.\ 2022, , 659, A57

    Peron, G. & Aharonian, F.\ 2022, , 659, A57

    2022

  63. [71]

    Prusti, T., de Bruijne, J.H.J., et al.\ 2016, , 595, A1

    2016

  64. [72]

    J., Menten, K

    Reid, M. J., Menten, K. M., Brunthaler, A., et al.\ 2019, , 885, 131. doi:10.3847/1538-4357/ab4a11

    2019 doi

  65. [73]

    J., & Zheng, X--W, 2020, Sci

    Reid, M. J., & Zheng, X--W, 2020, Sci. Am., 322, 28

    2020

  66. [74]

    I Astronomical Society of the Pacific, ed

    Reipurth B., & Schnider, N.\ 2008, in Handbook of Star Forming Regions Vol. I Astronomical Society of the Pacific, ed. Bo Reipurth , Nicola Schneider, 1--54

    2008

  67. [75]

    H., & Lebofsky M

    Rieke G. H., & Lebofsky M. J. 1985, , 288, 618

    1985

  68. [76]

    Schneider, N., et al.\ 2006, , 458, 855

    2006

  69. [77]

    Schmidt--Kaler, Th.\ 1982, BICDS, 23, 2

    1982

  70. [78]

    Shimoikura, T., Dobashi, K., Matsumoto, T., Hirota, T., 2018, , 855, 45

    2018

  71. [79]

    Skrutskie, M. F. et al.\ 2006, , 131, 1163

    2006

  72. [80]

    R., et al.\ 2003, , 125, 3145

    Taylor, A. R., et al.\ 2003, , 125, 3145

    2003

  73. [81]

    Vallenari, A., Brown, A. G. A., et al.\ 2023, , 674, A1

    2023

  74. [82]

    Gaia Collaboration, Vallenari, A., Brown, A. G. A., et al.\ 2023, , 674, A1. doi:10.1051/0004-6361/202243940

    2023 doi

  75. [83]

    L., et al.\ 2010, , 140, 1868

    Wright, E. L., et al.\ 2010, , 140, 1868

    2010

Pith tools

Reviewed August 16, 2026 · model on record in the stance chip above.