Pith. sign in

REVIEW 3 major objections 4 minor 50 references

Neutral iron line in the supernova remnant IC 443 and implications for MeV cosmic rays

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

Challenge this review Re-run · record.json Download PDF Read on arXiv ↗ Review JSON

Pith's one-line read Two blob-like 6.4 keV Fe I K-alpha enhancements in IC 443 are attributed to MeV protons accelerated at the SNR shock and leaking into molecular clouds, with intensities matching a model that also produces GeV-TeV protons.

desk verdict A genuinely new Fe K-alpha map of IC 443 with a plausible LECR origin, but the quantitative agreement with the escape model is weaker than the abstract claims. read the letter →

arxiv 1908.05119 v1 pith:LVVSKM66 submitted 2019-08-14 astro-ph.HE

Kumiko K. Nobukawa , Arisa Hirayama , Aika Shimaguchi , Yutaka Fujita , Masayoshi Nobukawa , Shigeo Yamauchi This is my paper · ORCID
classification astro-ph.HE
keywords supernovaremnantsIC443FeIK-alphalinelow-energycosmicraysMeVprotonsmolecularcloudsX-rayspectroscopycosmic-rayacceleration
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 reports the discovery of two bright blob-like enhancements of the 6.4 keV Fe I K-$\alpha$ line in the supernova remnant IC 443, one in the northwest and one near the middle, both coinciding with molecular clouds that the remnant's shock is interacting with. The paper argues that the most plausible origin is inner-shell ionization of neutral iron by MeV protons accelerated at the SNR shock and then leaking into the molecular clouds, rather than emission from hot plasma or X-ray irradiation by the nearby pulsar wind nebula. The measured line intensities, $0.273 \pm 0.119$ and $0.344 \pm 0.277$ photons s$^{-1}$ cm$^{-2}$ sr$^{-1}$, agree with the intensity of $0.29^{+0.10}_{-0.11}$ photons s$^{-1}$ cm$^{-2}$ sr$^{-1}$ predicted by a cosmic-ray escape model when the accelerated proton spectrum is fixed by the GeV-TeV gamma-ray observations. If the interpretation is right, IC 443 co-accelerates MeV protons with the GeV and TeV protons whose pion-decay gamma-rays are already observed, providing a direct observational bridge between low-energy and high-energy cosmic-ray acceleration in supernova remnants.

What carries the argument

The mechanism that carries the argument is inner-shell ionization of neutral iron: a MeV proton knocks out a K-shell electron from Fe, and the resulting vacancy is filled by an electron that emits the Fe I K-alpha photon at 6.4 keV. The paper separates proton bombardment from electron bombardment by the line's equivalent width, and it anchors the proton flux by fitting a cosmic-ray escape model to the observed gamma-ray spectrum. In that model, the momentum at which protons escape the SNR decreases as the shock expands, producing a break in the proton spectrum and hence a bend in the gamma-ray spectrum near ~1 GeV; the same model then predicts the 6.4 keV line intensity, and the measured value matches the prediction to within the quoted uncertainties.

What would settle it

Measure the spatial profile of the 6.4 keV line across Reg 2 with a higher-resolution X-ray instrument: if the escape model is right, the line brightness should decline at roughly the ionization-cooling distance of ~10 MeV protons (about 500 yr of travel at $n_H=730$ cm$^{-3}$), and the line should not extend smoothly far beyond the 4-arcmin blob; a detection of 6.4 keV emission substantially more extended than that, or a centroid that shifts with position toward the pulsar wind nebula, would require X-ray irradiation or a very different diffusion environment.

Watch

Extended reading notes

Core claim

The paper's central claim is that the Fe I K-$\alpha$ line in IC 443, enhanced in two blob-like regions where the supernova remnant meets molecular clouds, is produced by low-energy cosmic-ray protons in the MeV band. Neutral iron atoms in the clouds are inner-shell ionized by these protons and emit at 6.4 keV; the large equivalent widths, >1.2 keV in Reg 1 and 0.7$^{+0.9}_{-0.6}$ keV in Reg 2, match the proton-bombardment expectation rather than the 0.2--0.4 keV expected for electron bombardment. The authors rule out X-ray irradiation from the pulsar wind nebula 1SAX J0617.1+2221 because the required flux would be two orders of magnitude above its observed flux. Applying a cosmic-ray escape model in which the same shock accelerates protons across energies, with the proton spectrum fixed by GeV and very-high-energy gamma-ray data, predicts a line intensity of $0.29^{+0.10}_{-0.11}$ photons s$^{-1}$ cm$^{-2}$ sr$^{-1}$, consistent with both measured regions; no significant line is found in a third region used as reference.

Load-bearing premise

The load-bearing premise is that enough ~10 MeV protons can travel from the shock into the molecular clouds and spread over the observed 4-arcmin region before they lose energy by ionizing gas, and the paper's own diffusion estimate falls short of this requirement by about a factor of 40, with the gap handled by invoking unmodelled cloud geometry or extended injection.

Editorial extensions

If this is right

  • MeV cosmic-ray protons are accelerated together with GeV and TeV protons at the IC 443 shock, meaning the same acceleration mechanism populates the low-energy cosmic rays that ionize interstellar gas.
  • Fe I K-alpha line imaging around molecular-cloud-interacting SNRs can act as a spatial probe of sub-GeV cosmic-ray escape, complementing gamma-ray and H3+ ionization-rate measurements.
  • The gamma-ray spectrum of IC 443 requires a smaller diffusion coefficient than those inferred for W28 and W44, so middle-aged SNRs may differ in how they release low-energy cosmic rays.
  • Because Reg 2 coincides with a dense molecular core and a gamma-ray clump, the data place escaping low-energy and high-energy cosmic rays in the same clouds, allowing a joint test of escape models.

Reading between the lines

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

  • A testable extension is to map the 6.4 keV line at higher angular resolution: if the escape model is right, the line should trace the shock-cloud contact surface and fade within the roughly 500-yr ionization-cooling distance of 10 MeV protons, whereas a smoother or more extended profile would point to a larger diffusion coefficient inside the cloud than the model assumes.
  • The roughly 40-fold gap between the diffusion coefficient needed to explain the 4-arcmin size of Reg 2 and the coefficient used in the model could be resolved if future instruments detect a brightness gradient across the line-emitting cloud; such a gradient would measure the effective diffusion coefficient in the molecular-cloud environment.
  • The same method could be applied to other supernova remnants with both gamma-ray spectra and Fe I K-alpha detections to test whether co-acceleration of MeV and GeV-TeV protons is generic or peculiar to IC 443-like remnants.
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 reports Suzaku XIS observations of IC 443 and constructs an Fe I K-alpha line intensity map. It identifies two blob-like enhancements, Reg 1 in the northwest and Reg 2 in the middle of the remnant, both associated with molecular clouds. Spectral fits yield line intensities of 0.273 +/- 0.119 and 0.344 +/- 0.277 photons s^-1 cm^-2 sr^-1 for Regs 1 and 2, with large equivalent widths. The authors argue that the line is produced by inner-shell ionization of neutral Fe by MeV protons leaking from the SNR shock into adjacent molecular clouds, and they compare the observed intensity with a prediction from a CR escape model fitted to gamma-ray data. They find consistency (predicted 0.29(+0.10/-0.11)) and conclude that MeV protons are accelerated together with GeV-TeV protons in the SNR.

Significance. If the detection and the quantitative comparison were robust, this paper would provide a rare direct probe of the long-missing MeV cosmic-ray population in an SNR, with implications for the co-acceleration of low- and high-energy protons. The analysis uses an observable (Fe I K-alpha line) that is independent of the gamma-ray data used to fit the CR model, which is a genuine strength, and the model is described in enough detail to be checked. The main caveats are the marginal significance of one of the two regions, the lack of a trials correction for source selection, and an admitted factor-of-40 discrepancy in the diffusion coefficient needed to explain the spatial extent of Reg 2. These issues do not refute the scenario but they currently prevent the paper from making a strong quantitative case for the escape model as fitted.

major comments (3)
  1. [Appendix, Eq. (A2) and following paragraph; Section 4.2]
  2. [Sections 3.1 and 3.2, Table 2]
  3. [Section 4.2 and Appendix]
minor comments (4)
  1. [Section 4.1]
  2. [Section 4.2]
  3. [Section 3.2]
  4. [Figure 1 and Appendix]

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity: Fe I line prediction follows from gamma-ray-fitted escape model, with the line data used only as a posterior check.

full rationale

I walked the derivation chain. The Fe I K-alpha intensities in Regs 1 and 2 (Table 2: 0.273 +/- 0.119 and 0.344 +/- 0.277 photons s^-1 cm^-2 sr^-1) are measured from Suzaku spectra and are never used as fitting inputs to the CR escaping model. In the Appendix, the model parameters ECR,tot, s, pmax, chi, and delta are fitted exclusively to the Fermi, VERITAS, MAGIC, and AGILE gamma-ray spectra, after which the paper states: 'we calculate the Fe I K-alpha line intensity and find that it should be 0.29+0.10-0.11 photons s^-1 cm^-2 sr^-1.' Thus the line prediction is a forward calculation from a CR population constrained by gamma rays, not a renaming or refitting of the line flux. The Makino et al. (2019) model is applied rather than being the target result; it was developed for W28 and W44 and is externally falsifiable, so sharing authors does not make the citation circular. The admitted factor-40 mismatch between the diffusion coefficient required for Reg 2's 4-arcmin extent (D' >= 4e26 cm^2/s) and D(10 MeV) = 9e24 cm^2/s from equation (A2) is a quantitative consistency problem, but it is not circularity: it does not reduce the predicted line intensity to an observed line input. The observed-to-predicted comparison remains a genuine cross-check, so the circularity score is 0.

Assumptions & free parameters 11 free parameters · 6 assumptions · 0 invented entities

The central claim rests on a chain of assumptions: the spectral decomposition of the Suzaku data, the exclusion of PWN and plasma origins, and the CR escape model, which carries five fitted parameters plus several geometric inputs from private-communication CO data. The Fe I line prediction is not circular because the line is not used to fit the model, but it inherits the full uncertainty of the gamma-ray fit and the assumed MC density and geometry.

free parameters (11)
  • ECR_tot = 3.1e50 erg (+0.5/-0.5)
    Total CR energy fitted to the gamma-ray spectrum in the Appendix; sets the normalization of the CR spectrum and directly scales the predicted Fe I K-alpha intensity.
  • s = 2.52 (+0.10/-0.20)
    Index of the CR momentum spectrum at the shock, fitted to gamma rays; controls the relative number of MeV protons and hence the Fe I line yield.
  • pmax c = 4.0e13 eV (+3.9/-2.0)
    Maximum CR momentum at the start of the Sedov phase, fitted to gamma rays; sets the escape momentum evolution via equation (A1).
  • chi = 0.011 (+0.003/-0.002)
    Diffusion suppression factor fitted to the convex GeV-TeV gamma-ray shape; much smaller than the 0.5 used for W28 and W44 in Makino et al. (2019), and controls how closely low-energy CRs stay to the shock.
  • delta = 0.58 (+0.07/-0.08)
    Energy dependence index of the diffusion coefficient, fitted to gamma rays; sets the energy-dependent escape and the location of the external spectral break.
  • nH = 730 cm^-3
    Molecular cloud density assumed from NANTEN2 CO data via private communication; enters linearly in the predicted Fe I K-alpha intensity and in the 10 MeV proton cooling time.
  • fgas = 0.05
    Volume filling factor of the MC shell, assumed from private CO data; sets the MC mass and the gamma-ray and Fe I line emissivities.
  • L1, L2 = 12 pc, 15 pc
    Inner and outer radii of the MC shell, assumed from CO observations; define the volume and mass of target gas for both gamma-ray and Fe I line production.
  • tobs = 1.5e4 yr
    Assumed present age of IC 443 in the Sedov evolution; determines the escape momentum p_esc(tobs) and the current stage of CR release.
  • RSedov, tSedov, alpha = 2.1 pc, 210 yr, 6.5
    Sedov-phase parameters carried over from Makino et al. (2019); set the momentum of escaping CRs at the present time through equation (A1).
  • Distance to IC 443 = 1.5 kpc
    Assumed from Welsh & Sallmen (2003); converts angular sizes to physical sizes and sets the SNR/MC geometry used in the model.
assumptions (6)
  • domain assumption The SNR evolves in the Sedov phase with the same parameters as assumed for W28 and W44 (RSedov=2.1 pc, tSedov=210 yr, alpha=6.5).
    Invoked in the Appendix to compute the escape momentum p_esc(tobs); not independently verified for IC 443.
  • domain assumption CRs with momenta above p_esc(t) have gradually escaped, and when the shock contacts MCs at t~tobs the confinement of lower-momentum CRs is broken so they escape together.
    This is the escape model from Makino et al. (2019); it is the physical scenario that connects MeV protons to the molecular clouds.
  • domain assumption The MCs form a shell between 12 and 15 pc with density 730 cm^-3 and filling factor 0.05, based on private-communication CO data.
    The predicted Fe I K-alpha intensity scales linearly with these values; the CO data are not publicly cited.
  • domain assumption The gamma-ray spectra from Fermi, VERITAS, MAGIC, and AGILE trace the hadronic CR proton population in the same molecular clouds.
    The model fit to gamma rays assumes a hadronic origin and that these gamma rays come from protons interacting with the same MC gas that produces the Fe I line.
  • domain assumption Atomic cross-sections for Fe K-shell ionization by protons are taken from Tatischeff et al. (2012), with peak response near 10 MeV.
    This is external atomic data needed to convert the CR flux into a Fe I K-alpha line intensity.
  • domain assumption The hard-band spectral decomposition relies on fixed parameters (kTe=0.6 keV, photon index Gamma=2.5, CXB from Kushino et al. 2002) adopted from prior studies.
    These values cannot be constrained in the 4-10 keV band; if the true continuum differs, the measured Fe I line intensity could shift.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Neutral iron line in the supernova remnant IC 443 and implications for MeV cosmic rays." pith.science (2026). https://pith.science/paper/LVVSKM66

@misc{pith2026190805119,
  author       = {Pith},
  title        = {Pith review of: Neutral iron line in the supernova remnant IC 443 and implications for MeV cosmic rays},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/LVVSKM66}},
  note         = {Machine review of arXiv:1908.05119}
}
abstract

We report a discovery of bright blob-like enhancements of an Fe I K$\alpha$ line in the northwest and the middle of the supernova remnant (SNR) IC 443. The distribution of the line emission is associated with molecular clouds interacting with the shock front, and is totally different from that of the plasma. The Fe I K$\alpha$ line has a large equivalent width. The most plausible scenario for the origin of the line emission is that the MeV protons accelerated in the shell leak into the molecular clouds and ionize the Fe atoms therein. The observed Fe I K$\alpha$ line intensity is consistent with the prediction of a theoretical model, in which MeV protons are accelerated along with GeV and TeV protons at the SNR.

Figures

Figures reproduced from arXiv: 1908.05119 by the authors.

Figure 1
Figure 1. Left panel: intensity profile of Fe I Kα line. Color scale is in linear. Vignetting is corrected. The regions surrounded by white lines show the FOVs of the XIS. The dotted white line represents the approximate shape of the radio shell (Lee et al. 2008). Point sources and the PWN 1SAX J0617.1+2221, which are marked with the solid white circles and the ellipse regions, respectively, are excluded from the image (see s… view at source ↗
Figure 2
Figure 2. X-ray spectra extracted from Reg 1 (a), Reg 2 (b) and Reg 3 (c) and the best-fit models. The solid red, blue, and orange lines are bremsstrahlung, power-law component (power law plus the Fe I Kα line), Fe XXV and Fe XXVI Kα lines, respectively. The gray lines indicates the CXB. The green lines in Reg 2 and Reg 3 shows the contamination flux from 1SAX J0617.1+2221. 6 [PITH_FULL_IMAGE:figures/full_fig_p006_2.png] view at source ↗
Figure 3
Figure 3. Comparison of the best-fit model (solid line) with Fermi (green filled circles; Ackermann et al. 2013), VERITAS (black open squares; Acciari et al. 2009), MAGIC (red crosses; Albert et al. 2007), and AGILE (purple open triangles; Tavani et al. 2010) observations for the SNR IC 443. and 2, respectively (section 3.2). The scenario that can explain both the regions is MeV-proton bombardment. 4.2 Comparison with Gamma-r… view at source ↗
Figures from the paper (1 more)
Figure 3
Figure 3. Figure 3: figure 3. From the results, we also obtain [PITH_FULL_IMAGE:figures/full_fig_p010_3.png]

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

50 extracted references · 45 canonical work pages

  1. [1]

    A., et al

    Abdo, A. A., et al. 2009, ApJS, 183, 46

    work page 2009

  2. [2]

    A., et al

    Abdo, A. A., et al. 2010, ApJ, 712, 459

    work page 2010

  3. [3]

    A., et al

    Acciari, V. A., et al. 2009, ApJ, 698, L133

    work page 2009

  4. [4]

    \ 2013, Science, 339, 807

    Ackermann, M., et al. \ 2013, Science, 339, 807

    work page 2013

  5. [5]

    2007, ApJ, 664, L87

    Albert, J., et al. 2007, ApJ, 664, L87

    work page 2007

  6. [6]

    M., Aharonian, F

    Atoyan, A. M., Aharonian, F. A., & V \"o lk, H. J.\ 1995, , 52, 3265

    work page 1995

  7. [7]

    Bamba, A. et al. 2018, ApJ, 854, 71

    work page 2018

  8. [8]

    Bocchino, F., & Bykov, A. M. 2001, A&A, 376, 248

    work page 2001

Show all 50 references
  1. [9]

    Bocchino, F., & Bykov, A. M. 2003, A&A, 400, 203

    2003

  2. [10]

    H., Chin, G., & Knapp, G

    Cornett, R. H., Chin, G., & Knapp, G. R. 1977, A&A, 54, 889

    1977

  3. [11]

    C., et al

    Cummings, A. C., et al. 2016, ApJ, 831, 18

    2016

  4. [12]

    2011 PASJ, 63, 535

    Dogiel, V., Chernyshov, D., Koyama, K., Nobukawa, M., & Cheng, K -S. 2011 PASJ, 63, 535

    2011

  5. [13]

    J., & Takahara, F

    Fujita, Y., Ohira, Y., Tanaka, S. J., & Takahara, F. 2009, ApJL, 707, L179

    2009

  6. [14]

    2010, ApJL, 712, L153

    Fujita, Y., Ohira, Y., & Takahara, F. 2010, ApJL, 712, L153

    2010

  7. [15]

    2011, MNRAS, 415, 3434

    Fujita, Y., Takahara, F., Ohira, Y., & Iwasaki, K. 2011, MNRAS, 415, 3434

    2011

  8. [16]

    2018, A&A, 615, A157

    Greco, E., Miceli, M., Orlando, S., Peres, G., Troja, E., & Bocchino, F. 2018, A&A, 615, A157

    2018

  9. [17]

    H. E. S. S. collaboration, 2018, A&A, 612, A1

    2018

  10. [18]

    K., Nobukawa, & M., Koyama, K., PASJ, 71, 37

    Hirayama, A., Yamauchi, S., Nobukawa, K. K., Nobukawa, & M., Koyama, K., PASJ, 71, 37

  11. [19]

    Indriolo, N. et al. 2010, ApJ, 724, 1357

    2010

  12. [20]

    Indriolo, N., & McCall, B. J. 2012, ApJ, 745, 91

    2012

  13. [21]

    \ 2007, PASJ, 59, S113

    Ishisaki, Y., et al. \ 2007, PASJ, 59, S113

    2007

  14. [22]

    2010, ApJ, 712, 1147

    Jiang, B., Chen, Y., Wang, J., Su, Y., Zhou, X., Safi-Harb, S., & DeLaney, T. 2010, ApJ, 712, 1147

    2010

  15. [23]

    S., & Mewe, R

    Kaastra, J. S., & Mewe, R. 1993, A&A, 97, 443

    1993

  16. [24]

    \ 2007, PASJ, 59, S23

    Koyama, K., et al. \ 2007, PASJ, 59, S23

    2007

  17. [25]

    \ 2002, PASJ, 54, 327

    Kushino, A., et al. \ 2002, PASJ, 54, 327

    2002

  18. [26]

    J., Koo, B

    Lee, J. J., Koo, B. C., Yun, M. S., Stanimirovi\'c, S., Heiles, C., & Heyer, M. 2008, AJ, 135, 796

    2008

  19. [27]

    K., Matsumoto, & H., Ohira, Y

    Makino, K., Fujita, Y., Nobukawa, K. K., Matsumoto, & H., Ohira, Y. 2019, PASJ accepted

    2019

  20. [28]

    1994, A&A, 286, 983

    Mannheim, K., & Schlickeiser, R. 1994, A&A, 286, 983

    1994

  21. [29]

    Matsumura, H., Tanaka, T., Uchida, H., Okon, H., & Tsuru, T. G. 2017, ApJ, 851, 73

    2017

  22. [30]

    K., et al

    Nobukawa, K. K., et al. 2018, ApJ, 854, 87

    2018

  23. [31]

    Ohira, Y., Murase, K., & Yamazaki, R.\ 2011, , 410, 1577

    2011

  24. [32]

    Ohnishi, T., et al.\ 2014, , 784, 74

    2014

  25. [33]

    M., Clearfield, C

    Olbert, C. M., Clearfield, C. R., Williams, N. E., Keohane. J. W., & Frail. D. A. 2001, ApJ, 554, L205

    2001

  26. [34]

    E., Seward, F

    Petre, R., Szymkowiak, A. E., Seward, F. D., & Willingale R. 1988, ApJ, 335, 215 56, 3614

    1988

  27. [35]

    K., Uchiyama, H., Yamauchi, S., & Koyama, K

    Saji, S., Matsumoto, H., Nobukawa, M., Nobukawa, K. K., Uchiyama, H., Yamauchi, S., & Koyama, K. 2018, PASJ, 70, 23

    2018

  28. [36]

    Saji, S., Doctoral dissertation, Nagoya University, 2018

    2018

  29. [37]

    2015, Revolution in Astronomy with ALMA: The Third Year, ed

    Sano, H., et al. 2015, Revolution in Astronomy with ALMA: The Third Year, ed. Daisuke Iono, Ken’ichi Tatematsu, Al Wootten, & Leonardo Testi, ASP Conference Series, 499

    2015

  30. [38]

    2014, PASJ, 66, 124

    Sato, T., Koyama, K., Takahashi, T., Odaka, H., & Nakashima, S. 2014, PASJ, 66, 124

    2014

  31. [39]

    J., et al

    Serlemitsos, P. J., et al. \ 2007, PASJ, 59, S9

    2007

  32. [40]

    K., Brickhouse, N

    Smith, R. K., Brickhouse, N. S., Liedahl, D. A., & Raymond, J. C. 2001, ApJL, 556, L91

    2001

  33. [41]

    W., & Moskalenko, I

    Strong, A. W., & Moskalenko, I. V. 1998, ApJ, 509, 212

    1998

  34. [42]

    2012, A&A, 546, A88

    Tatischeff, V., Decourchelle, A., &Maurin, G. 2012, A&A, 546, A88

    2012

  35. [43]

    Tavani, M., et al.\ 2010, , 710, L151

    2010

  36. [44]

    \ 2008, PASJ, 60, S11

    Tawa, N., et al. \ 2008, PASJ, 60, S11

    2008

  37. [45]

    2006, ApJ, 649, 258

    Troja, E., Bocchino, & Reale, F. 2006, ApJ, 649, 258

    2006

  38. [46]

    2008, A&A, 485, 777

    Troja, E., Bocchino, F., Miceli, M., & Reale, F. 2008, A&A, 485, 777

    2008

  39. [47]

    S., Ozaki, M., & Yonetoku, D

    Yamaguchi, H., Ozawa, M., Koyama, K., Masai, K., Hiraga, J. S., Ozaki, M., & Yonetoku, D. 2009, ApJL, 705, L6

    2009

  40. [48]

    2014, ApJL, 785, L27

    Yamaguchi, H., et al. 2014, ApJL, 785, L27

    2014

  41. [49]

    Y., & Sallmen, S

    Welsh, B. Y., & Sallmen, S. 2003, A&A, 408, 545

    2003

  42. [50]

    Computer Modern (defalt font)

    \@bibitem \@bib@author\@prev@author \@set@biblabel \@lbibitem[#1] \@bib@parse#1()\@nil \@set@biblabel \@bib@parse#1(#2)#3\@nil \@bib@author #1 @edef\@bib@year @space#2 \@empty \@set@biblabel#1 \@bib@author\@empty \@latex@warning Author name should be given for reference entry ...

Pith tools

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