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A pioneering experiment combining single-antenna and aperture-synthesis data to measure Faraday rotation with GMIMS and the CGPS

T0 review · 4 major / 5 minor · reviewed 2026-08-10 · deepseek-v4-flash

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Pith's one-line read The paper produces the first full-scale diffuse Galactic Faraday rotation maps, combining single-antenna GMIMS-HBN and aperture-synthesis CGPS polarization data to reach 3-arcmin resolution across all spatial scales.

desk verdict Genuinely new full-scale diffuse RM maps, honestly limited; send to a serious referee, and push on the beam-model validation and the abstract's wording. read the letter →

arxiv 2501.10623 v2 pith:E3N42HYS submitted 2025-01-18 astro-ph.GA astro-ph.IM

Anna Ordog , Jo-Anne C. Brown , T. L. Landecker , Alex S. Hill , Roland Kothes , Jennifer L. West , John M. Dickey , Marijke Haverkorn
show 6 more authors
Ettore Carretti Alec J. M. Thomson Andrea Bracco D. A. Del Rizzo Ryan R. Ransom Robert I. Reid
This is my paper · ORCID
classification astro-ph.GAastro-ph.IM
keywords FaradayrotationmeasurediffuseGalacticsynchrotronemissionpolarizationsingle-antennaplusinterferometryuv-planefeatheringmagneticfieldGMIMS-HBNandCGPS
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 first experiment to combine single-antenna and aperture-synthesis polarization data over multiple frequency channels, producing diffuse Galactic synchrotron Faraday rotation maps that cover all spatial scales down to 3 arcmin. The authors merge GMIMS-HBN single-dish Stokes Q and U maps with CGPS aperture-synthesis data in four frequency bands, feathering the two datasets in the uv-plane and fitting per-pixel rotation measures to polarization angle versus $\lambda^2$. The point of the experiment is to show that smooth, large-scale polarized emission, which interferometers filter out, can be recovered by adding single-antenna data, while the interferometer supplies arcminute detail. The resulting RM maps reveal both large-scale magnetic-field structures and small-scale RM variability, and demonstrate that useful diffuse-emission rotation measures can be extracted even from the narrow 35 MHz CGPS bandwidth, with the caveat that the RM values are sensitive to Faraday complexity.

What carries the argument

The central mechanism is feathering in the uv-plane: after Fourier transforming both datasets, the GMIMS-HBN visibilities are deconvolved by the single-antenna beam transform and low-pass filtered, then combined with the CGPS aperture-synthesis visibilities through complementary cubic weighting functions over the baseline range 8.572-17.144 m. This produces combined Stokes Q and U maps that keep sensitivity from the largest spatial scales down to the 3 arcmin resolution of the convolved maps; the per-pixel rotation measure is then obtained from a linear fit to polarization angle versus $\lambda^2$ across the four 7.5 MHz channels.

What would settle it

Compare the full-scale per-pixel RMs against the peak Faraday depth of the full-band GMIMS-HBN RM-synthesis cube at the same lines of sight: a systematic offset or sign disagreement beyond the stated uncertainties would show that the 35 MHz linear-fit RMs are not tracing the same magnetoionic structure. A second check is to recompute the RMs after perturbing the feathering boundaries, for example from 7 m to 20 m, and see whether the large-scale RM structures shift by more than the quoted errors.

Watch

Extended reading notes

Core claim

The central claim is that diffuse Galactic synchrotron emission can be mapped in Faraday rotation across all spatial scales down to 3 arcmin resolution for the first time, by combining GMIMS-HBN single-antenna and CGPS aperture-synthesis Stokes Q and U data after spatial filtering. The combination is carried out by deconvolving the single-antenna beam (modeled as a Gaussian with 9 m HWHM in the uv-plane), low-pass filtering the single-antenna visibilities at 18 m, and feathering with the aperture-synthesis visibilities using complementary cubic weights over baselines from 8.572 m to 17.144 m. Each of the four CGPS frequency channels receives a matching GMIMS-HBN band, and a linear fit of polarization angle versus $\lambda^2$ gives an RM per pixel. A mock-observation simulation indicates that the missing intermediate uv spacings introduce only about 6% error in Stokes U away from bright sources, which the authors argue is adequate for a prototype demonstration. They show regions such as Sh2-216, IC 443, and the $\ell = 173^\circ$ H II complex where adding the single-antenna component changes the RM sign or reveals coherent structures invisible to aperture synthesis alone.

Load-bearing premise

The load-bearing premise is that the beam-deconvolved GMIMS-HBN visibilities faithfully represent the true large-scale polarized sky and that the feathering weights bridge the missing 8.6-17 m baselines without bias, since the only simulation validating this stitch excludes the bright-source regions that contaminate the real data.

Editorial extensions

If this is right

  • Galactic magnetic-field studies can now use diffuse-emission rotation measures at arcminute resolution rather than relying only on sparse compact-source RMs or single-antenna-only beams.
  • Smooth polarized regions that were invisible to aperture-synthesis-only surveys become measurable, while small-scale RM structure is preserved.
  • The same feathering recipe can be applied to future broadband combinations of single-antenna and interferometric polarization surveys, where wider frequency coverage should also resolve the Faraday complexity that the 35 MHz bandwidth cannot.
  • RM values derived from the narrow bandwidth must be treated as narrow-band estimates; the paper's comparison with the full GMIMS-HBN Faraday depth cube shows systematic magnitude differences that future broadband surveys will quantify.
  • Regions around bright sources such as Cygnus X, Cassiopeia A, and W3 carry instrumental-polarization artifacts and should be excluded until better leakage corrections are developed.

Reading between the lines

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

  • The paper's longitude-binned comparison hints that the 26 m single-antenna component dominates the combined RM pattern; a clean test would be to recompute the full-scale RMs with the single-antenna short spacings explicitly masked, to see whether the aperture-synthesis-only longitude trend reappears.
  • The success of the four-channel linear fit opens the door to recombining historical narrow-band polarization datasets wherever single-antenna and interferometric observations overlap in frequency, potentially extending full-scale RM coverage backward in time.
  • A natural extension is to apply the same method at lower frequencies, where Faraday depth sensitivity is higher but Faraday complexity is more severe, testing whether the narrow-band RM caveat becomes prohibitive.
  • If the simulated 6% error holds away from bright sources, the full-scale RM maps could also serve as priors for RM-synthesis cleaning of broadband data, helping to constrain Faraday complexity along each line of sight.
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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

4 major / 5 minor

Summary. The paper presents a proof-of-concept combination of single-antenna (GMIMS-HBN) and aperture-synthesis (CGPS Synthesis Telescope) Stokes Q/U data in four 7.5 MHz channels centred near 1420 MHz. The combination uses Gaussian-beam deconvolution in the uv plane, feathering of the two datasets, and mosaicking, after which per-pixel rotation measures are computed from linear fits of polarization angle against wavelength squared over the 35 MHz bandwidth. The resulting RM and PI maps cover the CGPS longitude range, are compared with ST-only, GMIMS-HBN-only, and broadband Faraday-depth data, and are interpreted in three regions (Sh2-216, IC 443, and the l = 173 deg H II complex). The authors state clear caveats about the narrow bandwidth, the impossibility of detecting Faraday complexity, a uv-coverage gap, and several known artifacts. The central claim is that this is the first full-scale polarization dataset combining single-antenna and aperture-synthesis data across multiple frequency channels, enabling diffuse-emission Faraday rotation studies of all spatial scales down to 3 arcmin.

Significance. If the method is sound, this is a useful pioneering data product: it is the first demonstration that diffuse Galactic RM information can be obtained from combined single-antenna and aperture-synthesis data across separate frequency channels, and it highlights a path for future broadband surveys (e.g., CHIME/DRAGONS, PEGASUS/POSSUM). The processing is transparently documented, the data products are public, and the comparison with L10, Dwingeloo, and compact-source RMs provides a degree of external grounding. The main caveat is that the short-spacing correction rests on a Gaussian beam model and a feathering procedure whose validation is partly circular and excludes known artifacts; because all four frequency channels are processed identically, any error there becomes a common-mode systematic in the RM maps. The paper's own discussion of the narrow-bandwidth lever-arm problem also shows that the numerical RM values are not simply the Faraday depths of the lines of sight. For these reasons the significance is real but conditional on the additional uncertainty quantification described in the major comments.

major comments (4)
  1. [§3.4.2] The simulation validates the feathering pipeline but not the Gaussian beam model that is the crux of the short-spacing correction. The simulated single-antenna image is generated by filtering the true image with the same 9 m HWHM Gaussian that is later deconvolved via Eq. (3), so any error in the beam model is invisible to the test. The reported 6% Stokes U error therefore applies only to the uv-coverage gap, not to beam-model systematics. Because all four frequency channels are processed identically, a beam-model error would introduce a common-mode bias in Stokes Q and U and hence in RM, rather than merely extra random noise. The authors should either validate the Gaussian beam model with an independent measurement or estimate the sensitivity of the final Q, U, and RM maps to plausible beam-model variations.
  2. [§3.1(iii) and §3.2] The GMIMS-HBN data are used in the feathering out to 17.144 m although the data are described as reliable only to roughly 9 m. Figure 4b shows the deconvolved single-antenna visibilities diverging from the ST beyond about 15 m, and Figure 5 shows ratio distributions peaking between 1 and 1.5 with a wide spread, so the overlap region is noisy and not perfectly matched. The manuscript interprets these as tolerable, but no quantitative estimate is given for how the overlap-region mismatch propagates into RM uncertainties; the simulation in §3.4.2 injects noise only at the maximum baseline and reports one residual realization. A per-pixel or per-spatial-scale uncertainty map for Stokes Q, U, and RM, or at least a plausible upper bound on the systematic RM bias from this region, is needed to support the 'all spatial scales' claim.
  3. [§5.3, Figure 21] The comparison between the narrowband RMs and the broadband GMIMS-HBN peak Faraday depths shows a large systematic offset (note the different vertical scales in panels b and c), and the ST-only diffuse RMs trace a different large-scale longitude pattern than the combined or single-antenna RMs. The paper attributes this to an inadequate lever arm and beam depolarization, but the consequence is that the derived RM values are not simply 'the' Faraday depth of each line of sight. Since the abstract and §6 nevertheless present the RM maps as the central product, the text should state more explicitly which quantitative statements (morphology, gradients, sign changes) are robust to this systematic effect and which are not. This is particularly important because §4.2 already states that Faraday complexity cannot be detected and that the RM values should be interpreted with caution.
  4. [§4.2, §5.2, Data Availability] The RM maps are masked only by a PI threshold; no per-pixel uncertainties or fit-quality maps are provided with the released data. The sample fits in Figure 15 show RM uncertainties of tens of rad m^-2, but there is no way for a reader to assess which map features are significant. Since the FITS data products are publicly released, the authors should provide uncertainty maps (from the linear-fit covariance, including the correlated systematic component from the single-antenna processing) together with the RM, PI, Q, and U maps.
minor comments (5)
  1. [Title] The title contains an intra-word space in 'F araday'; this should be corrected to 'Faraday'.
  2. [Figure 21 caption] The caption refers to a '(green)' symbol for the CGPS point sources, but no green symbol is identified in the visible legend; please clarify the legend or the caption.
  3. [§2.2] The manuscript states that the initial instrumental polarization was estimated at 3% of total intensity and later reports 0.3% remaining leakage; a brief sentence explaining whether 0.3% refers to the residual after the iterative correction would remove ambiguity.
  4. [§3.2] The statement that feathering boundaries were chosen as 'integer multiples of the spacing between adjacent elliptical tracks' would be clearer if the relevant spacing in meters were stated explicitly, alongside the values 8.572 m and 17.144 m.
  5. [§4.1 and §4.2] The hook-shaped artifact at l = 120 deg, the rings around Cas A and W3, and the Cygnus X leakage are mentioned in the text, but the RM maps themselves do not mark these regions; a few additional contours or shaded regions on the figures would help readers avoid misinterpreting artifacts as real structures.

Circularity Check

1 steps flagged · score 2.0 of 10

Minor but real circularity in the uv-gap simulation: the simulated single-antenna data are generated with the same 9-m Gaussian beam that is later deconvolved, so the simulation cannot validate the beam model; the central RM derivation is otherwise independent.

  1. other [Section 3.1(iii) and Section 3.4.2]
    "To model the GMIMS-HBN Fourier-transformed beam, we used a Gaussian with a half-width at half-maximum of 9 m in the uv-plane, which corresponds to the 40′ spatial resolution of the 26 m single-antenna telescope. ... We simulated the single-antenna data (Figure 6b) by filtering this image in the uv domain using a Gaussian with half-power at 9 m."

    The deconvolution step divides the GMIMS-HBN visibilities by the Fourier transform of a Gaussian beam with 9 m HWHM (Section 3.1 iii). The mock observation used to validate the combination generates the simulated single-antenna image by convolving the true image with the same 9-m Gaussian. Any error in this beam model is therefore present in both the simulated input and the deconvolution and cancels by construction. The residual of 0.008 K and the resulting ~6% error estimate measure only the feathering pipeline under an assumed beam, not the fidelity of the actual beam correction.

full rationale

The paper's central product—RM maps derived from combined GMIMS-HBN and CGPS Stokes Q/U data—is obtained by a standard linear fit of polarization angle versus wavelength squared to measured Q and U; no model parameter is fitted to the target RM values. The combination pipeline uses a fixed, stated Gaussian beam model and explicit feathering weights; these are assumptions, not outputs of the analysis. The only step exhibiting a by-construction equivalence is the simulation in Section 3.4.2: the simulated single-antenna observation is defined by convolving the 'true' L10 image with the same 9-m Gaussian that Section 3.1(iii) later deconvolves, so the simulation cannot validate the beam model and the reported residual is partly forced by construction. This is genuine but bounded circularity in the validation of the uv-gap stitching; it does not affect the direct computation of RMs from the combined maps. External checks—comparison with the Dwingeloo maps, CGPS point-source and diffuse RMs, and the full-band GMIMS-HBN Faraday depth cube—provide independent support for broad consistency of the data products. The paper also explicitly discloses artifacts (Cygnus X leakage, Cas A and W3 rings, the ℓ=120° hook, the ℓ=180° discontinuity) and repeatedly cautions that RM values should be interpreted with caution given the narrow 35 MHz bandwidth, so the central claim is not being shielded by the circular validation. The overall circularity score is therefore low: 2.

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

No free parameters are fitted to produce the central claim; the listed parameters are procedural choices. The key domain assumptions are the Faraday simplicity of the medium over the narrow band and the accuracy of the beam model and missing-spacing bridge.

free parameters (5)
  • GMIMS-HBN beam model in uv-plane = Gaussian HWHM 9 m
    Used to deconvolve the single-antenna beam (Section 3.1 iii, Eq. 3). The true beam shape may differ from a Gaussian; errors propagate into the combined visibilities and RMs.
  • Feathering boundaries = 8.572 m to 17.144 m with cubic weights
    Selected as integer multiples of the DRAO ST uv-spacing (Section 3.2). These choices define how the two datasets are weighted in overlap; validated only by simulation (Section 3.4.2).
  • Low-pass filter cutoff = 18 m
    Applied to GMIMS-HBN visibilities after beam deconvolution (Section 3.1 iii). The choice suppresses high spatial frequency noise but may remove real structure near the cutoff.
  • Primary beam taper for ST = cos^6 with FWHM 107.2'
    Used to taper GMIMS-HBN images to the ST field of view (Section 3.1 iv); a standard but approximate model.
  • Smoothing and grid = 3 arcmin Gaussian, 0.01 deg grid
    Applied to final maps (Section 3.3); degrades resolution to reduce noise.
assumptions (4)
  • standard math Faraday rotation linear relation (Eq. 1): Delta tau = 0.81 lambda^2 integral n_e B_parallel dl = lambda^2 RM
    Standard physics underlying the RM calculation.
  • domain assumption The magnetoionic medium along each LOS is Faraday simple enough that a linear fit over the 35 MHz band yields a representative RM, or the deviation is a Burn slab where the narrow-band slope approximates half the slab depth.
    Invoked in Sections 4.2 and 5.3; the paper itself shows evidence of Faraday complexity in roughly 90% of the map, so this assumption is fragile.
  • domain assumption The GMIMS-HBN and DRAO ST polarization angle calibrations are aligned after converting to Galactic coordinates; no inter-survey absolute angle offset is applied.
    Section 3.3 mentions rotating polarization angles accordingly, but the paper does not describe a cross-calibration between the two surveys' absolute zero-points.
  • domain assumption The Gaussian model for the GMIMS-HBN beam is accurate enough for deconvolution.
    Section 3.1 iii; the deconvolution divides by the Fourier transform of a guessed beam.

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Cite this review

Pith. "Pith review of A pioneering experiment combining single-antenna and aperture-synthesis data to measure Faraday rotation with GMIMS and the CGPS." pith.science (2026). https://pith.science/paper/E3N42HYS

@misc{pith2026250110623,
  author       = {Pith},
  title        = {Pith review of: A pioneering experiment combining single-antenna and aperture-synthesis data to measure Faraday rotation with GMIMS and the CGPS},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/E3N42HYS}},
  note         = {Machine review of arXiv:2501.10623}
}
abstract

Structures in the magnetoionic medium exist across a wide range of angular sizes owing to large-scale magnetic fields coherent over the Galactic spiral arms combined with small-scale fluctuations in the magnetic field and electron density resulting from energy injection processes such as supernovae. For the first time, we produce diffuse Galactic synchrotron emission Faraday rotation maps covering all spatial scales down to $3'$ resolution for magnetic field studies. These maps complement total and polarized intensity maps combining single-antenna and interferometric data that have been produced, such as the Canadian Galactic Plane Survey (CGPS). Combined maps have sensitivity to large scales from the single-antenna component and angular resolution from the interferometric component. We combine Global Magneto-Ionic Medium Survey High-Band North single-antenna and CGPS aperture-synthesis polarization data after spatial filtering, producing Stokes $Q$ and $U$ maps for the four CGPS frequency channels. We calculate rotation measures (RMs) for all pixels using a linear fit to polarization angle versus wavelength squared. Smooth polarized emission regions require the large-scale sensitivity of the single-antenna to illuminate the Faraday rotation, while aperture synthesis reveals small-scale RM variability. While these maps show magnetic field structures on the full range of spatial scales they probe, the RM values should be interpreted with caution, as the narrow $\lambda^2$ coverage limits sensitivity to Faraday complexity. Despite this limitation of the CGPS 35 MHz bandwidth, we demonstrate that useful Faraday rotation information can be obtained from the combined dataset, highlighting the important synergy between future broadband interferometric and single-antenna polarization surveys.

Figures

Figures reproduced from arXiv: 2501.10623 by the authors.

Figure 1
Figure 1. The steps in preparing a GMIMS-HBN map to be combined with the corresponding DRAO ST field. This example shows Stokes U for band B of one of the Ordog-Brown fields (OB12). (a) Tapered GMIMS-HBN map, regridded to match DRAO ST field grid spacing; (b) the GMIMS-HBN field transformed to the uv-plane; (c) the visibilities divided by the single-antenna beam transform to deconvolve the beam from the image; (d) the deconvo… view at source ↗
Figure 2
Figure 2. The steps in feathering GMIMS-HBN and DRAO ST visibilities in order to combine the datasets. This ex￾ample shows Stokes U for band B of field OB12. (a) The deconvolved, low-pass-filtered GMIMS-HBN map tapered to match the primary beam of the DRAO ST; (b) the origi￾nal DRAO ST field; (c) GMIMS-HBN transformed to the uv-plane; (d) DRAO ST transformed to the uv-plane; (e) the GMIMS-HBN visibilities feathered to discard… view at source ↗
Figure 3
Figure 3. Sample mosaics of GMIMS-HBN (left), DRAO ST (middle) and combined data (right) for Stokes U, band B. Regions of bright positive emission covering a few square degrees that are filtered out by the ST are incorporated from the GMIMS-HBN data. 0 5 10 15 20 25 30 35 40 45 50 10 0 10 1 10 2 10 3 u v - pla n e a m plit u d e (a) DRAO ST GMIMS-HBN 0 5 10 15 20 25 30 35 40 45 50 10 0 10 1 10 2 10 3 u v - pla n e a m plit u … view at source ↗
Figures from the paper (17 more)
Figure 5
Figure 5. Figure 5: The distribution of ratios of GMIMS-HBN to DRAO ST polarization data in the uv-plane. The ratio is calculated separately for each band of Stokes Q and U in the region of the uv-plane where the datasets of the 403 CGPS and Ordog-Brown fields used in this experiment are …
Figure 6
Figure 6. Figure 6: Mock observations of a full-scale Stokes U image with the GMIMS-HBN and DRAO ST telescope parameters, and the resulting combined image. (a) The full-scale image. (b) The simulated single-antenna image. (c) The simulated aperture￾synthesis image. (d) The uv-plane covera…
Figure 7
Figure 7. Figure 7: Combined full-scale RM and PI maps for 52◦ < ℓ < 86◦ . Top: RM for pixels with PI> 0.1 K (gray denotes the masked out regions). Bottom: PI calculated as PI = p ⟨Q⟩ 2 + ⟨U⟩ 2 where the averages ⟨Q⟩ and ⟨U⟩ are taken over the four ST frequency channels. These maps includ…
Figure 8
Figure 8. Figure 8: Combined full-scale RM and PI maps for 84◦ < ℓ < 104◦ , as in [PITH_FULL_IMAGE:figures/full_fig_p012_8.png]
Figure 9
Figure 9. Figure 9: Combined full-scale RM and PI maps for 102◦ < ℓ < 122◦ , as in [PITH_FULL_IMAGE:figures/full_fig_p012_9.png]
Figure 10
Figure 10. Figure 10: Combined full-scale RM and PI maps for 120◦ < ℓ < 140◦ , as in [PITH_FULL_IMAGE:figures/full_fig_p013_10.png]
Figure 11
Figure 11. Figure 11: Combined full-scale RM and PI maps for 138◦ < ℓ < 158◦ , as in [PITH_FULL_IMAGE:figures/full_fig_p013_11.png]
Figure 12
Figure 12. Figure 12: Combined full-scale RM and PI maps for 156◦ < ℓ < 176◦ , as in [PITH_FULL_IMAGE:figures/full_fig_p014_12.png]
Figure 13
Figure 13. Figure 13: Combined full-scale RM and PI maps for 174◦ < ℓ < 194◦ , as in [PITH_FULL_IMAGE:figures/full_fig_p014_13.png]
Figure 14
Figure 14. Figure 14: Stokes Q (left) and Stokes U (right) power spectra for the GMIMS-HBN single-antenna (purple squares), the DRAO ST (blue circles) and the combined data (red diamonds). Rows (a)-(g) correspond to the regions shown in Figures 7-13, with the Cygnus X longitudes excluded f…
Figure 15
Figure 15. Figure 15: Sample linear fit RM values for three lines of sight, comparing the single-antenna-only data (GMIMS-HBN; purple, denoted ‘HBN’), aperture-synthesis-only data (DRAO ST; blue, denoted ‘ST’), and the combined full-scale data (red, denoted ‘full’). The bottom panels show …
Figure 16
Figure 16. Figure 16: The GMIMS-HBN, DRAO ST, and full-scale data in the Sh2-216 PN region. Top row (a-c): PI calculated as P I = p ⟨Q⟩ 2 + ⟨U⟩ 2. Bottom row (d-f): RM for pixels with PI> 0.1 K. Left column (a,d): GMIMS-HBN single-antenna-only data. Middle column (b,e): DRAO ST aperture-sy…
Figure 17
Figure 17. Figure 17: The northeast arc of Sh2-216 showing the ‘po￾larization knots’ studied by Ransom et al. (2008, R08) and approximately matching the region shown in their [PITH_FULL_IMAGE:figures/full_fig_p018_17.png]
Figure 18
Figure 18. Figure 18: The GMIMS-HBN, DRAO ST, and full-scale data in the IC 443 SNR region. Panels are the same as in [PITH_FULL_IMAGE:figures/full_fig_p020_18.png]
Figure 19
Figure 19. Figure 19: CGPS Stokes I in the IC 443 supernova remnant region. Black contours indicate PI= 0.25 K on the full-scale map. we highlighted that this negative patch led to the dip in RMs observed as a function of Galactic longitude (Fig￾ure 21a). The presence of negative RMs in th…
Figure 20
Figure 20. Figure 20: The GMIMS-HBN, DRAO ST, and full-scale data in the ℓ = 173◦ H II complex. Panels are the same as in [PITH_FULL_IMAGE:figures/full_fig_p021_20.png]
Figure 21
Figure 21. Figure 21: Rotation Measures and peak Faraday depths as a function of Galactic longitude in the latitude range −3.5 ◦ ≤ b ≤ 5.5 ◦ for diffuse synchrotron emission compared to compact polarized point sources. (a) aperture-synthesis-only data: extragalactic point source RMs from t…

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Forward citations

Cited by 1 Pith paper

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

  1. Faraday depth similarities across scales with LoTSS & DRAGONS

    astro-ph.GA 2026-07 accept novelty 5.5 of 10

    LoTSS and DRAGONS Faraday-depth first-moment maps agree strongly despite no shared frequency or spatial-scale coverage, implying cross-scale coupling in the magnetised ISM.

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Pith tools

Reviewed August 10, 2026 · model on record in the stance chip above.