Pith. sign in

REVIEW 3 major objections 5 minor 1 cited by

Full Stokes magnetometry of the active M dwarfs AU Mic and EV Lac with SPIRou

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

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

Pith's one-line read By fitting all four Stokes parameters, this paper maps AU Mic as a simple rotation-aligned magnetic star and EV Lac as a stronger, more complex one, with kilogauss unresolved fields on both.

desk verdict First full Stokes ZDI maps of M dwarfs: QU data clearly matter, but the EV Lac dipole tilt is one degenerate solution the abstract oversells. read the letter →

arxiv 2507.01754 v1 pith:7A7UUX6M submitted 2025-07-02 astro-ph.SR

J.-F. Donati , P.I. Cristofari , B. Klein , B. Finociety , C. Moutou This is my paper · ORCID
classification astro-ph.SR
keywords magneticfieldsMdwarfsZeeman-DopplerimagingStokespolarimetryAUMicEVLacstellaractivityspectropolarimetry
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 establishes that full Stokes magnetometry—fitting all four polarization states (total intensity, circular polarization, and two orthogonal linear polarizations) simultaneously—changes the magnetic topologies inferred for active M dwarfs. Applying the technique to AU Mic and EV Lac, it finds AU Mic's large-scale field is mostly poloidal and aligned with the rotation axis to within about ten degrees, while EV Lac's is stronger, more complex, and less axisymmetric. The unresolved small-scale fields are intense, about 4 kG on AU Mic and 6 kG on EV Lac. The result matters because Stokes-V-only maps underestimated AU Mic's large-scale field by about a factor of three and made EV Lac's dipole look nearly orthogonal; with all Stokes parameters, EV Lac's field becomes much more like those of other M dwarfs.

What carries the argument

The load-bearing mechanism is a parametric coupling of field scales within Zeeman-Doppler imaging (ZDI), a tomographic technique that turns rotationally modulated spectral profiles into surface magnetic maps. Each surface cell carries a large-scale field $B_P$ and an unresolved small-scale field $B_I = B_P f_I/f_P$, with filling factors $f_P$ and $f_I$ assumed uniform over the star. ZDI then reconstructs the large-scale field as a spherical-harmonic expansion by fitting either Stokes V alone, Stokes I plus V, or all of Stokes I, V, Q and U, together with a brightness map and a photometric light curve. The Stokes QU data are the crucial addition: they carry orientation information that circular polarization of a nearly equator-on or low-$v\sin i$ star cannot provide, breaking degeneracies that otherwise hide large-scale flux.

What would settle it

Measure the Zeeman broadening of Stokes I from independent subsets of lines with different magnetic sensitivities (Landé factors), or from atomic versus molecular lines, and require the same magnetic map and the same global $f_P,f_I$ to fit all of them; a wavelength-dependent or phase-dependent small-to-large ratio would falsify the uniform-scaling assumption and with it the exact dipole tilts and field strengths.

Watch

Extended reading notes

Core claim

The paper's central discovery is that the additional geometric information in Stokes QU linear polarization materially changes the magnetic images. For AU Mic, a Stokes-V-only reconstruction gives a weak, non-axisymmetric 355 G field; including Stokes I and QU yields a roughly 920 G, 97 percent axisymmetric field whose dipole is within about 9 degrees of the rotation axis and stores about 60 percent of the poloidal energy. For EV Lac, the old almost-orthogonal dipole is replaced by a dominant dipole tilted by about 35 degrees, embedded in a stronger and more complex field, with average unresolved small-scale fields of about 4.1 kG and 5.6 kG on AU Mic and EV Lac respectively. The paper also demonstrates that the Stokes QU signatures it detects at most phases are reproducible by the same Zeeman-Doppler imaging model, and that these data are especially useful for low-$v\sin i$ stars like EV Lac.

Load-bearing premise

Everything rests on the assumption that the unresolved small-scale field in every surface cell is a fixed multiple of the large-scale field, with the same two filling factors over the whole star; if the true ratio varies across the surface, with field strength, or with time, the quoted kilogauss values and the recovered topologies are biased.

Editorial extensions

If this is right

  • Stokes V alone underestimates the large-scale fields of strongly magnetized M dwarfs; for AU Mic, adding Stokes I and QU raises the recovered large-scale field from 355 G to about 920 G.
  • EV Lac's dipole is not nearly orthogonal to its rotation axis; its 35-degree tilt makes it more consistent with magnetic topologies of other M dwarfs.
  • Stokes QU data are decisive for low-$v\sin i$ stars with complex fields, where line broadening carries little spatial information about the stellar surface.
  • The potential-field extrapolation of AU Mic's stronger derived field places its transiting planets inside an enlarged Alfvén volume, so star-planet magnetic interaction is plausible.
  • Reconstructions from Stokes IV and IVQU profiles reproduce the independently measured ZeeTurbo small-scale field values, supporting the parametric scaling used in the model.

Reading between the lines

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

  • The authors do not state this, but the same full-Stokes pipeline on a sample of M dwarfs would test whether magnetic complexity tracks Rossby number or flare rate more cleanly than Stokes-V maps do.
  • The uniform scaling assumption in the paper predicts that the large-scale and unresolved small-scale fields modulate in lockstep; a multi-season dataset could check whether the two modulations drift apart.
  • A testable extension the authors do not develop is synthesizing individual atomic and molecular lines from the recovered maps; agreement across line species would validate the global filling-factor ratio, while disagreement would break it.
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 / 5 minor

Summary. This paper presents near-infrared SPIRou spectropolarimetric observations of the active M dwarfs AU Mic and EV Lac taken in 2023 August–October. Using Least-Squares Deconvolution in all four Stokes parameters, the authors detect circular and linear Zeeman signatures as well as Zeeman broadening in Stokes I, and then perform Zeeman-Doppler Imaging (ZDI) using Stokes V, Stokes IV, and Stokes IVQU data, together with brightness reconstructions from photometric light curves. They report that AU Mic has a mostly poloidal, nearly axisymmetric large-scale field aligned with the rotation axis to within about 10 degrees, while EV Lac has a more complex, stronger, and less axisymmetric field with a dipole tilted by about 35 degrees rather than the nearly orthogonal orientation previously reported. From the same modeling, they derive average small-scale fields of about 4 kG for AU Mic and 5.6–6 kG for EV Lac, and argue that including Stokes QU is important for reliable magnetic reconstructions, especially for low-v sin i stars.

Significance. If the full-Stokes ZDI results are robust, the paper would substantially revise the magnetic topology of EV Lac, changing its inferred dipole tilt from roughly orthogonal to ~35 degrees, with consequences for dynamo models and flare-activity interpretations. The paper also demonstrates a methodological advance: it is among the first to apply ZDI to all four Stokes parameters for low-mass stars using SPIRou, and the internal validation—showing that Stokes V–only fits badly reproduce the observed QU profiles—makes a convincing qualitative case that linear polarization adds information. The observational data set is of high quality and the paper reaches photon-noise-limited fits. However, the absolute values of the large- and small-scale field strengths rest on a parametric relation between the two, and the EV Lac topology is derived from a mathematically underdetermined inversion whose non-uniqueness the authors themselves acknowledge.

major comments (3)
  1. [§4.2 and Table 2] The central claim that EV Lac's dipole is tilted by about 35 degrees (rather than the nearly orthogonal value of Morin et al. 2008 and Bellotti et al. 2024) rests on a single maximum-entropy solution to a severely ill-posed inversion: §4.1 states that EV Lac has only ~54 independent data points for 360 spherical-harmonic parameters, and §4.2 and §5 admit that 'different, even more complex magnetic topologies may also exist for EV Lac, matching equally well the LSD Stokes IV QU data.' The abstract, however, calls the maps 'reliable' and the dipole tilt is presented as a firm result in the summary ('not highly tilted'). To support this load-bearing claim, the authors should demonstrate that the recovered dipole tilt and energy partition are stable under (a) different random or zero initial seeds, (b) variations of the spherical-harmonic truncation order (e.g., ℓmax = 5, 8, 12), and (c) different regularization strengths. Alternatively, they should present an ensemble of equally good solutions and show that the ~35 degree tilt is a robust feature; without such an analysis, the EV Lac topology claim is not uniquely constrained by the data.
  2. [§4.1, relation BI = BP fI/fP] The quoted field strengths—<BP> ≈ 920 G and <BI> ≈ 4.1 kG for AU Mic, <BP> ≈ 845 G and <BI> ≈ 5.6 kG for EV Lac (Table 2)—inherit the assumed scaling between small-scale and large-scale fields, BI = BP fI/fP, with uniform filling factors fP and fI over the whole stellar surface. This parametric relation is a modeling choice, not a measured law. The apparent consistency with the ZeeTurbo small-scale field measurements (Fig. 6) is not fully independent, because the <BI> values shown in that figure are obtained by applying the same assumed relation to the reconstructed BP maps. The authors should report a sensitivity analysis in which fP and fI are varied over plausible ranges, showing how <BP>, <BI>, the dipole tilt, and the ZeeTurbo comparison change. At minimum, the abstract should avoid presenting the 4 kG and 6 kG values as directly measured quantities.
  3. [§5, discussion of AU Mic's Alfvén surface] In the discussion (end of §5), the paper states that the stronger dipole field of AU Mic implies a wider Alfvén volume, placing both transiting planets inside it. This prediction is contingent on the large-scale field strength derived from the fI/fP scaling, which is itself a free parameter. In addition, the field strength error bar quoted in Table 2 (10 percent) reflects only the formal fitting uncertainty under the chosen parameter set, not the systematic uncertainty of the parametric assumption. The authors should either soften this astrophysical inference or condition it explicitly on the as-yet-unquantified model-dependent scale.
minor comments (5)
  1. [Abstract and §4.2] The abstract states 'aligned with the rotation axis within about 10deg' while Table 2 gives a tilt of 9 degrees for the Stokes IVQU reconstruction; use consistent notation and cite the value with its uncertainty (5 degrees).
  2. [Table 2] The column header 'axisymetry' is misspelled; it should be 'axisymmetry'. In addition, the table columns are not clearly labeled as the V, IV, and IVQU cases for each star; a header row such as 'AU Mic: V, IV, IVQU, EV Lac: V, IV, IVQU' would aid readability.
  3. [Fig. 7 caption] The sentence 'The color scale depicts the radial field value at the surface of the star (in G), as derived by ZDI' appears twice in the caption; delete the duplicate.
  4. [§3] The text says 'we obtained Stokes IQU spectra of AU Mic and IQUV observations of EV Lac'; since Stokes IQUV denotes all four parameters, the distinction between IQU and IQUV is confusing. Clarify that AU Mic had Stokes IV data secured under the SPICE programme and IQU data from the main programme.
  5. [Fig. 6 and Table 2] The caption of Fig. 6 defines <BI> as the small-scale field 'computed over the visible (limb darkened) stellar hemisphere', while the note to Table 2 defines <BI> as 'quadratically averaged over the whole star'. These definitions are inconsistent and should be aligned or explicitly distinguished (e.g., <BI> for the whole star and <BI,vis> for the visible hemisphere).

Circularity Check

1 steps flagged · score 2.0 of 10

No load-bearing circularity: the central magnetic topologies are inversion outputs from observed Stokes IVQU data, with the only definitional element being the parametric scaling of the small-scale field from the large-scale field, which is transparent and checked against independent ZeeTurbo measurements.

  1. self definitional [Sec. 4.1 (parametric small-scale/large-scale relation) and Table 2]
    "Similarly, we assume that a fraction fI of each grid cell (called filling factor of the small-scale field, again equal for all cells) hosts small-scale fields of strength BP/fP, implying a small-scale magnetic flux over the whole cell equal to BI = BP fI/fP."

    The whole-star small-scale field quoted in the abstract and Table 2 is not an independent ZDI output: with fI/fP fixed at 0.9/0.2 for AU Mic and 1.0/0.15 for EV Lac, every <BI> entry is exactly <BP> times the chosen ratio (e.g., 920 G x 4.5 = 4.1 kG; 845 G x 6.67 = 5.6 kG). The 'intense small-scale fields of about 4 kG and 6 kG' therefore reduce by construction to the fitted large-scale field once the parametric ansatz is adopted. The paper is transparent about the assumption, and the external ZeeTurbo comparison (Fig. 6) provides independent support, so this is a minor definitional step rather than full circularity.

full rationale

The paper's central results are the large-scale magnetic topologies of AU Mic and EV Lac, reconstructed by fitting observed LSD Stokes V, I, Q and U profiles with ZDI. These maps are genuine inversion outputs, not quantities defined in terms of the claimed conclusion. The EV Lac dipole-tilt claim rests on a regularized solution that the authors themselves state is non-unique (Secs. 4.2 and 5), but degeneracy of an ill-posed inversion is a robustness/correctness concern, not a circularity. The synthetic Stokes QU profiles predicted from the Stokes V and IV maps are compared with observed QU data not used in those fits, providing a real (though partial) external check. The only definitional reduction is the small-scale field, which is computed as BI = BP fI/fP with constant filling factors; this makes the quoted 4-6 kG small-scale field strengths a rescaling of the reconstructed large-scale field. This step is explicit in Sec. 4.1 and is independently cross-checked against ZeeTurbo measurements in Fig. 6, so it does not vitiate the paper's main derivation. No load-bearing self-citation or imported uniqueness theorem is involved; citations to Donati et al. (2023a) concern the established ZDI/Stokes-IV methodology rather than the present conclusions. Overall circularity is low.

Assumptions & free parameters 6 free parameters · 5 assumptions · 0 invented entities

The central claim rests on modeling assumptions rather than new physics. The ZDI inversion assumes a single-depth Milne-Eddington atmosphere, represents about 1500 LSD lines as one Zeeman triplet, couples small-scale to large-scale fields through a fixed parametric ratio with hand-tuned filling factors, and relies on maximum-entropy regularization to pick a unique image. No novel physical entities are postulated.

free parameters (6)
  • Doppler width vD = 5.3 km/s (V-only) and 3.5 km/s (IV, IVQU) for both stars
    Set by hand to match the width of LSD Stokes I profiles; switching between values changes the inferred large-scale and small-scale field strengths (Sec. 4.1, Table 2).
  • Large-scale filling factor fP = 0.2 (AU Mic), 0.15 (EV Lac)
    Chosen to match observed Stokes V QU amplitudes and adopted from earlier work; scales the large-scale field strength in each cell (Sec. 4.2, Table 2).
  • Small-scale filling factor fI = 0.9 (AU Mic), 1.0 (EV Lac)
    Adopted from Cristofari et al. (2023); controls the Zeeman broadening and the derived small-scale field <BI> through BI = BP fI/fP (Sec. 4.2, Table 2).
  • Inclination i = 80 deg (AU Mic), 60 deg (EV Lac)
    Not fitted; assumed for ZDI from prior literature (Table 1). Error in i would affect the deprojection of the magnetic geometry.
  • Linear limb-darkening coefficient = 0.3
    Assumed for the continuum in the radiative transfer integration (Sec. 4.1); affects the weights of surface cells in the disk integration.
  • Spherical harmonics truncation order = l = 10
    Chosen because of the modest vsini of both stars; limits the spatial resolution of the reconstructed magnetic maps (Sec. 4.1).
assumptions (5)
  • domain assumption Unno-Rachkovsky equation with a plane-parallel Milne-Eddington atmosphere describes local Stokes IVQU line formation.
    Used to compute local synthetic profiles in ZDI (Sec. 4.1). This is standard polarized radiative transfer but is an approximation for real stellar atmospheres.
  • domain assumption The LSD profile of roughly 1500 real lines can be represented by a single Zeeman-triplet virtual line with mean wavelength 1700 nm and mean Lande factor 1.2.
    Acknowledged in Sec. 4.1 as a challenge for strongly magnetic stars; calibration is achieved by tuning vD, fP and fI.
  • ad hoc to paper Small-scale and large-scale fields relate by BI = BP fI/fP with uniform filling factors fP and fI over the entire stellar surface.
    Introduced in Sec. 4.1 to reproduce the coexistence of small- and large-scale fields; no independent justification is provided, and the field strengths in Table 2 depend on it.
  • domain assumption Maximum-entropy regularization selects the true magnetic image among degenerate inversions.
    ZDI is said to produce a unique solution 'by construction' (Sec. 4.1), but the authors admit EV Lac remains degenerate with possible alternative topologies fitting the data equally well (Sec. 4.2).
  • domain assumption Stellar parameters (Prot, vsini, M, R) adopted from prior literature are accurate.
    Table 1 adopts rotation periods, vsini and inclination from earlier papers; the phasing of observations and the mapping from velocities to surface coordinates depend on these values.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Full Stokes magnetometry of the active M dwarfs AU Mic and EV Lac with SPIRou." pith.science (2026). https://pith.science/paper/7A7UUX6M

@misc{pith2026250701754,
  author       = {Pith},
  title        = {Pith review of: Full Stokes magnetometry of the active M dwarfs AU Mic and EV Lac with SPIRou},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/7A7UUX6M}},
  note         = {Machine review of arXiv:2507.01754}
}
read the original abstract

We report in this paper circularly and linearly polarized observations of the young active M dwarfs AU Mic and EV Lac with the near-infrared SPIRou spectropolarimeter at the Canada-France-Hawaii Telescope, collected from August to October 2023 over a few rotation cycles of both stars. Applying Least-Squares Deconvolution (LSD) to our spectra, we detected Zeeman signatures in circular (Stokes V) and linear (Stokes QU) polarization, and Zeeman broadening in unpolarized (Stokes I) LSD profiles, all exhibiting clear rotational modulation. Using the stellar surface tomographic technique of Zeeman-Doppler imaging on our sets of observations, along with a simple parametric description of how the small-scale and large-scale fields relate to each other, we recovered the magnetic topologies of AU Mic and EV Lac successively from LSD Stokes V, Stokes IV and Stokes IVQU profiles, to investigate how the reconstructed maps evolve as we provide more information, and ultimately infer reliable magnetic maps of both stars. We find that AU Mic hosts a fairly simple and mostly poloidal large-scale field aligned with the rotation axis within about 10deg, whereas that of EV Lac is more complex, stronger and less axisymmetric. Both stars feature intense small-scale fields, of about 4 kG for AU Mic and 6 kG for EV Lac when averaged over the whole stellar surface. Stokes QU Zeeman signatures allow one to reconstruct stellar magnetic fields more reliably, and are especially useful for stars with more complex fields and low vsini's like EV Lac.

Figures

Figures reproduced from arXiv: 2507.01754 by the authors.

Figure 1
Figure 1. Observed (thick black line) and modelled (thin color [PITH_FULL_IMAGE:figures/full_fig_p005_1.png] view at source ↗
Figure 2
Figure 2. Reconstructed maps of the large-scale magnetic field [PITH_FULL_IMAGE:figures/full_fig_p006_2.png] view at source ↗
Figure 3
Figure 3. Same as Fig. 2 for EV Lac [PITH_FULL_IMAGE:figures/full_fig_p007_3.png] view at source ↗
Figures from the paper (4 more)
Figure 4
Figure 4. Figure 4: Photometric light curves inferred from dT estimates (red circles, left panels) with ZDI fits (green curves), and brightness maps (right panels) reconstructed simultaneously with the magnetic maps of Figs. 2 and 3, for both AU Mic (top row) and EV Lac (bottom row), in t…
Figure 5
Figure 5. Figure 5: Same as the two rightmost panels of Fig. 1, showing now [PITH_FULL_IMAGE:figures/full_fig_p009_5.png]
Figure 6
Figure 6. Figure 6: Rotational modulation of the small-scale field [PITH_FULL_IMAGE:figures/full_fig_p009_6.png]
Figure 7
Figure 7. Figure 7: Potential field extrapolation of the large-scale fiel [PITH_FULL_IMAGE:figures/full_fig_p010_7.png]

Discussion (0). Continue with ORCID to comment.

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. Unstable magnetospheric accretion on the T Tauri star TW Hya

    astro-ph.SR 2026-07 accept novelty 4.5 of 10

    TW Hya’s large-scale field is a ~0.83 kG tilted dipole that varies yearly; accretion is unstable (rmag/rcor ≈ 0.33–0.40) and no close-in planet is detected above ~0.3–1 Mjup.

Reference graph

Works this paper leans on

78 extracted references · 58 canonical work pages · cited by 1 Pith paper

  1. [1]

    D., Cohen , O., Drake , J

    Alvarado-G \'o mez , J. D., Cohen , O., Drake , J. J., et al. 2022, , 928, 147

    2022

  2. [2]

    J., et al

    Artigau , \'E ., Cadieux , C., Cook , N. J., et al. 2024, , 168, 252

    work page 2024

  3. [3]

    J., et al

    Artigau , \'E ., Cadieux , C., Cook , N. J., et al. 2022, , 164, 84

    2022

  4. [4]

    2018, , 155, 198

    Artigau , \'E ., Malo , L., Doyon , R., et al. 2018, , 155, 198

    work page 2018

  5. [5]

    2015, , 577, A42

    Baraffe , I., Homeier , D., Allard , F., & Chabrier , G. 2015, , 577, A42

    2015

  6. [6]

    T., et al

    Bellotti , S., Morin , J., Lehmann , L. T., et al. 2024, , 686, A66

    work page 2024

  7. [7]

    R., Vedantham , H

    Bloot , S., Callingham , J. R., Vedantham , H. K., et al. 2024, , 682, A170

    work page 2024

  8. [8]

    M., et al

    Boccaletti , A., Sezestre , E., Lagrange , A. M., et al. 2018, , 614, A52

    work page 2018

Show all 78 references
  1. [9]

    2015, , 526, 230

    Boccaletti , A., Thalmann , C., Lagrange , A.-M., et al. 2015, , 526, 230

    2015

  2. [10]

    M., Kriskovics , L., et al

    Boldog , \'A ., Szab \'o , G. M., Kriskovics , L., et al. 2025, , 694, A137

    2025

  3. [11]

    V., et al

    Boro Saikia , S., Lueftinger , T., Jeffers , S. V., et al. 2018, , 620, L11

    2018

  4. [12]

    L., Reefe , M., Plavchan , P., et al

    Cale , B. L., Reefe , M., Plavchan , P., et al. 2021, , 162, 295

    2021

  5. [13]

    J., Artigau , \'E ., Doyon , R., et al

    Cook , N. J., Artigau , \'E ., Doyon , R., et al. 2022, , 134, 114509

    2022

  6. [14]

    I., Donati , J.-F., Belloti , S., et al

    Cristofari , P. I., Donati , J.-F., Belloti , S., et al. 2025, , submitted

    2025

  7. [15]

    I., Donati , J

    Cristofari , P. I., Donati , J. F., Folsom , C. P., et al. 2023, , 522, 1342

    2023

  8. [16]

    I., Donati , J

    Cristofari , P. I., Donati , J. F., Masseron , T., et al. 2022, , 511, 1893

    2022

  9. [17]

    & Landstreet , J

    Donati , J. & Landstreet , J. D. 2009, , 47, 333

    2009

  10. [18]

    F., Semel , M., et al

    Donati , J.-F., Brown , S. F., Semel , M., et al. 1992 a , , 265, 682

    1992

  11. [19]

    F., Cristofari , P

    Donati , J. F., Cristofari , P. I., Finociety , B., et al. 2023 a , , 525, 455

    2023

  12. [20]

    I., Moutou , C., et al

    Donati , J.-F., Cristofari , P. I., Moutou , C., et al. 2025, , submitted

    2025

  13. [21]

    F., Finociety , B., Cristofari , P

    Donati , J. F., Finociety , B., Cristofari , P. I., et al. 2024, , 530, 264

    2024

  14. [22]

    D., Jardine , M

    Donati , J.-F., Howarth , I. D., Jardine , M. M., et al. 2006, , 370, 629

    2006

  15. [23]

    F., Kouach , D., Moutou , C., et al

    Donati , J. F., Kouach , D., Moutou , C., et al. 2020, , 498, 5684

    2020

  16. [24]

    F., Lehmann , L

    Donati , J. F., Lehmann , L. T., Cristofari , P. I., et al. 2023 b , , 525, 2015

    2023

  17. [25]

    D., Rees , D

    Donati , J.-F., Semel , M., Carter , B. D., Rees , D. E., & Collier Cameron , A. 1997, , 291, 658

    1997

  18. [26]

    F., Semel , M., & Rees , D

    Donati , J. F., Semel , M., & Rees , D. E. 1992 b , , 265, 669

    1992

  19. [27]

    Engle , S. G. 2024, , 960, 62

    2024

  20. [28]

    F., Moutou , C., et al

    Fares , R., Donati , J. F., Moutou , C., et al. 2009, , 398, 1383

    2009

  21. [29]

    2000, , 353, 987

    Favata , F., Reale , F., Micela , G., et al. 2000, , 353, 987

    2000

  22. [30]

    Feiden , G. A. 2016, , 593, A99

    2016

  23. [31]

    D., France , K., Youngblood , A., et al

    Feinstein , A. D., France , K., Youngblood , A., et al. 2022, , 164, 110

    2022

  24. [32]

    & Donati , J

    Finociety , B. & Donati , J. F. 2022, , 516, 5887

    2022

  25. [33]

    F., et al

    Fouqu \'e , P., Martioli , E., Donati , J. F., et al. 2023, , 672, A52

    2023

  26. [34]

    Gaia Collaboration , Brown , A. G. A., Vallenari , A., et al. 2021, , 649, A1

    2021

  27. [35]

    2022, , 665, A41

    Gallenne , A., Desgrange , C., Milli , J., et al. 2022, , 665, A41

    2022

  28. [36]

    M., Donati , J

    H \'e brard , \'E . M., Donati , J. F., Delfosse , X., et al. 2016, , 461, 1465

    2016

  29. [37]

    V., Buccino , A

    Iba \ n ez Bustos , R. V., Buccino , A. P., Flores , M., et al. 2019, , 483, 1159

    2019

  30. [38]

    Johns-Krull , C. M. & Valenti , J. A. 1996, , 459, L95+

    1996

  31. [39]

    D., Vidotto , A

    Kavanagh , R. D., Vidotto , A. A., Klein , B., et al. 2021, , 504, 1511

    2021

  32. [40]

    2021, , 502, 188

    Klein , B., Donati , J.-F., Moutou , C., et al. 2021, , 502, 188

    2021

  33. [41]

    D., et al

    Klein , B., Zicher , N., Kavanagh , R. D., et al. 2022, , 512, 5067

    2022

  34. [42]

    2021, , 29, 1

    Kochukhov , O. 2021, , 29, 1

    2021

  35. [43]

    A., et al

    Kochukhov , O., Bagnulo , S., Wade , G. A., et al. 2004, , 414, 613

    2004

  36. [44]

    Kochukhov , O., Hackman , T., & Lehtinen , J. J. 2023, , 680, L17

    2023

  37. [45]

    & Reiners , A

    Kochukhov , O. & Reiners , A. 2020, , 902, 43

    2020

  38. [46]

    & Landolfi , M

    Landi degl'Innocenti , E. & Landolfi , M. 2004, Polarisation in spectral lines (Dordrecht/Boston/London: Kluwer Academic Publishers)

    2004

  39. [47]

    E., Leisenring , J

    Lawson , K., Schlieder , J. E., Leisenring , J. M., et al. 2023, , 166, 150

    2023

  40. [48]

    Lehmann , L. T. & Donati , J. F. 2022, , 514, 2333

    2022

  41. [49]

    T., Donati , J

    Lehmann , L. T., Donati , J. F., Fouqu \'e , P., et al. 2024, , 527, 4330

    2024

  42. [50]

    Mallorqu \' n , M., B \'e jar , V. J. S., Lodieu , N., et al. 2024, , 689, A132

    2024

  43. [51]

    Martioli , E., H \'e brard , G., Correia , A. C. M., Laskar , J., & Lecavelier des Etangs , A. 2021, , 649, A177

    2021

  44. [52]

    2010, , 407, 2269

    Morin , J., Donati , J., Petit , P., et al. 2010, , 407, 2269

    2010

  45. [53]

    2008, , 390, 567

    Morin , J., Donati , J.-F., Petit , P., et al. 2008, , 390, 567

    2008

  46. [54]

    R., Barclay , T., Youngblood , A., et al

    Paudel , R. R., Barclay , T., Youngblood , A., et al. 2024, , 971, 24

    2024

  47. [55]

    2005, in EAS Publications Series, Vol

    Piskunov , N. 2005, in EAS Publications Series, Vol. 17, EAS Publications Series, ed. G. Alecian , O. Richard , & S. Vauclair , 245--250

    2005

  48. [56]

    2020, , 582, 497

    Plavchan , P., Barclay , T., Gagn \'e , J., et al. 2020, , 582, 497

    2020

  49. [57]

    2012, Living Reviews in Solar Physics, 9, 1

    Reiners , A. 2012, Living Reviews in Solar Physics, 9, 1

    2012

  50. [58]

    & Basri , G

    Reiners , A. & Basri , G. 2007, , 656, 1121

    2007

  51. [59]

    J., et al

    Reiners , A., Shulyak , D., K \"a pyl \"a , P. J., et al. 2022, , 662, A41

    2022

  52. [60]

    2024, , 532, 2741

    Rescigno , F., Mortier , A., Dumusque , X., et al. 2024, , 532, 2741

    2024

  53. [61]

    D., Worden , S

    Robinson , R. D., Worden , S. P., & Harvey , J. W. 1980, , 236, L155

    1980

  54. [62]

    Ros \'e n , L., Kochukhov , O., & Wade , G. A. 2015, , 805, 169

    2015

  55. [63]

    L., et al

    Ryabchikova , T., Piskunov , N., Kurucz , R. L., et al. 2015, , 90, 054005

    2015

  56. [64]

    Saar , S. H. & Linsky , J. L. 1985, , 299, L47

    1985

  57. [65]

    A., et al

    See , V., Jardine , M., Vidotto , A. A., et al. 2015, , 453, 4301

    2015

  58. [66]

    & Bryan , R

    Skilling , J. & Bryan , R. K. 1984, , 211, 111

    1984

  59. [67]

    S., Matt , S

    Strugarek , A., Brun , A. S., Matt , S. P., & R \'e ville , V. 2015, , 815, 111

    2015

  60. [68]

    M., Garai , Z., Brandeker , A., et al

    Szab \'o , G. M., Garai , Z., Brandeker , A., et al. 2022, , 659, L7

    2022

  61. [69]

    A., Gregory , S

    Vidotto , A. A., Gregory , S. G., Jardine , M., et al. 2014, , 441, 2361

    2014

  62. [70]

    A., Jardine , M., Morin , J., et al

    Vidotto , A. A., Jardine , M., Morin , J., et al. 2013, , 557, A67

    2013

  63. [71]

    C., Berta-Thompson , Z

    Waalkes , W. C., Berta-Thompson , Z. K., Newton , E. R., et al. 2024, , 962, 97

    2024

  64. [72]

    M., Plavchan , P

    Wittrock , J. M., Plavchan , P. P., Cale , B. L., et al. 2023, , 166, 232

    2023

  65. [73]

    J., Newton , E

    Wright , N. J., Newton , E. R., Williams , P. K. G., Drake , J. J., & Yadav , R. K. 2018, , 479, 2351

    2018

  66. [74]

    K., Christensen , U

    Yadav , R. K., Christensen , U. R., Morin , J., et al. 2015, , 813, L31

    2015

  67. [75]

    2025, , 536, 2046

    Yu , H., Garai , Z., Cretignier , M., et al. 2025, , 536, 2046

    2025

  68. [76]

    2022, , 512, 3060

    Zicher , N., Barrag \'a n , O., Klein , B., et al. 2022, , 512, 3060

    2022

  69. [77]

    , " * write output.state after.block = add.period write newline

    ENTRY address archiveprefix author booktitle chapter edition editor howpublished institution eprint journal key month note number organization pages publisher school series title type volume year label extra.label sort.label short.list INTEGERS output.state before.all mid.sent...

  70. [78]

    write newline

    " write newline "" before.all 'output.state := FUNCTION n.dashify 't := "" t empty not t #1 #1 substring "-" = t #1 #2 substring "--" = not "--" * t #2 global.max substring 't := t #1 #1 substring "-" = "-" * t #2 global.max substring 't := while if t #1 #1 substring * t #2 gl...

Pith tools

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