Pith. sign in

REVIEW 2 major objections 6 minor 98 references

Inactive longitude and superflare in the active single-lined pre-main sequence binary V2279 Cyg

T0 review · 2 major / 6 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 V2279 Cyg's flares skip one orbital phase for four years

desk verdict Solid observational study of a PMS binary, but the 'inactive longitude' claim rests on a post-hoc interval; the correct p-value is about 1%, not <0.03%, and the TESS superflare inside the gap muddies the picture. read the letter →

arxiv 2507.11066 v1 pith:AVG5FFZL submitted 2025-07-15 astro-ph.SR

Xueying Hu , Tianqi Cang , Jian-Ning Fu , Xuan Wang , Keyu Xing , Haotian Wang , Pascal Petit , Jiaxin Wang
show 2 more authors
Yong Yang He Zhao
This is my paper · ORCID
classification astro-ph.SR
keywords pre-main-sequencestarsbinarystellarflaresstarspotsactivelongitudestidalinteractionsTTauriV2279Cyg
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

V2279 Cyg is a young, tidally locked pair of stars still settling onto the main sequence, and its magnetic activity is not spread evenly around the star: starspots and strong hydrogen emission stay anchored near one orbital phase, while flares avoid a fixed stretch of the orbit. Over four years of Kepler photometry, 43 flares were recorded and none appeared in the phase window 0.60–0.78, a gap the authors calculate would occur by chance in fewer than 3 in 10,000 random distributions. They call this a first detection of an 'inactive longitude' of flares in an active binary, evidence that tidal forces between the two stars shape the magnetic geometry itself. If the claim holds, flare behavior in synchronized binaries becomes partly predictable from orbital phase, with direct implications for the environments of young planets. The same study finds a TESS superflare ($2.5\times10^{37}$ erg) inside the empty window, showing the suppressed zone does not block the most extreme events.

What carries the argument

The machinery that carries the argument is the orbital ephemeris: with a 4.1264-day period and near-zero eccentricity, the binary is synchronized, so rotational phase equals orbital phase and every flare, spot, or emission feature can be assigned a permanent longitude. On top of this phase grid, the authors stack the Kepler flare catalog of 43 events and the TESS catalog of 10 events (including the superflare), and they test the phase distribution of flares for empty stretches; the inactive longitude is the 0.18-wide interval that came out empty. The spot and prominence pictures come from a two-spot photometric model of the light curve, line-profile deconvolution to detect surface brightness asymmetries, and Doppler tomography of the H$\alpha$ emission, all tied to the same ephemeris.

What would settle it

The claim would be falsified by a single ordinary flare from V2279 Cyg recorded inside orbital phases 0.60–0.78 in continued high-cadence monitoring, since the suppression is supposed to persist; alternatively, recomputing the false-alarm probability for the largest empty gap among 43 random phases on a circle rather than for a pre-specified interval would show the deficit is about one percent, not below 0.03%.

Watch

Extended reading notes

Core claim

The central discovery, stated on the authors' terms, is that V2279 Cyg exhibits a longitudinally organized magnetic activity pattern with two complementary features: an active longitude where spots, H$\alpha$ emission, and most flares gather near phase 0.5, and an inactive longitude between phases 0.60 and 0.78 where no Kepler flare was detected in four years. They compute that, under a random distribution of the 43 Kepler flares, an empty interval of that width has a probability below 0.03%, and they designate this as the first inactive longitude identified in an active binary system. The same analysis yields a two-spot geometry with a large polar spot complex facing the companion, a Doppler-tomography map placing slingshot prominences near the inferior conjunction, and the detection of a white-light superflare with bolometric energy $2.5\times10^{37}$ erg in TESS data.

Load-bearing premise

The result depends on treating the empty phase window 0.60–0.78 as if it were chosen before looking at the data, when it was in fact selected because the flares avoided it; with the largest-gap correction the probability rises to about one percent, and the TESS superflare later landed inside the same window.

Editorial extensions

If this is right

  • If the inactive longitude is real, synchronized pre-main-sequence binaries can have longitude-locked flare suppression zones, and flare predictions for these systems should fold in orbital phase.
  • The persistent active longitude facing the secondary supports models in which tidal forces anchor magnetic flux tubes in the primary's convective envelope.
  • The superflare occurring inside the inactive window means the zone suppresses ordinary flares but does not forbid extreme ones, so the underlying magnetic topology retains strong free energy.
  • The estimated prominence mass-loss rate (about $10^{19}$ kg/yr) matches the X-ray-based wind estimate, implying prominence eruptions are a major wind channel in this system.
  • The existing TESS flare phases already include one superflare inside the Kepler-era inactive window, so the zone's persistence across activity levels is directly testable with published data.

Reading between the lines

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

  • Because the phase interval was chosen after seeing the empty gap, the quoted <0.03% probability is an overstatement; a largest-gap significance calculation would yield about 1%, so the inactive longitude is currently a suggestive pattern, not a confirmed structure.
  • The TESS superflare inside the interval (2019) shows the 'forbidden' zone is not absolutely flare-free; continued monitoring could reveal whether the suppression is permanent or a multi-year episode.
  • If the mechanism is tidal anchoring, the longitude of flare suppression should stay fixed relative to the companion over decades, distinguishing it from a drifting active longitude arising from differential rotation.
  • The same phase-stacking approach could be applied to other short-period synchronized binaries (e.g., other PMS or RS CVn systems) to establish whether inactive longitudes are a general tidal signature or an anomaly of this system.
Share X Bluesky LinkedIn Reddit HN

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 analyzes Kepler and TESS photometry together with LAMOST medium-resolution spectroscopy of V2279 Cyg, a single-lined pre-main-sequence binary, and derives stellar/orbital parameters, a two-spot model of the primary, the longitudinal distribution of spots and flares, H-alpha emission properties, a Doppler-tomographic prominence map, and flare energies including a TESS white-light superflare. The central new claim is an 'inactive longitude' of flares: no Kepler flare was detected in the orbital phase interval 0.60-0.78 over four years, with a quoted probability of <0.03% under random occurrence, and the paper presents this as the first such identification in an active binary system. The paper also reports a 2.5e37 erg superflare in TESS and estimates significant prominence-related mass loss.

Significance. If the inactive-longitude claim were statistically robust, it would be a valuable and novel constraint on how tidal synchronization shapes the magnetic geometry and flare occurrence in a PMS binary, especially in contrast to systems like DQ Tau and CM Dra that show no phase preference. The paper brings together a rich multi-instrument dataset and includes useful independent checks, notably the -0.78 correlation between H-alpha equivalent width and the phase-folded light curve, and the LSD-based detection of surface asymmetries. However, the headline claim is presently supported by a statistical test that does not account for post-hoc interval selection and is contradicted in part by the TESS superflare falling inside the same phase range. The underlying observations and modeling are valuable, but the paper's central discovery claim needs to be re-derived and reframed before it can be accepted.

major comments (2)
  1. [Section 4.2, Fig. 5] The central statistical claim is not computed for the way the interval was actually chosen. The text states that with 43 Kepler flares, the probability of no flare in the phase interval 0.60-0.78 is <0.03%, which is the value of (1-0.18)^43. That formula is only valid if the interval 0.60-0.78 was specified before inspecting the flare phases. In this paper the interval was selected because it is the observed empty gap, so the correct null calculation is a scan statistic: the probability that some interval of width 0.18 contains no flare under uniform random phases. The first-order scan statistic is approximately n(1-w)^(n-1) ≈ 1% for n=43 and w=0.18, an order of magnitude larger than the quoted value and nowhere near the <0.03% claimed. The authors should quote the corrected p-value, or better, perform an interval-free uniformity test such as a Rayleigh or Kuiper test, and should not present the pre-specified-interval probability as the evidence. This is load-bearing because the abstract, Section 5.2, and the conclusion all use this number to support the 'inactive longitude' and 'first such identification' claims. In addition, the abstract's phrase 'significantly reduced after the superior conjunction' is not directly supported by an empty-interval test; a comparison of flare rates before and after superior conjunction is needed.
  2. [Section 5.2 and Appendix D] The inactive-longitude interpretation is also weakened by the TESS superflare. Section 4.2 and Fig. 5 show that the TESS superflare in Sector 14 (Table 4, E = 2.53e37 erg) occurred inside the same phase range 0.60-0.78, and Section 5.2 acknowledges that 'the gap of normal flares shares almost the same phase as the only observed superflare.' An interval that contains a superflare cannot be described as persistently inactive without an explicit epoch-dependent qualification. Furthermore, Section 5.2 itself states that 'the number of flares is still small for a solid statistic,' an internal limitation that directly contradicts the strength of the abstract's claim. The authors should restrict the inactive-longitude claim to Kepler-era normal flares with the corrected p-value, or alternatively present an explicitly epoch-dependent interpretation that explains why the superflare does not count as activity in that longitude. The current wording overstates the significance of the finding.
minor comments (6)
  1. [Section 2] There are encoding artifacts in the text, such as 'Sectors 40 ? 41', '390?740 nm', and 'star?s'; these should be corrected to proper dashes and apostrophes.
  2. [Appendix B] The sentence 'Table 2 lists the radial velocities...' should refer to Table 3 in Appendix B, which actually contains the radial velocities and equivalent widths.
  3. [Section 4.3] The Pearson correlation of -0.78 is computed between H-alpha equivalent widths from LAMOST (2018-2020) and the average phase-folded Kepler light curve (2009-2013). Since spot evolution is acknowledged in the paper, the comparison should either use contemporaneous TESS photometry or explicitly caveat the epoch mismatch.
  4. [Section 4.1] The two-spot model is described as a toy model with MCMC degeneracy, but no quantitative uncertainty is given for the spot center longitude. Reporting a posterior interval for the spot phase would make the active-longitude claim easier to evaluate.
  5. [Section 5.3] There is a typo 'agreemen t' in the first paragraph of Section 5.3 that should be corrected.
  6. [Appendix D, Table 4] The flare table should clarify the time system used for TESS data (converted BKJD versus native TESS timestamps) so that the phase assignments can be reproduced exactly.

Circularity Check

1 steps flagged · score 4.0 of 10

Inactive-longitude significance is computed for a data-selected interval, making that step partially circular; the rest of the analysis is self-contained.

  1. fitted input called prediction [Section 4.2 (Longitude preference of flares), around Fig. 5; see also Section 5.2]
    "As shown in the phase-folded flare energy distribution in Fig. 5, NO flare was detected in the Kepler data within the phase range of 0.60 to 0.78, except a superflare observed in TESS Sector 14 and covered almost the gap. Assuming that the occurrence of flares is generally random, the 43 Kepler flares indicate a likelihood of <0.03% that no flare would be detected within a 0.18 phase interval during continuous monitoring."

    The interval 0.60-0.78 is not a pre-specified null region; it is the empty gap read off the same Kepler flare-phase distribution that provides the 43 flares used in the test. The quoted <0.03% is the fixed-window probability (1-0.18)^43. Because the window was chosen because it contains zero flares, the tested event is fixed by the data selection, so this is not a valid significance for a data-defined 'inactive longitude'; under a largest-gap or scan null the p-value is of order 1%. The interval location is effectively a fitted parameter derived from the data, and the claim of a significantly reduced flare frequency is forced by that construction.

full rationale

The paper is primarily an observational study and does not derive a prediction from a fitted model. The spot active longitude is read directly from the phase of the light-curve minimum and is independently supported by the H-alpha EW correlation (-0.78) and by LSD line-profile asymmetries. The PHOEBE two-spot model is explicitly labelled a toy model and is not used as a predictive result. The Doppler prominence reconstruction is a forward model with stated assumptions and is not circular. The cited Kepler flare catalogue (Oláh et al. 2021, 2022) is external, and the TESS flare tool (Xing et al. 2024, a co-author paper) is a published code-based method that does not import the target conclusion. The one genuinely circular step is in Section 4.2: the phase interval defining the 'inactive longitude' is selected from the observed gap in the same flare-phase data that is then used to compute its significance. The paper itself cautions that 'the number of flares is still small for a solid statistic' in Section 5.2 and notes that the TESS superflare falls in the same phase interval, so the central claim is not robust. Still, the underlying observations (the empty gap, spot phase, H-alpha correlation) remain independent measurements; therefore the circularity is partial rather than total.

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

The central claim depends on a handful of fitted/selected values: the phase interval boundaries (post hoc), the stellar masses and inclination (from evolutionary tracks and v sin i), and the two-spot model parameters (acknowledged toy model). The null hypothesis of random flare phase occurrence and the assumption of phase-independent flare detectability are domain assumptions that the inactive-longitude detection relies on. No new physical entities are introduced; the 'inactive longitude' is a statistical label, not a separate object.

free parameters (5)
  • Flare-free phase interval boundaries = 0.60 and 0.78
    The boundaries of the 'inactive longitude' are selected from the observed flare phase distribution because that is the empty gap (Section 4.2). This post-hoc selection is not accounted for in the quoted <0.03% probability.
  • Primary mass M1 = 0.86 ± 0.12 M⊙
    Derived by matching Teff and logg to MIST evolutionary tracks (Section 3). Used in the binary mass function to infer M2 and the masses. This mass also enters the flare energy scales.
  • Inclination i = 75°
    Computed from vsini = 43.2 km/s, radius R1 = 3.64 R⊙, and Prot = 4.1264 d (Section 3). Assumed fixed; affects the geometry of spot and prominence maps.
  • Two-spot model parameters = not fully listed in text; corner plot in Fig. 11
    PHOEBE MCMC fit to the Kepler Q1 light curve (Section 4.1). The authors themselves label it a 'toy model' with multiple local minima, so the spot parameters are not uniquely determined.
  • Gaussian FWHM for Hα local profile in tomography = ~15 km/s
    Chosen for Doppler tomography reconstruction (Section 4.3); affects the prominence map.
assumptions (6)
  • domain assumption The Kepler and TESS light curve modulation is caused by star spots (rotational modulation), not by other variability.
    Used throughout; supported by previous studies of V2279 Cyg (Szabó et al. 2011; Oláh et al. 2021), and the phase-stable light curve minimum.
  • domain assumption Under the null hypothesis, flare occurrence is random in orbital/rotational phase.
    Section 4.2: 'Assuming that the occurrence of flares is generally random'. This defines the statistical test for the inactive longitude.
  • domain assumption The Hα emission originates from optically thin, co-rotating prominence material (slingshot prominences), not from accretion.
    Section 4.3: 'we attribute the Hα emission of V2279 Cyg to the chromospheric activity due to the ultraviolet excess and no significant infrared excess in SED'. The tomography assumes optically thin gas in quasi-steady corotation.
  • domain assumption MIST/MESA evolutionary tracks are accurate for PMS stars of this metallicity.
    Section 3: used to derive age and mass from Teff, logg, and MG.
  • domain assumption The binary orbit is circular (e=0) and synchronized with rotation.
    Section 3: fixed values; used in the mass function and in interpreting longitudes fixed in the rotating frame.
  • domain assumption Flare detection from Kepler (by Oláh et al. 2021, 2022) and TESS (Xing et al. 2024) is complete and unbiased with respect to orbital phase.
    Section 4.2: the 43 Kepler flares are taken from the literature; any phase-dependent detection efficiency would mimic an inactive longitude.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Inactive longitude and superflare in the active single-lined pre-main sequence binary V2279 Cyg." pith.science (2026). https://pith.science/paper/AVG5FFZL

@misc{pith2026250711066,
  author       = {Pith},
  title        = {Pith review of: Inactive longitude and superflare in the active single-lined pre-main sequence binary V2279 Cyg},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/AVG5FFZL}},
  note         = {Machine review of arXiv:2507.11066}
}
abstract

Young, solar-like stars in the pre-main sequence (PMS) stage exhibit vigorous magnetic activity that significantly influences their circumstellar environments and the processes of planetary formation and evolution. In binary systems, tidal forces and magnetic interactions can further shape the magnetic geometry. We report a longitudinal preference of star spots, chromospheric activities, and flares in the active single-lined spectroscopic PMS binary system V2279 Cyg, based on long-term photometric observations from \textit{Kepler} and \textit{TESS} alongside spectroscopic data from LAMOST. The system is classified as a weak-line T Tauri binary, with component masses estimated at 0.86 $M_\odot$ and 0.27 $M_\odot$. V2279 Cyg's nearly circular orbit is synchronized with its 4.126-day rotational period. Observations reveal large star spot regions clustered near the far-side hemisphere. Spectroscopic data show strong, double-peak H$\alpha$ emission, the strength of which is highly correlated with star spot distribution, indicating the presence of an active longitude on the primary star. We also mapped the prominence structure co-rotating with the primary star, suggesting a dense structure close to the near-side hemisphere. Furthermore, we identify an inactive longitude of flares during the 4-year \textit{Kepler} observations, where the frequency of flare activity is significantly reduced after the superior conjunction, marking the first such identification in active binary systems. Additionally, a white light superflare, releasing energy of $2.5 \times 10^{37}$ erg, was detected in \textit{TESS} observations. These findings provide valuable insights into the magnetic field geometry and dynamo processes in PMS binaries, underscoring the critical role of tidal interactions in shaping magnetic activities.

Figures

Figures reproduced from arXiv: 2507.11066 by the authors.

Figure 1
Figure 1. The phase-folded curves for V2279 Cyg. (a) Kepler light curve. The red dots mark the minimum value in each cycle. (b) TESS light curve. The red dots mark the minimum value in each cycle. (c) The equivalent widths (EWs) of Hα line for V2279 Cyg from LAMOST MRS. The colorbar for (a-c) represents the Barycentric Kepler Julian Date (BKJD). (d) RV curves of V2279 Cyg, where the red dots represent the RVs measured from th… view at source ↗
Figure 2
Figure 2. Evolutionary tracks from MIST with input masses between 0.6 and 1 M⊙ (step: 0.05 M⊙) and [Fe/H] of -0.5. The red star marks the position of the primary component with error bars. The black dotted lines are isochrones. inclination angle of i ∼ 75◦ . Thus the mass of the secondary component is M2 = 0.27 M⊙, and the radius of the orbit Rorb = 11.3 R⊙. Since the more massive component does not reach the main sequence, t… view at source ↗
Figure 3
Figure 3. Difference between LSD profiles and the Gaussian fitting (gray horizontal lines) of the mean LSD profile. The vertical gray dashed lines mark the ±v sin i. Uncertainties (vertical blue lines) are estimated with the LSD process from the observational uncertainty. Assuming fixed orbital parameters for the V2279 Cyg binary system as described in Sect. 3, we modeled the star spots on the surface of the primary component… view at source ↗
Figures from the paper (13 more)
Figure 4
Figure 4. Figure 4: The spot model to fit the light curve of Kepler Q1 data set. (a) The normalized flux in the phase-folded diagram for the model (blue line) and observations (black dot). (b-d) The configurations of the two-spot model at ϕ=0, 0.35 and 0.7, respectively. The view illustra…
Figure 5
Figure 5. Figure 5: The phase-folded flare energies calculated from Kepler LC light curves (Ol´ah et al. 2022) and TESS (our work). The red dots mark the Kepler results (at the peak time), and the blue lines represent the TESS results (labeling the duration). The light red histogram displ…
Figure 6
Figure 6. Figure 6: Dynamic spectra showing the Hα line of V2279 Cyg (in 2020). From left to right: observations (after correcting the rv caused by the binary system), model and model residual. The vertical black dashed lines mark the ±vsini. 5. DISCUSSION 5.1. Evolutionary state of V2279…
Figure 7
Figure 7. Figure 7: Prominence map (2020). The positions and relative sizes of the primary and secondary stars are marked with filled and dotted blue circles. The dotted black lines indicate the Roche lobe. The short black lines mark the observation phases. The color scale represents the …
Figure 8
Figure 8. Figure 8: The logarithmic fractional X-ray luminosity log(LX/Lbol) vs. rotational period for V2279 Cyg, comparing with h Per members (circles) of different mass (Argiroffi et al. 2016), and MS stars (squares) in the unsaturated and saturated regime from Vidotto et al. (2014). Th…
Figure 9
Figure 9. Figure 9: Kepler LC light curve (upper) and its power spectrum (lower). The red dot in the lower panel marks the main frequency and the blue dot marks its harmonic [PITH_FULL_IMAGE:figures/full_fig_p014_9.png]
Figure 10
Figure 10. Figure 10: Sliding Lomb?Scargle periodogram (sLSP) for the Kepler LC light curve. The red line marks the maximum frequency value [PITH_FULL_IMAGE:figures/full_fig_p014_10.png]
Figure 11
Figure 11. Figure 11: Corner map of the MCMC fitting result. The dashed lines show the 1σ edges of the MCMC results [PITH_FULL_IMAGE:figures/full_fig_p017_11.png]
Figure 12
Figure 12. Figure 12: The superflare in TESS Sector 14 [PITH_FULL_IMAGE:figures/full_fig_p018_12.png]
Figure 13
Figure 13. Figure 13: The corresponding cumulative flare frequency distribution (FFD) of Kepler (blue) and TESS (green) flares. The α parameters of Eq.D1 fitting are shown with red lines [PITH_FULL_IMAGE:figures/full_fig_p019_13.png]
Figure 14
Figure 14. Figure 14: SED of V2279 Cyg. The template spectra is from Coelho (2014), with Teff = 4500 K, log g = 3, [Fe/H] = -0.5, [α/Fe] = 0. The SED data were from VizieR (Ochsenbein 1996) [PITH_FULL_IMAGE:figures/full_fig_p020_14.png]
Figure 15
Figure 15. Figure 15: LSD profiles (blue lines with error bars) arranged by phase, spanning from 2018 to 2020. The gray lines represent the mean photospheric structures modeled using Gaussian profiles. Black circles indicate the minimum value of each profile. The vertical black dashed line…
Figure 16
Figure 16. Figure 16: Hα profiles averaged over individual nights during 2018-2020 (from left to right), after correcting the RV caused by the binary system. BJD0 = 2458268.3132 was chosen as the initial time for phase-folding. Two vertical dashed lines show the ±vsini (Frasca et al. 2022)…

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

98 extracted references · 20 canonical work pages

  1. [1]

    2000, AJ, 119, 1901, doi: 10.1086/301321

    Akerlof, C., Amrose, S., Balsano, R., et al. 2000, AJ, 119, 1901, doi: 10.1086/301321

    doi:10.1086/301321 2000

  2. [2]

    L., Jensen, E

    Akeson, R. L., Jensen, E. L., Carpenter, J., et al. 2019, The Astrophysical Journal, 872, 158

    2019

  3. [3]

    2016, A&A, 589, A113, doi: 10.1051/0004-6361/201526539 Astropy Collaboration, Robitaille, T

    Argiroffi, C., Caramazza, M., Micela, G., et al. 2016, A&A, 589, A113, doi: 10.1051/0004-6361/201526539 Astropy Collaboration, Robitaille, T. P., Tollerud, E. J., et al. 2013, A&A, 558, A33, doi: 10.1051/0004-6361/201322068 Astropy Collaboration, Price-Whelan, A. M., Sip˝ ocz, B. M., et al. 2018, AJ, 156, 123, doi: 10.3847/1538-3881/aabc4f Astropy Collabo...

    doi:10.1051/0004-6361/201526539 2016

  4. [4]

    Berdyugina, S. V. 2005, Living Reviews in Solar Physics, 2, 8, doi: 10.12942/lrsp-2005-8

    doi:10.12942/lrsp-2005-8 2005

  5. [5]

    Fekel, F. C. 1998, A&A, 334, 863

    1998

  6. [6]

    A., Huber, D., van Saders, J

    Berger, T. A., Huber, D., van Saders, J. L., et al. 2020, AJ, 159, 280, doi: 10.3847/1538-3881/159/6/280

    doi:10.3847/1538-3881/159/6/280 2020

  7. [7]

    Q., Petit, P., Donati, J

    Cang, T. Q., Petit, P., Donati, J. F., & Folsom, C. P. 2021, A&A, 654, A42, doi: 10.1051/0004-6361/202141975

    work page doi:10.1051/0004-6361/202141975 2021

  8. [8]

    Q., Petit, P., Donati, J

    Cang, T. Q., Petit, P., Donati, J. F., et al. 2020, A&A, 643, A39, doi: 10.1051/0004-6361/202037693

    doi:10.1051/0004-6361/202037693 2020

Show all 98 references
  1. [9]

    A., Strassmeier, K

    Carroll, T. A., Strassmeier, K. G., Rice, J. B., & K¨ unstler, A. 2012, A&A, 548, A95, doi: 10.1051/0004-6361/201220215

    2012 doi

  2. [10]

    2016, ApJ, 823, 102, doi: 10.3847/0004-637X/823/2/102

    Choi, J., Dotter, A., Conroy, C., et al. 2016, ApJ, 823, 102, doi: 10.3847/0004-637X/823/2/102

    2016 doi

  3. [11]

    Coelho, P. R. T. 2014, MNRAS, 440, 1027, doi: 10.1093/mnras/stu365 Collier Cameron, A. 1996, in IAU Symposium, Vol. 176, Stellar Surface Structure, ed. K. G. Strassmeier & J. L. Linsky, 449

    2014 doi

  4. [12]

    E., Kochoska, A., Hey, D., et al

    Conroy, K. E., Kochoska, A., Hey, D., et al. 2020, ApJS, 250, 34, doi: 10.3847/1538-4365/abb4e2

    2020 doi

  5. [13]

    L., Sordo, R., Pailler, F., et al

    Creevey, O. L., Sordo, R., Pailler, F., et al. 2023, A&A, 674, A26, doi: 10.1051/0004-6361/202243688

    2023 doi

  6. [14]

    2000, Information Bulletin on Variable Stars, 4898, 1

    Dahlmark, L. 2000, Information Bulletin on Variable Stars, 4898, 1

    2000

  7. [15]

    M., & Johnston, C

    Daley-Yates, S., Jardine, M. M., & Johnston, C. D. 2023, MNRAS, 526, 1646, doi: 10.1093/mnras/stad2752 De Cat, P., Fu, J. N., Ren, A. B., et al. 2015, ApJS, 220, 19, doi: 10.1088/0067-0049/220/1/19

    2023 doi

  8. [16]

    E., Bailer-Jones, C

    Dharmawardena, T. E., Bailer-Jones, C. A. L., Fouesneau, M., et al. 2024, MNRAS, doi: 10.1093/mnras/stae1474

    2024 doi

  9. [17]

    F., Mengel, M., Carter, B

    Donati, J. F., Mengel, M., Carter, B. D., et al. 2000, MNRAS, 316, 699, doi: 10.1046/j.1365-8711.2000.03570.x 22 Figure 16.Hαprofiles averaged over individual nights during 2018-2020 (from left to right), after correcting the R V caused by the binary system. BJD 0 = 2458268.31...

    2000

  10. [18]

    F., Semel, M., Carter, B

    Donati, J. F., Semel, M., Carter, B. D., Rees, D. E., & Collier Cameron, A. 1997, MNRAS, 291, 658, doi: 10.1093/mnras/291.4.658

    1997 doi

  11. [19]

    F., H´ ebrard, E., Hussain, G

    Donati, J. F., H´ ebrard, E., Hussain, G. A. J., et al. 2015, MNRAS, 453, 3706, doi: 10.1093/mnras/stv1837

    2015 doi

  12. [20]

    2016, ApJS, 222, 8, doi: 10.3847/0067-0049/222/1/8

    Dotter, A. 2016, ApJS, 222, 8, doi: 10.3847/0067-0049/222/1/8

    2016 doi

  13. [21]

    A., Page, K

    Evans, P. A., Page, K. L., Osborne, J. P., et al. 2020, ApJS, 247, 54, doi: 10.3847/1538-4365/ab7db9 Fern´ andez, M., Stelzer, B., Henden, A., et al. 2004, A&A, 427, 263, doi: 10.1051/0004-6361:20034463

    2020 doi

  14. [22]

    F., Grankin, K., et al

    Finociety, B., Donati, J. F., Grankin, K., et al. 2023, MNRAS, 520, 3049, doi: 10.1093/mnras/stad267

    2023 doi

  15. [23]

    P., Barnes, R., Davenport, J

    Fleming, D. P., Barnes, R., Davenport, J. R. A., & Luger, R. 2019, ApJ, 881, 88, doi: 10.3847/1538-4357/ab2ed2

    2019 doi

  16. [24]

    P., Bouvier, J., Petit, P., et al

    Folsom, C. P., Bouvier, J., Petit, P., et al. 2018, MNRAS, 474, 4956, doi: 10.1093/mnras/stx3021

    2018 doi

  17. [25]

    W., Lang, D., & Goodman, J

    Foreman-Mackey, D., Hogg, D. W., Lang, D., & Goodman, J. 2013, PASP, 125, 306, doi: 10.1086/670067

    2013 doi

  18. [26]

    2016, A&A, 594, A39, doi: 10.1051/0004-6361/201628337

    Frasca, A., Molenda- ˙Zakowicz, J., De Cat, P., et al. 2016, A&A, 594, A39, doi: 10.1051/0004-6361/201628337

    2016 doi

  19. [27]

    2022, A&A, 664, A78, doi: 10.1051/0004-6361/202243268

    Frasca, A., Molenda- ˙Zakowicz, J., Alonso-Santiago, J., et al. 2022, A&A, 664, A78, doi: 10.1051/0004-6361/202243268

    2022 doi

  20. [28]

    D., Zong, W., et al

    Fu, J.-N., Cat, P. D., Zong, W., et al. 2020, Research in Astronomy and Astrophysics, 20, 167, doi: 10.1088/1674-4527/20/10/167 Gaia Collaboration. 2020, VizieR Online Data Catalog: Gaia EDR3 (Gaia Collaboration, 2020), VizieR On-line Data Catalog: I/350. Originally published ...

    2020 doi

  21. [29]

    2013, A&A, 556, A36, doi: 10.1051/0004-6361/201321302

    Gallet, F., & Bouvier, J. 2013, A&A, 556, A36, doi: 10.1051/0004-6361/201321302

    2013 doi

  22. [30]

    2017, A&A, 597, A14, doi: 10.1051/0004-6361/201629034

    Gallet, F., Charbonnel, C., Amard, L., et al. 2017, A&A, 597, A14, doi: 10.1051/0004-6361/201629034

    2017 doi

  23. [31]

    K., et al

    Guerrero, G., Zaire, B., Smolarkiewicz, P. K., et al. 2019, ApJ, 880, 6, doi: 10.3847/1538-4357/ab224a

    2019 doi

  24. [32]

    G., Mitrou, C

    Gunn, A. G., Mitrou, C. K., & Doyle, J. G. 1998, MNRAS, 296, 150, doi: 10.1046/j.1365-8711.1998.01347.x 23

    1998

  25. [33]

    2016, ApJ, 818, 127, doi: 10.3847/0004-637X/818/2/127

    Gyenge, N., Ludm´ any, A., & Baranyi, T. 2016, ApJ, 818, 127, doi: 10.3847/0004-637X/818/2/127

    2016 doi

  26. [34]

    A., Folsom, C

    Hill, C. A., Folsom, C. P., Donati, J. F., et al. 2019, MNRAS, 484, 5810, doi: 10.1093/mnras/stz403

    2019 doi

  27. [35]

    2003a, A&A, 405, 291, doi: 10.1051/0004-6361:20030582 —

    Holzwarth, V., & Sch¨ ussler, M. 2003a, A&A, 405, 291, doi: 10.1051/0004-6361:20030582 —. 2003b, A&A, 405, 303, doi: 10.1051/0004-6361:20030584

    doi

  28. [36]

    E., Pablo, H., et al

    Horvat, M., Conroy, K. E., Pablo, H., et al. 2018, ApJS, 237, 26, doi: 10.3847/1538-4365/aacd0f

    2018 doi

  29. [37]

    X., Vanderburg, A., P´ al, A., et al

    Huang, C. X., Vanderburg, A., P´ al, A., et al. 2020a, Research Notes of the American Astronomical Society, 4, 204, doi: 10.3847/2515-5172/abca2e —. 2020b, Research Notes of the American Astronomical Society, 4, 206, doi: 10.3847/2515-5172/abca2d

    doi

  30. [38]

    C., Ip, W

    Huang, L. C., Ip, W. H., Lin, C. L., et al. 2020c, ApJ, 892, 58, doi: 10.3847/1538-4357/ab774a

    doi

  31. [39]

    Hussain, G. A. J., & Alecian, E. 2014, in IAU Symposium, Vol. 302, Magnetic Fields throughout Stellar Evolution, ed. P. Petit, M. Jardine, & H. C. Spruit, 25–37, doi: 10.1017/S1743921314001653

    2014 doi

  32. [40]

    2001, A&A, 365, L1, doi: 10.1051/0004-6361:20000036

    Jansen, F., Lumb, D., Altieri, B., et al. 2001, A&A, 365, L1, doi: 10.1051/0004-6361:20000036

    2001 doi

  33. [41]

    Jeffers, S. V. 2005, MNRAS, 359, 729, doi: 10.1111/j.1365-2966.2005.08951.x

    2005

  34. [42]

    P., & G¨ udel, M

    Johnstone, C. P., & G¨ udel, M. 2015, A&A, 578, A129, doi: 10.1051/0004-6361/201425283

    2015 doi

  35. [43]

    P., Pilat-Lohinger, E., L¨ uftinger, T., G¨ udel, M., & St¨ okl, A

    Johnstone, C. P., Pilat-Lohinger, E., L¨ uftinger, T., G¨ udel, M., & St¨ okl, A. 2019, A&A, 626, A22, doi: 10.1051/0004-6361/201832805

    2019 doi

  36. [44]

    E., Horvat, M., et al

    Jones, D., Conroy, K. E., Horvat, M., et al. 2020, ApJS, 247, 63, doi: 10.3847/1538-4365/ab7927

    2020 doi

  37. [45]

    G., Borucki, W

    Koch, D. G., Borucki, W. J., Basri, G., et al. 2010, ApJL, 713, L79, doi: 10.1088/2041-8205/713/2/L79 K´ osp´ al,´A., ´Abrah´ am, P., Zsidi, G., et al. 2018, ApJ, 862, 44, doi: 10.3847/1538-4357/aacafa

    2010 doi

  38. [46]

    Kowalski, A. F. 2024, Living Reviews in Solar Physics, 21, 1, doi: 10.1007/s41116-024-00039-4

    2024 doi

  39. [47]

    2022, Research Notes of the American Astronomical Society, 6, 236, doi: 10.3847/2515-5172/aca158

    Kunimoto, M., Tey, E., Fong, W., et al. 2022, Research Notes of the American Astronomical Society, 6, 236, doi: 10.3847/2515-5172/aca158

    2022 doi

  40. [48]

    2021, Research Notes of the American Astronomical Society, 5, 234, doi: 10.3847/2515-5172/ac2ef0

    Kunimoto, M., Huang, C., Tey, E., et al. 2021, Research Notes of the American Astronomical Society, 5, 234, doi: 10.3847/2515-5172/ac2ef0

    2021 doi

  41. [49]

    A., Stempels, H

    Kupka, F., Piskunov, N., Ryabchikova, T. A., Stempels, H. C., & Weiss, W. W. 1999, A&AS, 138, 119, doi: 10.1051/aas:1999267

    1999 doi

  42. [50]

    H., Moffett, T

    Lacy, C. H., Moffett, T. J., & Evans, D. S. 1976, ApJS, 30, 85, doi: 10.1086/190358

    1976 doi

  43. [51]

    F., Flaccomio, E., Messina, S., et al

    Lanza, A. F., Flaccomio, E., Messina, S., et al. 2016, A&A, 592, A140, doi: 10.1051/0004-6361/201628382

    2016 doi

  44. [52]

    W., & Bovy, J

    Leung, H. W., & Bovy, J. 2019, MNRAS, 483, 3255, doi: 10.1093/mnras/sty3217

    2019 doi

  45. [53]

    2023, Universe, 9, 364, doi: 10.3390/universe9080364

    Li, J., & Chen, X. 2023, Universe, 9, 364, doi: 10.3390/universe9080364

    2023 doi

  46. [54]

    D., et al

    Li, J., Tenenbaum, P., Twicken, J. D., et al. 2019, PASP, 131, 024506, doi: 10.1088/1538-3873/aaf44d Ma ´ ız Apell´ aniz, J. 2024, arXiv e-prints, arXiv:2401.01116, doi: 10.48550/arXiv.2401.01116

    2019 doi arXiv

  47. [55]

    R., Schiavon, R

    Majewski, S. R., Schiavon, R. P., Frinchaboy, P. M., et al. 2017, AJ, 154, 94, doi: 10.3847/1538-3881/aa784d

    2017 doi

  48. [56]

    E., Torres, G., Prsa, A., et al

    Mamajek, E. E., Torres, G., Prsa, A., et al. 2015, arXiv e-prints, arXiv:1510.06262, doi: 10.48550/arXiv.1510.06262

    2015 doi arXiv

  49. [57]

    R., & Horne, K

    Marsh, T. R., & Horne, K. 1988, MNRAS, 235, 269, doi: 10.1093/mnras/235.1.269

    1988 doi

  50. [58]

    V., Sethi, R., Armitage, T., et al

    Martin, D. V., Sethi, R., Armitage, T., et al. 2024, MNRAS, 528, 963, doi: 10.1093/mnras/stae015

    2024 doi

  51. [59]

    Mathieu, R. D. 1994, ARA&A, 32, 465, doi: 10.1146/annurev.aa.32.090194.002341

    1994

  52. [60]

    M., Brandenburg, A., & Tuominen, I

    Moss, D., Barker, D. M., Brandenburg, A., & Tuominen, I. 1995, A&A, 294, 155

    1995

  53. [61]

    1997, A&A, 321, 151

    Moss, D., & Tuominen, I. 1997, A&A, 321, 151

    1997

  54. [62]

    A., Hussain, G., Donati, J

    Nicholson, B. A., Hussain, G., Donati, J. F., et al. 2021, MNRAS, 504, 2461, doi: 10.1093/mnras/stab879

    2021 doi

  55. [63]

    A., Hussain, G

    Nicholson, B. A., Hussain, G. A. J., Donati, J. F., et al. 2018, MNRAS, 480, 1754, doi: 10.1093/mnras/sty1965

    2018 doi

  56. [64]

    1996, The VizieR database of astronomical catalogues, CDS, Centre de Donnes astronomiques de Strasbourg, doi: 10.26093/CDS/VIZIER

    Ochsenbein, F. 1996, The VizieR database of astronomical catalogues, CDS, Centre de Donnes astronomiques de Strasbourg, doi: 10.26093/CDS/VIZIER

    1996 doi

  57. [65]

    2000, A&AS, 143, 23, doi: 10.1051/aas:2000169 Ol´ ah, K

    Ochsenbein, F., Bauer, P., & Marcout, J. 2000, A&AS, 143, 23, doi: 10.1051/aas:2000169 Ol´ ah, K. 2006, Ap&SS, 304, 145, doi: 10.1007/s10509-006-9096-x Ol´ ah, K., K˝ ov´ ari, Z., G¨ unther, M. N., et al. 2021, A&A, 647, A62, doi: 10.1051/0004-6361/202039674 Ol´ ah, K., Seli, ...

    2000 doi

  58. [66]

    2011, ApJS, 192, 3, doi: 10.1088/0067-0049/192/1/3

    Paxton, B., Bildsten, L., Dotter, A., et al. 2011, ApJS, 192, 3, doi: 10.1088/0067-0049/192/1/3

    2011 doi

  59. [67]

    2013, ApJS, 208, 4, doi: 10.1088/0067-0049/208/1/4

    Paxton, B., Cantiello, M., Arras, P., et al. 2013, ApJS, 208, 4, doi: 10.1088/0067-0049/208/1/4

    2013 doi

  60. [68]

    2015, ApJS, 220, 15, doi: 10.1088/0067-0049/220/1/15 24

    Paxton, B., Marchant, P., Schwab, J., et al. 2015, ApJS, 220, 15, doi: 10.1088/0067-0049/220/1/15 24

    2015 doi

  61. [69]

    F., Jardine, M., & Collier Cameron, A

    Petit, P., Donati, J. F., Jardine, M., & Collier Cameron, A. 2005, in IAU Symposium, Vol. 226, Coronal and Stellar Mass Ejections, ed. K. Dere, J. Wang, & Y. Yan, 511–512, doi: 10.1017/S1743921305001158

    2005 doi

  62. [70]

    Pigulski, A., Pojma´ nski, G., Pilecki, B., & Szczygie l, D. M. 2009, AcA, 59, 33, doi: 10.48550/arXiv.0903.4921

    2009 doi arXiv

  63. [71]

    E., Kupka, F., Ryabchikova, T

    Piskunov, N. E., Kupka, F., Ryabchikova, T. A., Weiss, W. W., & Jeffery, C. S. 1995, A&AS, 112, 525 Prˇ sa, A., & Zwitter, T. 2005, ApJ, 628, 426, doi: 10.1086/430591 Prˇ sa, A., Conroy, K. E., Horvat, M., et al. 2016, ApJS, 227, 29, doi: 10.3847/1538-4365/227/2/29

    1995 doi

  64. [72]

    R., Winn, J

    Ricker, G. R., Winn, J. N., Vanderspek, R., et al. 2015, Journal of Astronomical Telescopes, Instruments, and Systems, 1, 014003, doi: 10.1117/1.JATIS.1.1.014003

    2015 doi

  65. [73]

    2000, ApJ, 540, 583, doi: 10.1086/309303

    Sammis, I., Tang, F., & Zirin, H. 2000, ApJ, 540, 583, doi: 10.1086/309303

    2000 doi

  66. [74]

    A., et al

    See, V., Jardine, M., Vidotto, A. A., et al. 2017, MNRAS, 466, 1542, doi: 10.1093/mnras/stw3094

    2017 doi

  67. [75]

    Sethi, R., & Martin, D. V. 2024, MNRAS, 529, 4442, doi: 10.1093/mnras/stae717

    2024 doi

  68. [76]

    Simonian, G. V. A., Pinsonneault, M. H., & Terndrup, D. M. 2019, ApJ, 871, 174, doi: 10.3847/1538-4357/aaf97c

    2019 doi

  69. [77]

    B., Donati, J

    Skelly, M. B., Donati, J. F., Bouvier, J., et al. 2010, MNRAS, 403, 159, doi: 10.1111/j.1365-2966.2009.16132.x

    2010

  70. [78]

    R., & Donati, J

    Steeghs, D., Horne, K., Marsh, T. R., & Donati, J. F. 1996, MNRAS, 281, 626, doi: 10.1093/mnras/281.2.626 Szab´ o, R., Szabados, L., Ngeow, C. C., et al. 2011, MNRAS, 413, 2709, doi: 10.1111/j.1365-2966.2011.18342.x

    1996

  71. [79]

    2019, ApJ, 879, 69, doi: 10.3847/1538-4357/ab2331

    Ting, Y.-S., Conroy, C., Rix, H.-W., & Cargile, P. 2019, ApJ, 879, 69, doi: 10.3847/1538-4357/ab2331

    2019 doi

  72. [80]

    2007, A&A, 461, 1057, doi: 10.1051/0004-6361:20065776

    Toledano, O., Moreno, E., Koenigsberger, G., Detmers, R., & Langer, N. 2007, A&A, 461, 1057, doi: 10.1051/0004-6361:20065776

    2007 doi

  73. [81]

    Vida, K., & Roettenbacher, R. M. 2018, A&A, 616, A163, doi: 10.1051/0004-6361/201833194

    2018 doi

  74. [82]

    Vidotto, A. A. 2021, Living Reviews in Solar Physics, 18, 3, doi: 10.1007/s41116-021-00029-w

    2021 doi

  75. [83]

    A., Gregory, S

    Vidotto, A. A., Gregory, S. G., Jardine, M., et al. 2014, MNRAS, 441, 2361, doi: 10.1093/mnras/stu728 Villarreal D’Angelo, C., Jardine, M., Johnstone, C. P., &

    2014 doi

  76. [84]

    2019, MNRAS, 485, 1448, doi: 10.1093/mnras/stz477

    See, V. 2019, MNRAS, 485, 1448, doi: 10.1093/mnras/stz477

    2019 doi

  77. [85]

    2020, AJ, 160, 252, doi: 10.3847/1538-3881/abbe20

    Vincent, O., Bergeron, P., & Lafreni` ere, D. 2020, AJ, 160, 252, doi: 10.3847/1538-3881/abbe20

    2020 doi

  78. [86]

    S., & Penrod, G

    Vogt, S. S., & Penrod, G. D. 1983, PASP, 95, 565, doi: 10.1086/131208

    1983 doi

  79. [87]

    2020, ApJS, 251, 27, doi: 10.3847/1538-4365/abc1ed

    Wang, J., Fu, J.-N., Zong, W., et al. 2020, ApJS, 251, 27, doi: 10.3847/1538-4365/abc1ed

    2020 doi

  80. [88]

    Waugh, R. F. P., Jardine, M. M., Morin, J., & Donati, J. F. 2021, MNRAS, 505, 5104, doi: 10.1093/mnras/stab1709

    2021 doi

  81. [89]

    2022, ApJ, 926, 40, doi: 10.3847/1538-4357/ac4755

    Wei, X. 2022, ApJ, 926, 40, doi: 10.3847/1538-4357/ac4755

    2022 doi

  82. [90]

    L., Eisenhardt, P

    Wright, E. L., Eisenhardt, P. R. M., Mainzer, A. K., et al. 2010, AJ, 140, 1868, doi: 10.1088/0004-6256/140/6/1868

    2010 doi

  83. [91]

    2014, in IAU Symposium, Vol

    Wu, Y., Du, B., Luo, A., Zhao, Y., & Yuan, H. 2014, in IAU Symposium, Vol. 306, Statistical Challenges in 21st Century Cosmology, ed. A. Heavens, J.-L. Starck, & A. Krone-Martins, 340–342, doi: 10.1017/S1743921314010825

    2014 doi

  84. [92]

    2024, ApJS, 271, 57, doi: 10.3847/1538-4365/ad2ddd

    Xing, K., Zong, W., Silvotti, R., et al. 2024, ApJS, 271, 57, doi: 10.3847/1538-4365/ad2ddd

    2024 doi

  85. [93]

    2021, MNRAS, 501, 1878, doi: 10.1093/mnras/staa3793

    Xu, F., Gu, S., & Ioannidis, P. 2021, MNRAS, 501, 1878, doi: 10.1093/mnras/staa3793

    2021 doi

  86. [94]

    P., & Bouchet, L

    Zahn, J. P., & Bouchet, L. 1989, A&A, 223, 112

    1989

  87. [95]

    F., & Klein, B

    Zaire, B., Donati, J. F., & Klein, B. 2021, MNRAS, 504, 1969, doi: 10.1093/mnras/stab1019 —. 2022, MNRAS, 513, 2893, doi: 10.1093/mnras/stac721

    2021 doi

  88. [96]

    2021, ApJS, 256, 14, doi: 10.3847/1538-4365/ac0834

    Zhang, B., Li, J., Yang, F., et al. 2021, ApJS, 256, 14, doi: 10.3847/1538-4365/ac0834

    2021 doi

  89. [97]

    2018a, ApJ, 853, 98, doi: 10.3847/1538-4357/aaa548

    Zong, W., Charpinet, S., Fu, J.-N., et al. 2018a, ApJ, 853, 98, doi: 10.3847/1538-4357/aaa548

    doi

  90. [98]

    2018b, ApJS, 238, 30, doi: 10.3847/1538-4365/aadf81 —

    Zong, W., Fu, J.-N., De Cat, P., et al. 2018b, ApJS, 238, 30, doi: 10.3847/1538-4365/aadf81 —. 2020, ApJS, 251, 15, doi: 10.3847/1538-4365/abbb2d

    2020 doi

Pith tools

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