Pith. sign in

REVIEW 4 minor 219 references

The intermediate rotation-period gap marks a real transition in chromospheric magnetic activity, not just photospheric spots.

Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →

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

T0 review · grok-4.5

2026-07-11 04:18 UTC pith:TMHKA7GB

load-bearing objection Solid multi-proxy confirmation that the intermediate-period gap imprints on chromospheric Ca II IRT for Kepler field stars, carefully hedged as "hints" and aligned with prior Sph results.

arxiv 2607.05651 v1 pith:TMHKA7GB submitted 2026-07-06 astro-ph.SR

Hints of enhanced magnetic activity after the intermediate rotation period gap as traced by the chromospheric Ca ii infrared triplet

Diego Godoy-Rivera , Savita Mathur , Tyler Richey-Yowell , Angela R. G. Santos , Rafael A. Garcia , Desmond H. Grossmann , Zachary R. Claytor , Paul G. Beck This is my paper
classification astro-ph.SR
keywords stellar activitystellar rotationchromospheresCa II infrared tripletintermediate-period gapKepler starsgyrochronologystellar multiplicity
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

Low-mass stars spin down as they age, and their magnetic activity usually declines with that spin-down. A sparsely populated gap at intermediate rotation periods, already known to produce a dip then a rise in photospheric activity, is here shown to leave the same signature in a chromospheric tracer: the Ca II infrared triplet measured by Gaia for Kepler field stars. After the gap, main-sequence stars again show elevated chromospheric emission, and the locations of the dip and subsequent peak line up with those previously found in the photometric Sph index, both in period and in Rossby number. Later spectral types are systematically more active at fixed period, and close binaries further elevate the upper envelope of activity among rapid rotators. The result implies that the gap is a genuine change in the star's magnetic engine felt from the photosphere into the chromosphere, and therefore must be folded into age diagnostics and models of planetary environments.

Core claim

For main-sequence Kepler stars, chromospheric magnetic activity traced by the Ca II IRT index is enhanced after the intermediate-period gap. The local minimum at the gap and the local maximum after it appear at periods and Rossby numbers that closely match the corresponding features already identified in the photospheric Sph index, indicating that the gap marks a real transition in stellar magnetic behavior across atmospheric layers.

What carries the argument

The signed distance from the gap, delta log P_rot = log P_rot,star - log P_rot,gap(color), together with the 95th-percentile upper envelope of log R'_IRT in bins of period or Rossby number. These locate the activity dip and post-gap enhancement and allow direct comparison with the Sph features.

Load-bearing premise

That the upper envelope of a much smaller, non-contemporaneous chromospheric sample still faithfully traces the same physical activity maximum that defines the gap in the photospheric index.

What would settle it

A larger sample of contemporaneous Ca II IRT (or equivalent chromospheric) measurements that fills the same period-color plane would either recover or erase the post-gap activity peak at the same Rossby numbers reported for Sph.

Watch this falsifier — get emailed when new claim-graph text bears on it.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit.

Referee Report

0 major / 4 minor

Summary. The manuscript computes the Gaia DR3 Ca II infrared-triplet activity index (log R'_IRT) for Kepler field stars that already have homogeneous rotation periods and photospheric activity proxies ⟨Sph⟩ from Santos et al. (2019, 2021). After quality cuts the intersection sample of main-sequence stars is N = 1 944. The authors show that log R'_IRT correlates with ⟨Sph⟩ (Spearman ρ ≈ 0.47 overall, stronger for G/K dwarfs), that later spectral types are systematically more active at fixed Prot, and that the upper envelope (95th percentile) of log R'_IRT exhibits a local minimum near the intermediate-period gap followed by a local maximum after the gap. These inflections occur at Prot and Rossby-number values that closely match the previously published ⟨Sph⟩ features (Table 3, Figs. 6–7). Multiplicity is shown to raise the activity upper envelope for the fastest rotators. The central claim is carefully phrased as “hints” of a chromospheric counterpart to the photospheric activity transition across the gap.

Significance. If the alignment of the IRT and Sph features is physical, the intermediate-period gap is a genuine transition in magnetic behaviour that spans both photosphere and chromosphere. That strengthens the core-envelope coupling interpretation of the gap and stalling, supplies an independent chromospheric diagnostic for magneto-gyro-chronology, and has direct implications for the high-energy environments of exoplanets around K and G dwarfs. The work is a clean, homogeneous cross-match of two large public catalogues, reports the full target list and gap parametrization, and correctly hedges the claim given the factor-of-∼20 sample-size reduction and non-contemporaneous epochs. These are genuine strengths of the analysis.

minor comments (4)
  1. In Sect. 5.1 and the caption of Fig. 6 the text states that the IRT enhancement for G dwarfs occurs at a longer Prot than the Sph local maximum (Table 3). A short quantitative statement of the offset (e.g., ΔProt ≈ 2 d) would help the reader judge how close the alignment really is.
  2. Appendix A demonstrates that the percentile trends are insensitive to binning choices, but the precise window widths and Gaussian-kernel widths actually used for the published 50th- and 95th-percentile curves are not listed. Adding those numbers (or a short table) would improve reproducibility.
  3. The early-F / late-F division is taken at the Kraft-break colour of Beyer & White (2024). A one-sentence justification that this colour also coincides with the blue edge of the gap definition would remove any residual ambiguity.
  4. A few typographical inconsistencies remain (e.g., “Caii” vs. “Ca II”, occasional missing spaces before units). A final copy-edit pass would be beneficial.

Circularity Check

1 steps flagged

No significant circularity: independent Gaia Ca II IRT measurements are compared to a prior Sph-defined gap location; the IRT dip/enhancement is not forced by construction.

specific steps
  1. self citation load bearing [Sect. 2.3, Table 2, Eq. 1; Sect. 5.1, Table 3, Figs. 6–7]
    "we followed the above definition of the intermediate-period gap, namely the Prot value at which there is a local minimum in ⟨Sph⟩. … we determined the location of the gap as a function of de-reddened Gaia DR3 color … The resulting parametrization is reported in Table 2 … δlog Prot = log Prot,star − log Prot,gap … the vertical lines indicate the location (in terms of Prot) of the local minimum … and local maximum … of photospheric activity as probed by the ⟨Sph⟩ 95th-percentile"

    The gap location (and the vertical markers of Sph local min/max) is taken from prior work by overlapping authors (Santos et al. 2025 procedure; Mathur et al. 2025 Ro). This is ordinary self-citation for a comparison sample, not a uniqueness theorem or definition that forces the IRT envelope to show a dip/enhancement; the IRT values themselves remain independent. Minor and non-load-bearing for the stated claim.

full rationale

The paper's central claim is an observational comparison: the intermediate-period gap is located from the local minimum in the photospheric ⟨Sph⟩ index (following the procedure of Santos et al. 2025, adapted to Gaia colors; Table 2 and Eq. 1), after which the independently computed log R'_IRT (from Gaia DR3 α via Lanzafame et al. 2023 Eqs. 2–3, with a 3σ cut) is examined versus Prot and Ro. The 95th-percentile upper envelope of log R'_IRT is then inspected for inflections near those same Prot/Ro values (Figs. 6–7, Table 3). Because log R'_IRT is measured from a separate spectroscopic data set (non-contemporaneous with Kepler, magnitude-limited, sample ~20 imes smaller), the presence of a dip at the gap and a subsequent enhancement is an empirical finding, not an algebraic identity or a fitted parameter renamed as a prediction. Self-citations to overlapping-author Sph papers (Santos et al., Mathur et al.) supply the gap definition and Ro values used for comparison, but do not enter the IRT calculation itself and are not load-bearing uniqueness theorems or ansatzes that force the IRT result. Spectral-type trends, multiplicity effects, and the Sph–IRT correlation are likewise direct data products. No equation equates the IRT envelope to the Sph input by construction; the language is carefully hedged as 'hints' of alignment. Score 1 reflects only the minor, non-load-bearing self-citation of the gap location; the derivation chain is otherwise self-contained against external benchmarks.

Axiom & Free-Parameter Ledger

2 free parameters · 4 axioms · 0 invented entities

The claim rests on standard stellar-dynamo and gyrochronology assumptions plus catalog-derived quantities; no new free parameters are fitted to force the IRT enhancement, and no novel physical entities are postulated.

free parameters (2)
  • gap location P_rot,gap((BP-RP)_0) = color-dependent median periods ~0.66- several days
    Parametrized from Sph local minima via bootstrapped binning (Table 2); used to define δlog P_rot and to place vertical lines in IRT diagrams.
  • percentile binning window and smoothing kernel
    Fixed logarithmic width plus 1-D Gaussian convolution chosen to produce the 50th/95th-percentile curves shown in Figs. 4-7; Appendix A shows robustness but the exact width is a free choice.
axioms (4)
  • domain assumption Surface rotation periods and Sph measured from Kepler light curves are reliable tracers of photospheric magnetic activity for the unsaturated regime.
    Adopted from Santos et al. (2019, 2021) and used throughout Sects. 2 and 5.
  • domain assumption Gaia DR3 α activity indices converted via the Lanzafame et al. (2023) metallicity-dependent polynomials yield a valid chromospheric log R'_IRT after a 3σ cut.
    Eqs. 2-3 and quality cut in Sect. 3; small sensitivity tests reported but the conversion is taken as given.
  • domain assumption The 95th-percentile upper envelope of activity versus period (or Ro) is dominated by equator-on stars near cycle maximum and therefore traces the true activity-rotation relation.
    Explicitly invoked in Sect. 5.1 to justify focusing on the upper envelope rather than the median.
  • domain assumption Core-envelope angular-momentum coupling is the physical cause of the intermediate-period gap and the associated activity features.
    Adopted from Spada & Lanzafame and related works; used interpretively in Sects. 1 and 5.2 but not required for the observational claim.

pith-pipeline@v1.1.0-grok45 · 33166 in / 2577 out tokens · 25136 ms · 2026-07-11T04:18:39.819679+00:00 · methodology

0 comments
read the original abstract

For low-mass stars (M < 1.4 Msun), the connection between stellar rotation and magnetic activity governs stellar spin-down, shapes the environments of their exoplanets, and provides an age-diagnostic via magneto-gyro-chronology. Recently, unexpected phenomena known as the intermediate rotation period gap and the rotational stalling have been discovered. These are likely due to internal angular momentum redistribution, and mark departures from a smooth spin-down evolution. These features have been shown to cause enhanced magnetic activity on the photosphere, as measured by the photometric index from light curves (Sph), in both cluster and field stars. However, their influence on other magnetic activity proxies, and particularly in field stars, remains poorly understood. In this work, we study the impact of the intermediate-period gap on chromospheric magnetic activity as traced by the Ca ii infrared triplet (IRT) index. We target the stars observed by the Kepler mission, as this is the largest and most reliable sample of field stars with measured rotation periods sensitive to the gap. We calculate the Ca ii IRT index for the Kepler stars using the spectroscopic information from the Gaia mission data release three (DR3). We study the rotation-activity relation as a function of spectral type, finding that K dwarfs are more active than G dwarfs, which in turn are more active than F dwarfs. For main-sequence stars, we find that chromospheric magnetic activity is also enhanced after the intermediate-period gap, mirroring its effect on the photospheric Sph index. Our work reveals that the intermediate-period gap marks a genuine transition in stellar magnetic behavior, not only at the photosphere but also at the chromosphere. This highlights the need to account for its signatures across activity proxies, as well as its impact on exoplanet habitability and the age-rotation-activity relation.

Figures

Figures reproduced from arXiv: 2607.05651 by Angela R. G. Santos, Desmond H. Grossmann, Diego Godoy-Rivera, Paul G. Beck, Rafael A. Garcia, Savita Mathur, Tyler Richey-Yowell, Zachary R. Claytor.

Figure 1
Figure 1. Figure 1: Characterization of the rotating Kepler stars. Top: distribution of rotation periods. Middle: CMD with the full Kepler sample shown in grey, and the subset with measured rotation periods shown colored by their Prot values. The dashed line shows the separation between Joint￾MS and Joint-Evolved targets, and the vertical dotted line illustrates the Kraft break. Bottom: Prot vs. color diagram for the Joint-MS… view at source ↗
Figure 3
Figure 3. Figure 3: Venn diagram for the subsets of stars classified as Joint MS (pur￾ple), with a measured rotation period and photometric activity index (green), and with a measured Ca ii IRT index (red). pre-MS stars or accreting T Tauri stars, which would otherwise occupy the highest activity regime (Lanzafame et al. 2023). For further reliability, we tested the significance of the above coefficient-interpolation assumpti… view at source ↗
Figure 2
Figure 2. Figure 2: Analogous to [PITH_FULL_IMAGE:figures/full_fig_p005_2.png] view at source ↗
Figure 4
Figure 4. Figure 4: shows the comparison of the photospheric index ⟨Sph⟩ (Sect. 2.2) vs. the chromospheric index log R ′ IRT (Sect. 3) for the Joint-MS sample. For reference, the solid black line shows the 50th-percentile of the log R ′ IRT distribution in bins of ⟨Sph⟩. Further details on the binning procedure are described in Ap￾pendix A. There is a clear correlation between both proxies, es￾pecially in the regime of higher… view at source ↗
Figure 5
Figure 5. Figure 5: Ca ii IRT activity index vs. rotation period, as a function of spec￾tral type (K dwarfs in orange, G dwarfs in green, late-F dwarfs in blue, and early-F dwarfs in magenta). Typical uncertainties are illustrated by the median σ symbol. The lines show their respective 50th-percentiles, with their slopes getting steeper towards lower stellar masses. At a given rotation period, later spectral types typically h… view at source ↗
Figure 6
Figure 6. Figure 6: Ca ii IRT activity index vs. rotation period, separated by spectral type. From top to bottom these are: K dwarfs, G dwarfs, and late-F dwarfs. Stars are color-coded by their δ log Prot values (if available). In each panel, the dashed line represents the 95th-percentile. Typical uncertainties are illustrated by the median σ symbols. The vertical lines (see [PITH_FULL_IMAGE:figures/full_fig_p008_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: shows log R ′ IRT vs. the normalized Rossby number for the Joint-MS sample, with the different spectral types indi￾cated by the colors. The 95th-percentile of the log R ′ IRT distri￾bution in bins of (Ro/Ro⊙) is shown as the black dashed line. Considering the sample as a whole, we observe an overall de￾crease in the chromospheric activity index with increasing Ro. Such a behavior is consistent with what ha… view at source ↗
Figure 8
Figure 8. Figure 8: Impact of multiplicity on the magnetic activity of MS targets as probed by the chromospheric Ca ii IRT (left column) and the photospheric ⟨Sph⟩ (right column). Top: activity index vs. rotation period, as a function of stellar multiplicity (singles in brown and binaries in violet). The dashed lines show the 95th-percentile of each distribution. In the regime of rapid rotators (Prot ≲ 5 – 10 days), binary sy… view at source ↗

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

219 extracted references · 125 canonical work pages · 98 internal anchors

  1. [1]

    A New Look at an Old Cluster: The Membership, Rotation, and Magnetic Activity of Low-Mass Stars in the 1.3-Gyr-Old Open Cluster NGC 752

    A New Look at an Old Cluster: The Membership, Rotation, and Magnetic Activity of Low-mass Stars in the 1.3 Gyr Old Open Cluster NGC 752. , keywords =. doi:10.3847/1538-4357/aac6ed , archivePrefix =. 1804.02016 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-4357/aac6ed

  2. [2]

    Magnetic and tidal migration of close-in planets. Influence of secular evolution on their population

    Magnetic and tidal migration of close-in planets. Influence of secular evolution on their population. , keywords =. doi:10.1051/0004-6361/202040173 , archivePrefix =. 2104.01004 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/202040173

  3. [3]

    , keywords =

    The 16th Data Release of the Sloan Digital Sky Surveys: First Release from the APOGEE-2 Southern Survey and Full Release of eBOSS Spectra. , keywords =. doi:10.3847/1538-4365/ab929e , archivePrefix =. 1912.02905 , primaryClass =

    doi:10.3847/1538-4365/ab929e 1912

  4. [4]

    Impact of Space Weather on Climate and Habitability of Terrestrial Type Exoplanets

    Impact of space weather on climate and habitability of terrestrial-type exoplanets. International Journal of Astrobiology , keywords =. doi:10.1017/S1473550419000132 , archivePrefix =. 1905.05093 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1017/s1473550419000132 1905

  5. [5]

    , keywords =

    The effects of stellar activity cycles on planetary atmospheric escape and the He I 1083 nm transit signature. , keywords =. doi:10.1093/mnras/staf1855 , archivePrefix =. 2510.23282 , primaryClass =

    work page doi:10.1093/mnras/staf1855

  6. [6]

    The Ca II Infrared Triplet as a stellar activity diagnostic . I. Non-LTE photospheric profiles and definition of the R _ IRT indicator. , keywords =. doi:10.1051/0004-6361:20041745 , adsurl =

    doi:10.1051/0004-6361:20041745

  7. [7]

    Calibrating Gyrochronology using Kepler Asteroseismic targets

    Calibrating gyrochronology using Kepler asteroseismic targets. , keywords =. doi:10.1093/mnras/stv423 , archivePrefix =. 1502.06965 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/stv423

  8. [8]

    Towards precise stellar ages: combining isochrone fitting with empirical gyrochronology

    Toward Precise Stellar Ages: Combining Isochrone Fitting with Empirical Gyrochronology. , keywords =. doi:10.3847/1538-3881/ab3c53 , archivePrefix =. 1908.07528 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-3881/ab3c53 1908

  9. [9]

    Exploring the evolution of stellar rotation using Galactic kinematics

    Exploring the Evolution of Stellar Rotation Using Galactic Kinematics. , keywords =. doi:10.3847/1538-3881/ab91b2 , archivePrefix =. 2005.09387 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-3881/ab91b2 2005

  10. [10]

    Solar Models: current epoch and time dependences, neutrinos, and helioseismological properties

    Solar Models: Current Epoch and Time Dependences, Neutrinos, and Helioseismological Properties. , keywords =. doi:10.1086/321493 , archivePrefix =. astro-ph/0010346 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1086/321493

  11. [11]

    Chromospheric Variations in Main-Sequence Stars. II. , keywords =. doi:10.1086/175072 , adsurl =

    doi:10.1086/175072

  12. [12]

    , keywords =

    On the Rotational Evolution of Solar- and Late-Type Stars, Its Magnetic Origins, and the Possibility of Stellar Gyrochronology. , keywords =. doi:10.1086/367639 , archivePrefix =. astro-ph/0303631 , primaryClass =

    Pith/arXiv arXiv doi:10.1086/367639

  13. [13]

    , keywords =

    Ages for Illustrative Field Stars Using Gyrochronology: Viability, Limitations, and Errors. , keywords =. doi:10.1086/519295 , archivePrefix =. 0704.3068 , primaryClass =

    Pith/arXiv arXiv doi:10.1086/519295

  14. [14]

    , keywords =

    Testing tidal theory for evolved stars by using red giant binaries observed by Kepler. , keywords =. doi:10.1093/mnrasl/sly114 , archivePrefix =. 1806.07208 , primaryClass =

    Pith/arXiv arXiv doi:10.1093/mnrasl/sly114

  15. [15]

    Constraining stellar and orbital co-evolution through ensemble seismology of solar-like oscillators in binary systems -- A census of oscillating red-giants and main-sequence stars in Gaia DR3 binaries

    Constraining stellar and orbital co-evolution through ensemble seismology of solar-like oscillators in binary systems. A census of oscillating red giants and dwarf stars in Gaia DR3 binaries. , keywords =. doi:10.1051/0004-6361/202346810 , archivePrefix =. 2307.10812 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/202346810

  16. [16]

    , keywords =

    Tales of stellar and binary coevolution, told by stellar oscillations: Binary demographics and their impact on stellar mass, orbits, and age estimates in main-sequence and red-giant stars. , keywords =. doi:10.1051/0004-6361/202555157 , archivePrefix =. 2512.13581 , primaryClass =

    work page doi:10.1051/0004-6361/202555157

  17. [17]

    , keywords =

    Dynamical mass of a solar-like oscillator at the main sequence turnoff from Gaia astrometry and ground-based spectroscopy. , keywords =. doi:10.1051/0004-6361/202557452 , archivePrefix =. 2601.14197 , primaryClass =

    work page doi:10.1051/0004-6361/202557452

  18. [18]

    , keywords =

    The Zwicky Transient Facility: System Overview, Performance, and First Results. , keywords =. doi:10.1088/1538-3873/aaecbe , archivePrefix =. 1902.01932 , primaryClass =

    Pith/arXiv arXiv doi:10.1088/1538-3873/aaecbe 1902

  19. [19]

    Spectroscopic and seismic analysis of red giants in eclipsing binaries discovered by Kepler

    Spectroscopic and seismic analysis of red giants in eclipsing binaries discovered by Kepler. , keywords =. doi:10.1051/0004-6361/202037783 , archivePrefix =. 2101.05351 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/202037783

  20. [20]

    The Gaia-Kepler Stellar Properties Catalog. I. Homogeneous Fundamental Properties for 186,301 Kepler Stars. , keywords =. doi:10.3847/1538-3881/159/6/280 , archivePrefix =. 2001.07737 , primaryClass =

    Pith/arXiv arXiv doi:10.3847/1538-3881/159/6/280 2001

  21. [21]

    , keywords =

    The Kraft Break Sharply Divides Low-mass and Intermediate-mass Stars. , keywords =. doi:10.3847/1538-4357/ad6b0d , archivePrefix =. 2408.02638 , primaryClass =

    Pith/arXiv arXiv doi:10.3847/1538-4357/ad6b0d

  22. [22]

    Three-dimensional modeling of the Ca II H&K lines in the solar atmosphere

    Three-dimensional modeling of the Ca II H and K lines in the solar atmosphere. , keywords =. doi:10.1051/0004-6361/201731926 , archivePrefix =. 1712.01045 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/201731926

  23. [23]

    , keywords =

    Chromospheric Activity in G and K Main-Sequence Stars, and What It Tells Us about Stellar Dynamos. , keywords =. doi:10.1086/510482 , adsurl =

    doi:10.1086/510482

  24. [24]

    , keywords =

    Asteroseismic Calibration of the Rossby Number and Its Connection to the Stellar Dynamo and Fundamental Properties. , keywords =. doi:10.3847/1538-4357/ae12f2 , archivePrefix =. 2510.12471 , primaryClass =

    doi:10.3847/1538-4357/ae12f2

  25. [25]

    Questioning the active branch of stellar activity cycles

    Chromospheric activity catalogue of 4454 cool stars. Questioning the active branch of stellar activity cycles. , keywords =. doi:10.1051/0004-6361/201629518 , archivePrefix =. 1803.11123 , primaryClass =

    Pith/arXiv arXiv doi:10.1051/0004-6361/201629518

  26. [26]

    Science , keywords =

    Kepler Planet-Detection Mission: Introduction and First Results. Science , keywords =. doi:10.1126/science.1185402 , adsurl =

    doi:10.1126/science.1185402

  27. [27]

    The Empirical Limits of Gyrochronology

    The Empirical Limits of Gyrochronology. , keywords =. doi:10.3847/2041-8213/acc589 , archivePrefix =. 2303.08830 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/2041-8213/acc589 2041

  28. [28]

    Enhanced stellar activity for slow antisolar differential rotation?

    Enhanced Stellar Activity for Slow Antisolar Differential Rotation?. , keywords =. doi:10.3847/2041-8213/aab20a , archivePrefix =. 1802.08689 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/2041-8213/aab20a 2041

  29. [29]

    , keywords =

    Rotation of young solar-type stars as seen by Gaia and K2. , keywords =. doi:10.1051/0004-6361/202553912 , archivePrefix =. 2507.20909 , primaryClass =

    work page doi:10.1051/0004-6361/202553912

  30. [30]

    , keywords =

    Kepler Input Catalog: Photometric Calibration and Stellar Classification. , keywords =. doi:10.1088/0004-6256/142/4/112 , archivePrefix =. 1102.0342 , primaryClass =

    Pith/arXiv arXiv doi:10.1088/0004-6256/142/4/112

  31. [31]

    , keywords =

    Linking chromospheric activity and magnetic field properties for late-type dwarf stars. , keywords =. doi:10.1093/mnras/stac1291 , archivePrefix =. 2205.03108 , primaryClass =

    Pith/arXiv arXiv doi:10.1093/mnras/stac1291

  32. [32]

    EAS2024, European Astronomical Society Annual Meeting , year = 2024, month = jul, eid =

    Status of Gaia Data Release 4 processing. EAS2024, European Astronomical Society Annual Meeting , year = 2024, month = jul, eid =

    2024

  33. [33]

    Living Reviews in Solar Physics , keywords =

    Magnetism, dynamo action and the solar-stellar connection. Living Reviews in Solar Physics , keywords =. doi:10.1007/s41116-017-0007-8 , adsurl =

    doi:10.1007/s41116-017-0007-8

  34. [34]

    , keywords =

    Powering Stellar Magnetism: Energy Transfers in Cyclic Dynamos of Sun-like Stars. , keywords =. doi:10.3847/1538-4357/ac469b , archivePrefix =. 2201.13218 , primaryClass =

    doi:10.3847/1538-4357/ac469b

  35. [35]

    The Ca II infrared triplet as a stellar activity diagnostic. II. Test and calibration with high resolution observations. , keywords =. doi:10.1051/0004-6361:20065588 , adsurl =

    doi:10.1051/0004-6361:20065588

  36. [36]

    Starspots and Magnetism: Testing the Activity Paradigm in the Pleiades and M67

    Star-spots and magnetism: testing the activity paradigm in the Pleiades and M67. , keywords =. doi:10.1093/mnras/stac2706 , archivePrefix =. 2209.10549 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/stac2706

  37. [37]

    Core-envelope decoupling drives radial shear dynamos in cool stars

    Core-envelope Decoupling Drives Radial Shear Dynamos in Cool Stars. , keywords =. doi:10.3847/2041-8213/acd780 , archivePrefix =. 2301.07716 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/2041-8213/acd780 2041

  38. [38]

    A New Age-Activity Relation For Solar Analogs that Accounts for Metallicity

    A New Age Activity Relation For Solar Analogs that Accounts for Metallicity. , keywords =. doi:10.3847/2041-8213/adc382 , archivePrefix =. 2504.17482 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/2041-8213/adc382 2041

  39. [39]

    , keywords =

    Surface rotation of Kepler red giant stars. , keywords =. doi:10.1051/0004-6361/201629884 , archivePrefix =. 1707.05989 , primaryClass =

    Pith/arXiv arXiv doi:10.1051/0004-6361/201629884

  40. [40]

    Unravelling the Period Gap using LAMOST Chromospheric Activity Indices

    Unravelling the period gap using LAMOST chromospheric activity indices. , keywords =. doi:10.1093/mnras/stad2521 , archivePrefix =. 2308.10539 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/stad2521

  41. [41]

    , year = 2014, month = aug, volume =

    Solar Dynamo Theory. , year = 2014, month = aug, volume =. doi:10.1146/annurev-astro-081913-040012 , adsurl =

    doi:10.1146/annurev-astro-081913-040012 2014

  42. [42]

    Living Reviews in Solar Physics , keywords =

    Dynamo models of the solar cycle. Living Reviews in Solar Physics , keywords =. doi:10.1007/s41116-020-00025-6 , adsurl =

    doi:10.1007/s41116-020-00025-6

  43. [43]

    Chemical Evolution in the Milky Way: Rotation-based ages for APOGEE-Kepler cool dwarf stars

    Chemical Evolution in the Milky Way: Rotation-based Ages for APOGEE-Kepler Cool Dwarf Stars. , keywords =. doi:10.3847/1538-4357/ab5c24 , archivePrefix =. 1911.04518 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-4357/ab5c24 1911

  44. [44]

    New Rotation Periods from the Kepler Bonus Background Light Curves

    New Rotation Periods from the Kepler Bonus Background Light Curves. , keywords =. doi:10.3847/1538-4357/add5f0 , archivePrefix =. 2506.03248 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-4357/add5f0

  45. [45]

    A calibration of the Rossby number from asteroseismology

    A calibration of the Rossby number from asteroseismology. , keywords =. doi:10.1051/0004-6361/202141395 , archivePrefix =. 2107.08551 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/202141395

  46. [46]

    A Temporary Epoch of Stalled Spin-Down for Low-Mass Stars: Insights from NGC 6811 with Gaia and Kepler

    A Temporary Epoch of Stalled Spin-down for Low-mass Stars: Insights from NGC 6811 with Gaia and Kepler. , keywords =. doi:10.3847/1538-4357/ab2393 , archivePrefix =. 1905.06869 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-4357/ab2393 1905

  47. [47]

    When Do Stalled Stars Resume Spinning Down? Advancing Gyrochronology with Ruprecht 147

    When Do Stalled Stars Resume Spinning Down? Advancing Gyrochronology with Ruprecht 147. , keywords =. doi:10.3847/1538-4357/abbf58 , archivePrefix =. 2010.02272 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-4357/abbf58 2010

  48. [48]

    Rotating Stars from Kepler Observed with Gaia DR1

    Rotating Stars from Kepler Observed with Gaia DR1. , keywords =. doi:10.3847/1538-4357/835/1/16 , archivePrefix =. 1610.08563 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-4357/835/1/16

  49. [49]

    Rotating Stars from Kepler Observed with Gaia DR2

    Rotating Stars from Kepler Observed with Gaia DR2. , keywords =. doi:10.3847/1538-4357/aae842 , archivePrefix =. 1807.09841 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-4357/aae842

  50. [50]

    , keywords =

    Further Evidence of Modified Spin-down in Sun-like Stars: Pileups in the Temperature-Period Distribution. , keywords =. doi:10.3847/1538-4357/ac6dd3 , archivePrefix =. 2203.08920 , primaryClass =

    Pith/arXiv arXiv doi:10.3847/1538-4357/ac6dd3

  51. [51]

    Activity of low mass stars in the light of spot signature in the Fourier domain

    Activity of low-mass stars in the light of spot signature in the Fourier domain. , keywords =. doi:10.1051/0004-6361/202451205 , archivePrefix =. 2502.15329 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/202451205

  52. [52]

    YREC: The Yale Rotating Stellar Evolution Code

    YREC: the Yale rotating stellar evolution code. Non-rotating version, seismology applications. , keywords =. doi:10.1007/s10509-007-9698-y , archivePrefix =. 0710.4003 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1007/s10509-007-9698-y

  53. [53]

    , keywords =

    Observations of the CA II Infrared Triplet in Chromospherically Active Single and Binary Stars. , keywords =. doi:10.1086/191779 , adsurl =

    work page doi:10.1086/191779

  54. [54]

    Angular Momentum Transport In Solar-Type Stars: Testing the Timescale For Core-Envelope Coupling

    Angular Momentum Transport in Solar-type Stars: Testing the Timescale for Core-Envelope Coupling. , keywords =. doi:10.1088/0004-637X/716/2/1269 , archivePrefix =. 0911.1121 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1088/0004-637x/716/2/1269

  55. [55]

    Double-edged sword: the influence of tidal interaction on stellar activity in binaries

    Double-edged Sword: The Influence of Tidal Interaction on Stellar Activity in Binaries. , keywords =. doi:10.3847/1538-4357/ad8eb9 , archivePrefix =. 2410.15039 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-4357/ad8eb9

  56. [56]

    Rotationally Driven Ultraviolet Emission of Red Giant Stars

    Rotationally Driven Ultraviolet Emission of Red Giant Stars. , keywords =. doi:10.3847/1538-3881/ab9080 , archivePrefix =. 2005.00577 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-3881/ab9080 2005

  57. [57]

    Rotationally Driven Ultraviolet Emission of Red Giant Stars. II. Metallicity, Activity, Binarity, and Subsubgiants. , keywords =. doi:10.3847/1538-3881/adc92a , archivePrefix =. 2504.05561 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-3881/adc92a

  58. [58]

    , keywords =

    Stellar Multiplicity. , keywords =. doi:10.1146/annurev-astro-081710-102602 , archivePrefix =. 1303.3028 , primaryClass =

    Pith/arXiv arXiv doi:10.1146/annurev-astro-081710-102602

  59. [59]

    A 4 Gyr M-dwarf Gyrochrone from CFHT/MegaPrime Monitoring of the Open Cluster M67

    A 4 Gyr M-dwarf Gyrochrone from CFHT/MegaPrime Monitoring of the Open Cluster M67. , keywords =. doi:10.3847/1538-4357/ac90be , archivePrefix =. 2211.01377 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-4357/ac90be

  60. [60]

    , keywords =

    Multiplicity among Solar Type Stars in the Solar Neighbourhood - Part Two - Distribution of the Orbital Elements in an Unbiased Sample. , keywords =

  61. [61]

    How Good a Clock is Rotation? The Stellar Rotation-Mass-Age Relationship for Old Field Stars

    How Good a Clock is Rotation? The Stellar Rotation-Mass-Age Relationship for Old Field Stars. , keywords =. doi:10.1088/0004-637X/780/2/159 , archivePrefix =. 1203.1618 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1088/0004-637x/780/2/159

  62. [62]

    , keywords =

    Red giant asteroseismic binaries in the Kepler field: Identifying gravitationally bound systems. , keywords =. doi:10.1051/0004-6361/202555884 , archivePrefix =. 2509.13412 , primaryClass =

    work page doi:10.1051/0004-6361/202555884

  63. [63]

    The stellar corona-chromosphere connection. A comprehensive study of X-ray and Ca II IRT fluxes from eROSITA and Gaia

    The stellar corona-chromosphere connection: A comprehensive study of X-ray and Ca II IRT fluxes from eROSITA and Gaia. , keywords =. doi:10.1051/0004-6361/202451421 , archivePrefix =. 2504.17593 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/202451421

  64. [64]

    A detailed understanding of the rotation-activity relationship using the 300 Myr old open cluster NGC 3532

    A detailed understanding of the rotation-activity relationship using the 300 Myr old open cluster NGC 3532. , keywords =. doi:10.1051/0004-6361/202140896 , archivePrefix =. 2112.03302 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/202140896

  65. [65]

    The Kepler Follow-up Observation Program. II. Stellar Parameters from Medium- and High-resolution Spectroscopy. , keywords =. doi:10.3847/1538-4357/aaca34 , archivePrefix =. 1805.12089 , primaryClass =

    Pith/arXiv arXiv doi:10.3847/1538-4357/aaca34

  66. [66]

    , keywords =

    The Gaia mission. , keywords =. doi:10.1051/0004-6361/201629272 , archivePrefix =. 1609.04153 , primaryClass =

    Pith/arXiv arXiv doi:10.1051/0004-6361/201629272

  67. [67]

    Summary of the contents and survey properties

    Gaia Early Data Release 3. Summary of the contents and survey properties. , keywords =. doi:10.1051/0004-6361/202039657 , archivePrefix =. 2012.01533 , primaryClass =

    Pith/arXiv arXiv doi:10.1051/0004-6361/202039657 2012

  68. [68]

    Summary of the content and survey properties

    Gaia Data Release 3. Summary of the content and survey properties. , keywords =. doi:10.1051/0004-6361/202243940 , archivePrefix =. 2208.00211 , primaryClass =

    Pith/arXiv arXiv doi:10.1051/0004-6361/202243940

  69. [69]

    Gaia Data Release 3: Stellar multiplicity, a teaser for the hidden treasure

    Gaia Data Release 3. Stellar multiplicity, a teaser for the hidden treasure. , keywords =. doi:10.1051/0004-6361/202243782 , archivePrefix =. 2206.05595 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/202243782

  70. [70]

    , keywords =

    Improved angular momentum evolution model for solar-like stars. , keywords =. doi:10.1051/0004-6361/201321302 , archivePrefix =. 1306.2130 , primaryClass =

    Pith/arXiv arXiv doi:10.1051/0004-6361/201321302

  71. [71]

    Improved angular momentum evolution model for solar-like stars. II. Exploring the mass dependence. , keywords =. doi:10.1051/0004-6361/201525660 , archivePrefix =. 1502.05801 , primaryClass =

    Pith/arXiv arXiv doi:10.1051/0004-6361/201525660

  72. [72]

    , keywords =

    Preparation of Kepler light curves for asteroseismic analyses. , keywords =. doi:10.1111/j.1745-3933.2011.01042.x , archivePrefix =. 1103.0382 , primaryClass =

    doi:10.1111/j.1745-3933.2011.01042.x 2011

  73. [73]

    Towards asteroseismically calibrated age-rotation relations

    Rotation and magnetism of Kepler pulsating solar-like stars. Towards asteroseismically calibrated age-rotation relations. , keywords =. doi:10.1051/0004-6361/201423888 , archivePrefix =. 1403.7155 , primaryClass =

    Pith/arXiv arXiv doi:10.1051/0004-6361/201423888

  74. [74]

    Impact on asteroseismic analyses of regular gaps in Kepler data

    Impact on asteroseismic analyses of regular gaps in Kepler data. , keywords =. doi:10.1051/0004-6361/201323326 , archivePrefix =. 1405.5374 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/201323326

  75. [75]

    , keywords =

    The Revolution Revolution: Magnetic Morphology Driven Spin-down. , keywords =. doi:10.3847/1538-4357/aace5d , archivePrefix =. 1804.01986 , primaryClass =

    Pith/arXiv arXiv doi:10.3847/1538-4357/aace5d

  76. [76]

    Surface Activity and Oscillation Amplitudes of Red Giants in Eclipsing Binaries

    Surface Activity and Oscillation Amplitudes of Red Giants in Eclipsing Binaries. , keywords =. doi:10.1088/0004-637X/785/1/5 , archivePrefix =. 1402.3027 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1088/0004-637x/785/1/5

  77. [77]

    Active red giants: close binaries versus single rapid rotators

    Active red giants: Close binaries versus single rapid rotators. , keywords =. doi:10.1051/0004-6361/202037781 , archivePrefix =. 2004.13792 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/202037781 2004

  78. [78]

    Chinese Journal of Space Science , keywords =

    Search for a Second Earth - the Earth 2.0 (ET) Space Mission. Chinese Journal of Space Science , keywords =. doi:10.11728/cjss2024.03.yg05 , adsurl =

    doi:10.11728/cjss2024.03.yg05

  79. [79]

    Surface magnetism of rapidly rotating red giants: single versus close binary stars

    Surface magnetism of rapidly rotating red giants: Single versus close binary stars. , keywords =. doi:10.1051/0004-6361/202245083 , archivePrefix =. 2211.01026 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/202245083

  80. [80]

    Magnetic activity of red giants: correlation between the amplitude of solar-like oscillations and chromospheric indicators

    Magnetic activity of red giants: Correlation between the amplitude of solar-like oscillations and chromospheric indicators. , keywords =. doi:10.1051/0004-6361/202349008 , archivePrefix =. 2401.13549 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/202349008

Showing first 80 references.