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REVIEW 4 major objections 6 minor 102 references

Carbon Stars From Gaia DR3 and the Space Density of Dwarf Carbon Stars

T0 review · 4 major / 6 minor · reviewed 2026-08-09 · deepseek-v4-flash

Pith's one-line read Dwarf carbon stars are rare relics of AGB mass transfer, and this paper gives their first reliable space density: about one per 50-pc local disk volume, with a scale height near 856 pc.

desk verdict A genuinely new all-sky dC catalog and first space density, but the completeness correction is self-referential and, if anything, the reported density is a lower limit with underestimated errors. read the letter →

arxiv 2501.18763 v1 pith:USWPWVQ4 submitted 2025-01-30 astro-ph.SR

classification astro-ph.SR
keywords carbonstarsdwarfGaiaDR3XPspectramachinelearningclassificationspacedensityluminosityfunctiondiskscaleheight
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 builds an all-sky catalog of carbon-star candidates from Gaia DR3 low-resolution spectra and uses it to answer a question that had no reliable published answer: how common are dwarf carbon stars (dCs), main-sequence stars that inherited carbon from a now-dead AGB companion? The headline result is a local mid-plane space density of $\rho_0 = 1.96^{+0.14}_{-0.12} \times 10^{-6}\,\mathrm{pc}^{-3}$ for dCs with $5.5 < M_G < 9.5$, about one dC per 50-pc-radius local disk volume, and a disk scale height of $856^{+49}_{-43}$ pc. Because dCs are far more numerous than carbon giants and each one records a past episode of mass transfer, the density pins down how many carbon-rich AGB stars end up in observable post-mass-transfer systems. The paper also reports sample purity from follow-up spectroscopy and completeness estimates, with the caveat that completeness is measured by how well the classifier recovers its own training sample.

What carries the argument

The load-bearing machinery is a set of 20 spectral indices computed from Gaia XP spectra, defined as ratios of mean flux inside a molecular band (C$_2$ or CN) to mean flux in a nearby pseudo-continuum window, with wavelength windows chosen so that bands overlapping normal-star features (Ca II, Mg I, CH, C$_2$ 5165) are excluded. These indices are combined with 110 normalized BP/RP Hermite coefficients and three Gaia colors, and fed to XGBoost and Random Forest classifiers trained on 926 visually vetted LAMOST C stars and a random control sample; the candidate sample is the intersection of both classifiers, and the density sample applies XGProb_C $> 0.85$. For the density, each star's maximum visible distance from the $G=16.5$ limit sets the volume of a Galactic-plane-parallel spherical slab, the luminosity function in each $z$ bin is filled by interpolating missing $M_G$ bins from the closest $z$ bin, and exponential and sech$^2(z/H_z)$ models are fit with Markov chain Monte Carlo.

What would settle it

Count how many dwarf carbon stars independently classified in SDSS or in LAMOST releases after the training data were drawn, with Gaia XP spectra available, $G<16.5$, $|b|>10^\circ$, and $M_G>5.5$, are recovered as candidates by this selection; if the recovered fraction falls below 47--64%, the completeness correction is overestimated and so is $\rho_0 = 1.96 \times 10^{-6}\,\mathrm{pc}^{-3}$.

Watch

Extended reading notes

Core claim

Using 926 visually vetted carbon stars from LAMOST as the positive training sample and a random Gaia control sample, the authors train gradient-boosted decision trees (XGBoost) and a Random Forest on 133 features: Gaia colors, 110 normalized BP/RP Hermite polynomial coefficients (the compressed form of each XP spectrum), and 20 spectral indices that measure C$_2$ and CN band strengths relative to a local pseudo-continuum, deliberately excluding bands that overlap normal-star features. The intersection of the two classifiers yields 43,574 candidates across the sky. Restricting to uncrowded regions, XGProb_C $> 0.85$ (the XGBoost classification probability), and dereddened absolute magnitude $5.5 < M_G < 9.5$ leaves 627 dCs; follow-up intermediate-resolution optical spectroscopy of a random subset gives 94.8% purity for dCs with $M_G \geq 5.5$. After correcting counts for purity and for completeness (based on the fraction of the training sample recovered), the authors fit exponential and hyperbolic-secant squared density profiles in bins of disk height $z$ and find that the sech$^2$ model is strongly preferred, with $\rho_0 = 1.96 \times 10^{-6}\,\mathrm{pc}^{-3}$ and $H_z = 856$ pc. The paper states this is the first reliable measurement of the dC space density, and uses it to infer that dCs are about 2600 times rarer than G8V-K4V main-sequence stars and about 200 times more common than carbon AGB stars, implying only about 2% of C-AGB stars produce observable dCs.

Load-bearing premise

The density estimate assumes that how often the selection method re-finds the known carbon stars it was trained on (63.9% overall, 47.2% for the faint dwarfs) is the same as how completely it finds real dwarf carbon stars in the sky; the paper calls this assumption 'clearly not ideal.'

Editorial extensions

If this is right

  • Local dCs make up only about 0.03% of main-sequence stars in the same infrared absolute-magnitude range, so the measured density quantifies how rare the post-AGB mass-transfer channel is.
  • The dC space density is roughly 200 times that of carbon AGB stars, which under the paper's assumptions implies that only about 2% of C-AGB stars end up producing an observable dC companion.
  • The scale height of about 856 pc places dCs in an older, dynamically heated disk population, consistent with dCs being descendants of low-metallicity binaries with large ages.
  • The all-sky catalog adds dozens of bright ($G<14$) dCs, enabling high-resolution spectroscopy and atmospheric modeling, plus studies of variability and binarity in a uniformly selected sample.

Reading between the lines

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

  • If the completeness fraction from the classifier's self-recovery on its own training sample is optimistic, the reported $\rho_0$ would scale down roughly proportionally; an independent recovery test on a survey not used in training would resolve this.
  • The large scale height predicts that dCs should show old thick-disk kinematics; measuring radial velocities and space motions, as the authors outline, would test this prediction against the sech$^2$ vertical profile.
  • The same feature set and classifier could be pushed to fainter Gaia XP spectra, mapping the dC space density to distances beyond 5 kpc and separating disk and halo contributions, provided completeness is calibrated independently at low signal-to-noise.
  • Combining the measured dC density with a C-AGB density derived from this same catalog would sharpen the ~2% efficiency estimate and directly constrain binary population synthesis.
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Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

4 major / 6 minor

Summary. The paper presents an all-sky census of carbon stars selected from Gaia DR3 XP spectra using two supervised classifiers (XGBoost and Random Forest) trained on 926 visually vetted LAMOST carbon stars and a random Gaia control sample, yielding a catalog of 43,574 candidates. Follow-up FAST spectroscopy of 1,051 candidates provides purity estimates, and completeness is estimated from recovery of the LAMOST training sample. For 627 dC candidates with 5.5 < M_G < 9.5, XGProb_C > 0.85, |b| > 10 deg, and outside the Magellanic Cloud regions, the authors build a 1/V_max luminosity function, apply purity and completeness corrections, and fit exponential and sech^2 disk models. They report a mid-plane space density rho0 = 1.96(+0.14/-0.12) x 10^-6 pc^-3 and a scale height H_z = 856(+49/-43) pc for the sech^2 model.

Significance. If the result holds, this is the first all-sky sample of dwarf carbon stars and the first direct measurement of their local space density and disk scale height, providing an important anchor for binary population synthesis and comparisons with WDMS and C-AGB populations. The paper's strengths are its large candidate catalog, the direct spectroscopic purity assessment with 1,147 FAST spectra, the transparent 1/V_max volume framework, and the explicit acknowledgement that the completeness test on the training sample is self-referential and gives an upper limit. The central density value, however, rests on completeness corrections that are calibrated on the training set itself and on a few large-correction bins; the quoted uncertainties are purely statistical and do not include these systematics.

major comments (4)
  1. [Sec. 6.1, Table 3; Sec. 8, Table 10] The completeness correction is measured by the fraction of the LAMOST training sample recovered by the classifiers, and the authors correctly state that this is probably an upper limit on the true completeness. Because observed counts are divided by this fraction, the resulting densities in Table 10 are lower limits rather than central estimates: if field completeness for cool dCs is lower than the measured recovery rates, rho0 would be larger than reported. The MCMC uncertainties in Table 10 do not include this systematic, so the stated +0.14/-0.12 error bar understates the uncertainty in the headline density. Please state explicitly that rho0 is a lower limit under this correction and add a systematic error estimate.
  2. [Sec. 7.1, Table 7; Sec. 8] The adopted 627-star sample applies purity filter (a), XGProb_C > 0.85, but the completeness fractions in Table 3 are computed for the unfiltered XGBoost/RF overlap. Table 7 shows that filter (a) removes about 10% of the VI >= 3 candidates. The 'P+C' estimate in Table 10 therefore divides the counts of the filtered sample by the unfiltered completeness, which is not the combined purity and completeness correction claimed; it produces a lower density (1.96e-6) than the completeness-only estimate (2.04e-6). The authors should either recompute the bin-by-bin completeness after applying the XGProb cut, or correct the denominator for the retention fraction, and they should also divide by the 94.8% purity fraction from Table 9 to obtain the true dC density.
  3. [Sec. 8, Table 3] The dominant completeness correction is in the 5.5 < M_G < 6.5 bin, where only 9 of 38 training dCs are recovered (23.7%), corresponding to a correction factor of about 4.2. A modest revision of this bin's completeness from 23.7% to 20% changes the contribution of that bin by roughly 19%, comparable to or larger than the quoted +0.14e-6 uncertainty on rho0. The paper should include a sensitivity analysis in which the bin-by-bin completeness values are varied, and the resulting systematic error should be propagated into rho0 and H_z.
  4. [Sec. 8, Fig. 7] Filling the unpopulated M_G-z bins assumes that the shape of the dC luminosity function is independent of height z. While the filled bins in Figure 7 are broadly consistent with a constant shape, a luminosity-dependent scale height (for example, brighter and younger dCs closer to the plane) would bias both rho0 and H_z. Please quantify the sensitivity of the fitted parameters to this assumption, for instance by fitting the density profile using only the populated bins or by allowing the luminosity function shape to vary with z.
minor comments (6)
  1. [Abstract; Sec. 10] The abstract and summary state the result for 'dwarf carbon stars' without noting that the measurement applies only to 5.5 < M_G < 9.5; the Summary also says 626 dCs while Sections 7.1 and 8 state 627. Please harmonize these numbers and state the absolute-magnitude range in the abstract.
  2. [Sec. 6.1] The completeness of the full training sample is quoted as both 63.8% and 63.9% in successive paragraphs; 592/926 = 63.9%, so 63.8% appears to be a typo.
  3. [Sec. 3, Sec. 6] The training sample is drawn from LAMOST DR8 v2.0, while the cross-match in Section 6 uses LAMOST DR9; please clarify whether the DR9 match sample includes the DR8 training stars and whether any DR8 stars appear in the DR9 catalog.
  4. [Sec. 8, Eq. (5)] The maximum-distance calculation uses the observed G magnitude with no extinction term, while the rest of the analysis dereddens magnitudes. Please justify this choice given the |b| > 10 deg cut, or include extinction in the volume calculation for consistency.
  5. [Table 1] The C2 4382 row appears to contain an extra wavelength column, and the formatting of several rows makes the in-band and out-of-band ranges ambiguous; please reformat the table for clarity.
  6. [Sec. 6, Sec. 7] The catalog is said to be 'available on request from the authors.' For reproducibility and long-term accessibility, the training, control, and candidate tables should be deposited in a permanent archive such as CDS/VizieR or Zenodo.

Circularity Check

1 steps flagged · score 4.0 of 10

Disclosed self-referential completeness correction based on the classifier's recovery of its own LAMOST training sample is the main circular element; the space density itself rests on independent Gaia geometry and FAST spectroscopy.

  1. self definitional [Section 6.1 (Completeness), Table 3; applied in Section 8 and Table 10]
    "In fact, the best such comparison sample is our LAMOST C star training sample (see Section 3). This is clearly not ideal, because our methods should detect most of those by definition. Therefore, a completeness test on this sample probably allows an upper limit to our actual completeness."

    The completeness corrections that raise the dC counts (Sec 8, Table 10) are built from Table 3, the fraction of the LAMOST training sample recovered by the XGBoost/RF classifiers (63.9% overall; 47.2% for MG>4.5). Since the classifiers were trained on these same stars, this recovery rate is not an independent measure of field completeness; it is a self-recovery rate, as the paper acknowledges ('by definition', 'upper limit'). Because the density is obtained by dividing counts by this factor, the headline rho0 = 1.96e-6 pc^-3 inherits a self-referential input. A lower true completeness would make the density higher, so this correction is conservative for rho0, but it is still a circular calibration of the central measurement.

full rationale

The central claim is not equivalent to the training labels: it requires Gaia XP candidate selection, parallax-based distances, volume integrations, FAST spectroscopic purity checks, and model fitting to the z-profile. The one circular element is the completeness correction, which uses the classifier's recovery of its own training sample and is explicitly disclosed as an upper limit. No load-bearing self-citation chain, imported uniqueness theorem, or ansatz smuggled via citation is present. The other self-citations (Roulston et al. 2019, 2020, 2021, 2022) are contextual or methodological and do not force the density. Note also that the reader's suggestion that lower true completeness would overestimate rho0 is backwards: since counts are divided by the completeness fraction, a lower true completeness would raise, not lower, the reported density. Accordingly the circularity is partial and localized; score 4 rather than 0 because the correction feeds directly into the headline number, but not 6+ because the measurement is not forced by construction.

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

The density measurement rests on four hand-chosen analysis parameters, three domain assumptions, and one explicitly ad hoc assumption about the luminosity function shape; no new physical entities are introduced.

free parameters (4)
  • Absolute magnitude selection limits = MG in [4.5, 9.5] for dC definition; density restricted to 5.5 < MG < 9.5
    These hand-chosen cuts define which stars are counted as dwarf carbon stars; the abstract's 'local space density' excludes the 4.5-5.5 bin where selection completeness is effectively zero (Sec 8).
  • XGProb_C purity threshold = 0.85
    Applied to define the primary sample of 627 dCs; chosen to balance purity (94.8%) against loss of candidates (Sec 7.1, Table 9).
  • z-bin width = 315 pc
    Chosen by varying bin width from 100 to 750 pc to balance resolution and statistical occupancy (Sec 8).
  • Extinction law R_V = 3.1
    Assumed standard value in converting E(B-V) to Gaia extinctions, following Canbay et al. (2023); affects dereddened magnitudes and MG.
assumptions (4)
  • domain assumption MG > 4.5 identifies main-sequence dwarf carbon stars
    The paper uses an absolute magnitude cut to separate dwarfs from giants; no spectroscopic gravity measurement is used for most candidates (Sec 8).
  • domain assumption Completeness of the LAMOST training sample is representative of the C star population
    Recovery of the training sample is used to correct counts, so the training sample must be representative of the true all-sky C star population including dCs (Sec 6.1).
  • ad hoc to paper The dC luminosity function shape is constant with height z
    Missing MG bins in distant z bins are filled by scaling the nearest-z-bin luminosity function shape; the paper states this assumption explicitly (Sec 8).
  • domain assumption Bailer-Jones geometric distances and MWDUST extinction estimates are correct on average
    Distances from Bailer-Jones et al. (2021) and E(B-V) from MWDUST drive MG, z, and volume calculations (Sec 8).

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Cite this review

Pith. "Pith review of Carbon Stars From Gaia DR3 and the Space Density of Dwarf Carbon Stars." pith.science (2026). https://pith.science/paper/USWPWVQ4

@misc{pith2026250118763,
  author       = {Pith},
  title        = {Pith review of: Carbon Stars From Gaia DR3 and the Space Density of Dwarf Carbon Stars},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/USWPWVQ4}},
  note         = {Machine review of arXiv:2501.18763}
}
abstract

Carbon stars (with atmospheric C/O$>1$) range widely in temperature and luminosity, from low mass dwarfs to asymptotic giant branch stars (AGB). The main sequence dwarf carbon (dC) stars have inherited carbon-rich material from an AGB companion, which has since transitioned to a white dwarf. The dC stars are far more common than C giants, but no reliable estimates of dC space density have been published to date. We present results from an all-sky survey for carbon stars using the low-resolution XP spectra from Gaia DR3. We developed and measured a set of spectral indices contrasting C$_{\rm 2}$ and CN molecular band strengths in carbon stars against common absorption features found in normal (C/O$<1$) stars such as CaI, TiO and Balmer lines. We combined these indices with the XP spectral coefficients as input to supervised machine-learning algorithms trained on a vetted sample of known C stars from LAMOST. We describe the selection of the carbon candidate sample, and provide a catalog of 43,574 candidates dominated by cool C giants in the Magellanic Clouds and at low galactic latitude in the Milky Way. We report the confirmation of candidate C stars using intermediate ($R\sim 1800$) resolution optical spectroscopy from the Fred Lawrence Whipple Observatory, and provide estimates of sample purity and completeness. From a carefully-vetted sample of over 600 dCs, we measure their local space density to be $\rho_0\,=\,1.96^{+0.14}_{-0.12}\times10^{-6}\,\text{pc}^{-3}$ (about one dC in every local disk volume of radius 50\,pc), with a relatively large disk scale height of $H_z\,=\,856^{+49}_{-43}\,$pc.

Figures

Figures reproduced from arXiv: 2501.18763 by the authors.

Figure 1
Figure 1. The LAMOST spectrum (solid black line) and corresponding Gaia XP spectrum (orange dashed line) of a previously known carbon star, 0316+1006, or Gaia DR3 14547844505574400 (Totten & Irwin 1998; Gaia Collaboration et al. 2023). The wavelengths of major late-type stellar spectral features like the bandheads of CH, C2, CN and TiO are marked by vertical lines. We used plots like these to visually vet our C star training … view at source ↗
Figure 2
Figure 2. Importance scores of features used in XGBoost (left) and Random Forest (right), for the 20 most important features in each. Features marked (BP n) or (RP n) are the nth Hermite polynomial coefficients of the BP/RP halves of the XP spectra. Spectral indicies are shown with the central wavelength for that feature, which are listed in [PITH_FULL_IMAGE:figures/full_fig_p007_2.png] view at source ↗
Figure 3
Figure 3. presents a revised version of the main figure from Lebzelter et al. (2018), incorporating our compre￾hensive sample of C star candidates. The original plot in Lebzelter et al. (2018) was intended to distinguish between AGB stars and regions enriched in C and O el￾ements. However, a newer version of the plot in Abia et al. (2022) highlights the presence of C-rich stars in regions beyond the labeled C-rich region. By … view at source ↗
Figures from the paper (5 more)
Figure 4
Figure 4. Figure 4: Comparison of our candidate sample to our LAMOST C star training sample. UPPER LEFT: C2 λ5636 spectral index measurements vs. GBP − GRP color for our full training sample of 926 visually vetted C stars from LAMOST. UPPER RIGHT: Same plot for objects selected by our met…
Figure 5
Figure 5. Figure 5: Example of FAST spectra with Visual Inspection scores from 5 (top) to 1 (bottom). The spectra are flux-calibrated using a standard star from the same night. The Gaia spectrum for each one is overplotted in dashed orange, making it easy to see both Gaia’s much lower res…
Figure 6
Figure 6. Figure 6: The luminosity function for the closest z bin, shown also with corrections for purity, for completeness, or both. We use both for further calculations. From this luminosity function we calculated the space density as a function of z height above the disk by sum￾ming ov…
Figure 8
Figure 8. Figure 8: Posterior distributions for the model parameters ρ0, Hz, the central disk density and scale height respectively for star counts incorporating both purity and completeness corrections. Shown are the model fit results for an exponential model (a) and a hyperbolic secant …
Figure 9
Figure 9. Figure 9: Disk model fits to the density profiles of the dC candidate sample. Each data point in a z bin represents the total space density across all absolute magnitudes. We fit both an exponential model (in dark blue) and a hyperbolic secant model (in orange). For both models,…

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Works this paper leans on

102 extracted references · 19 canonical work pages

  1. [1]

    2022, A&A, 664, A45, doi: 10.1051/0004-6361/202243595 Astropy Collaboration, Robitaille, T

    Abia, C., de Laverny, P., Romero-G´ omez, M., & Figueras, F. 2022, A&A, 664, A45, doi: 10.1051/0004-6361/202243595 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

  2. [2]

    Aumer, M., & Binney, J. J. 2009, MNRAS, 397, 1286, doi: 10.1111/j.1365-2966.2009.15053.x

  3. [3]

    2021, AJ, 161, 147, doi: 10.3847/1538-3881/abd806

    Demleitner, M., & Andrae, R. 2021, AJ, 161, 147, doi: 10.3847/1538-3881/abd806

  4. [4]

    C., & Christlieb, N

    Beers, T. C., & Christlieb, N. 2005, ARA&A, 43, 531, doi: 10.1146/annurev.astro.42.053102.134057

  5. [5]

    C., Kulkarni, S

    Bellm, E. C., Kulkarni, S. R., Graham, M. J., et al. 2019, PASP, 131, 018002, doi: 10.1088/1538-3873/aaecbe

  6. [6]

    2017, MNRAS, 470, 1360, doi: 10.1093/mnras/stx1277

    Bovy, J. 2017, MNRAS, 470, 1360, doi: 10.1093/mnras/stx1277

  7. [7]

    Finkbeiner, D. P. 2016, ApJ, 818, 130, doi: 10.3847/0004-637X/818/2/130

  8. [8]

    Bovy, J., Rix, H.-W., & Hogg, D. W. 2012, ApJ, 751, 131, doi: 10.1088/0004-637X/751/2/131

Show all 102 references
  1. [9]

    L., Williams, B

    Boyer, M. L., Williams, B. F., Aringer, B., et al. 2019, ApJ, 879, 109, doi: 10.3847/1538-4357/ab24e2

  2. [10]

    Busso, M., Gallino, R., & Wasserburg, G. J. 1999, ARA&A, 37, 239, doi: 10.1146/annurev.astro.37.1.239

  3. [11]

    2023, AJ, 165, 163, doi: 10.3847/1538-3881/acbead

    Canbay, R., Bilir, S., ¨Ozd¨ onmez, A., & Ak, T. 2023, AJ, 165, 163, doi: 10.3847/1538-3881/acbead

  4. [12]

    A., Clayton, G

    Cardelli, J. A., Clayton, G. C., & Mathis, J. S. 1989, ApJ, 345, 245, doi: 10.1086/167900

  5. [13]

    M., Weiler, M., Jordi, C., et al

    Carrasco, J. M., Weiler, M., Jordi, C., et al. 2021, A&A, 652, A86, doi: 10.1051/0004-6361/202141249

  6. [14]

    P., Conroy, C., et al

    Chandra, V., Naidu, R. P., Conroy, C., et al. 2023, ApJ, 951, 26, doi: 10.3847/1538-4357/accf13

  7. [15]

    2016, arXiv e-prints, arXiv:1603.02754, doi: 10.48550/arXiv.1603.02754

    Chen, T., & Guestrin, C. 2016, arXiv e-prints, arXiv:1603.02754, doi: 10.48550/arXiv.1603.02754

  8. [16]

    J., Wisotzki, L., & Reimers, D

    Christlieb, N., Green, P. J., Wisotzki, L., & Reimers, D. 2001, A&A, 375, 366, doi: 10.1051/0004-6361:20010814

  9. [17]

    J., Kleinmann, S

    Claussen, M. J., Kleinmann, S. G., Joyce, R. R., & Jura, M. 1987, ApJS, 65, 385, doi: 10.1086/191229

  10. [18]

    2016, in Journal of Physics Conference Series, Vol

    Cristallo, S., Piersanti, L., & Straniero, O. 2016, in Journal of Physics Conference Series, Vol. 665, Journal of Physics Conference Series (IOP), 012019, doi: 10.1088/1742-6596/665/1/012019

  11. [19]

    2018, ApJ, 866, 21, doi: 10.3847/1538-4357/aadfd6

    Ramirez-Ruiz, E., & Choi, J. 2018, ApJ, 866, 21, doi: 10.3847/1538-4357/aadfd6

  12. [20]

    Hintzen, P. M. 1977, ApJ, 216, 757, doi: 10.1086/155518

  13. [21]

    C., Abrams, D

    Dalton, G., Trager, S. C., Abrams, D. C., et al. 2012, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, Vol. 8446, Ground-based and Airborne Instrumentation for Astronomy IV, ed. I. S

  14. [22]

    McLean, S. K. Ramsay, & H. Takami, 84460P, doi: 10.1117/12.925950

  15. [23]

    2024, A&A, 686, A25, doi: 10.1051/0004-6361/202348319 De Angeli, F., Weiler, M., Montegriffo, P., et al

    Dawson, H., Geier, S., Heber, U., et al. 2024, A&A, 686, A25, doi: 10.1051/0004-6361/202348319 De Angeli, F., Weiler, M., Montegriffo, P., et al. 2023, A&A, 674, A2, doi: 10.1051/0004-6361/202243680 de Jong, R. S., Bellido-Tirado, O., Chiappini, C., et al. 2012, in Society of ...

  16. [24]

    J., Liu, C., et al

    Deng, L.-C., Newberg, H. J., Liu, C., et al. 2012, Research in Astronomy and Astrophysics, 12, 735, doi: 10.1088/1674-4527/12/7/003 DESI Collaboration, Aghamousa, A., Aguilar, J., et al. 2016, arXiv e-prints, arXiv:1611.00037, doi: 10.48550/arXiv.1611.00037

  17. [25]

    Dietterich, T. G. 2000, in Multiple Classifier Systems (Berlin, Heidelberg: Springer Berlin Heidelberg), 1–15

  18. [26]

    2003, A&A, 409, 205, doi: 10.1051/0004-6361:20031070

    Drimmel, R., Cabrera-Lavers, A., & L´ opez-Corredoira, M. 2003, A&A, 409, 205, doi: 10.1051/0004-6361:20031070

  19. [27]

    2023, A&A, 674, A13, doi: 10.1051/0004-6361/202244242

    Eyer, L., Audard, M., Holl, B., et al. 2023, A&A, 674, A13, doi: 10.1051/0004-6361/202244242

  20. [28]

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

    Foreman-Mackey, D., Hogg, D. W., Lang, D., & Goodman, J. 2013, PASP, 125, 306, doi: 10.1086/670067 Gaia Collaboration, Vallenari, A., Brown, A. G. A., et al. 2023, A&A, 674, A1, doi: 10.1051/0004-6361/202243940 Garc ´ ıa-Zamora, E. M., Torres, S., & Rebassa-Mansergas, A. 2023,...

  21. [29]

    1983, MNRAS, 202, 1025, doi: 10.1093/mnras/202.4.1025

    Gilmore, G., & Reid, N. 1983, MNRAS, 202, 1025, doi: 10.1093/mnras/202.4.1025

  22. [30]

    2007, A&A, 462, 237, doi: 10.1051/0004-6361:20065249

    Girardi, L., & Marigo, P. 2007, A&A, 462, 237, doi: 10.1051/0004-6361:20065249

  23. [31]

    2010, Communications in Applied Mathematics and Computational Science, 5, 65, doi: 10.2140/camcos.2010.5.65

    Goodman, J., & Weare, J. 2010, Communications in Applied Mathematics and Computational Science, 5, 65, doi: 10.2140/camcos.2010.5.65

  24. [32]

    Gray, D. F. 2022, The Observation and Analysis of Stellar Photospheres (Cambridge University Press), doi: 10.1017/9781009082136

  25. [33]

    2013, ApJ, 765, 12, doi: 10.1088/0004-637X/765/1/12

    Green, P. 2013, ApJ, 765, 12, doi: 10.1088/0004-637X/765/1/12

  26. [34]

    J., Margon, B., Anderson, S

    Green, P. J., Margon, B., Anderson, S. F., & MacConnell, D. J. 1992, ApJ, 400, 659, doi: 10.1086/172027

  27. [35]

    J., Margon, B., & MacConnell, D

    Green, P. J., Margon, B., & MacConnell, D. J. 1991, ApJL, 380, L31, doi: 10.1086/186166

  28. [36]

    J., Montez, R., Mazzoni, F., et al

    Green, P. J., Montez, R., Mazzoni, F., et al. 2019, ApJ, 881, 49, doi: 10.3847/1538-4357/ab2bf4

  29. [37]

    T., Andersen, J., Nordstr¨ om, B., et al

    Hansen, T. T., Andersen, J., Nordstr¨ om, B., et al. 2016, A&A, 588, A3, doi: 10.1051/0004-6361/201527409

  30. [38]

    R., Millman, K

    Harris, C. R., Millman, K. J., van der Walt, S. J., et al. 2020, Array programming with NumPy, doi: 10.1038/s41586-020-2649-2

  31. [39]

    D., Katz, D., & G´ omez, A

    Haywood, M., Di Matteo, P., Lehnert, M. D., Katz, D., & G´ omez, A. 2013, A&A, 560, A109, doi: 10.1051/0004-6361/201321397

  32. [40]

    2022, Monthly Notices of the Royal Astronomical Society, 512, 1710, doi: 10.1093/mnras/stac484

    He, X.-J., Luo, A.-L., & Chen, Y.-Q. 2022, Monthly Notices of the Royal Astronomical Society, 512, 1710, doi: 10.1093/mnras/stac484

  33. [41]

    1993, A&A, 267, L31

    Heber, U., Bade, N., Jordan, S., & Voges, W. 1993, A&A, 267, L31

  34. [42]

    Hunter, J. D. 2007, Computing in Science & Engineering, 9, 90, doi: 10.1109/MCSE.2007.55

  35. [43]

    2013, ApJL, 765, L15, doi: 10.1088/2041-8205/765/1/L15

    Correnti, M. 2013, ApJL, 765, L15, doi: 10.1088/2041-8205/765/1/L15

  36. [44]

    1974, ARA&A, 12, 215, doi: 10.1146/annurev.aa.12.090174.001243

    Iben, I., J. 1974, ARA&A, 12, 215, doi: 10.1146/annurev.aa.12.090174.001243

  37. [45]

    1983, ARA&A, 21, 271, doi: 10.1146/annurev.aa.21.090183.001415

    Iben, I., J., & Renzini, A. 1983, ARA&A, 21, 271, doi: 10.1146/annurev.aa.21.090183.001415

  38. [46]

    P., Perets, H

    Igoshev, A. P., Perets, H. B., & Michaely, E. 2020, MNRAS, 494, 1448, doi: 10.1093/mnras/staa833

  39. [47]

    2021, ApJ, 919, 99, doi: 10.3847/1538-4357/ac10c5

    Iwanek, P., Soszy´ nski, I., & Koz lowski, S. 2021, ApJ, 919, 99, doi: 10.3847/1538-4357/ac10c5

  40. [48]

    G., Dermine, T., & Church, R

    Izzard, R. G., Dermine, T., & Church, R. P. 2010, A&A, 523, A10, doi: 10.1051/0004-6361/201015254

  41. [49]

    G., Jeffery, C

    Izzard, R. G., Jeffery, C. S., & Lattanzio, J. 2007, in American Institute of Physics Conference Series, Vol. 948, Unsolved Problems in Stellar Physics: A Conference in Honor of Douglas Gough, ed. R. J. Stancliffe, G. Houdek, R. G. Martin, & C. A. Tout (AIP), 51–55, doi: 10.10...

  42. [50]

    2016, ApJS, 226, 1, doi: 10.3847/0067-0049/226/1/1

    Ji, W., Cui, W., Liu, C., et al. 2016, ApJS, 226, 1, doi: 10.3847/0067-0049/226/1/1

  43. [51]

    2023, Research in Astronomy and Astrophysics, 23, 105012, doi: 10.1088/1674-4527/ace9b2

    Jia, Y., Guo, S., Zhu, C., et al. 2023, Research in Astronomy and Astrophysics, 23, 105012, doi: 10.1088/1674-4527/ace9b2

  44. [52]

    1998, A&A, 332, 877, doi: 10.48550/arXiv.astro-ph/9801272

    Jorissen, A., Van Eck, S., Mayor, M., & Udry, S. 1998, A&A, 332, 877, doi: 10.48550/arXiv.astro-ph/9801272

  45. [53]

    2016, A&A, 586, A158, doi: 10.1051/0004-6361/201526992

    Jorissen, A., Van Eck, S., Van Winckel, H., et al. 2016, A&A, 586, A158, doi: 10.1051/0004-6361/201526992

  46. [54]

    S., Marigo, P., & Tremblay, P.-E

    Kalirai, J. S., Marigo, P., & Tremblay, P.-E. 2014, ApJ, 782, 17, doi: 10.1088/0004-637X/782/1/17

  47. [55]

    I., & Lattanzio, J

    Karakas, A. I., & Lattanzio, J. C. 2014, PASA, 31, e030, doi: 10.1017/pasa.2014.21

  48. [56]

    A., Zasowski, G., Rix, H.-W., et al

    Kollmeier, J. A., Zasowski, G., Rix, H.-W., et al. 2017, arXiv e-prints, arXiv:1711.03234. https://arxiv.org/abs/1711.03234

  49. [57]

    2001, MNRAS, 322, 231, doi: 10.1046/j.1365-8711.2001.04022.x

    Kroupa, P. 2001, MNRAS, 322, 231, doi: 10.1046/j.1365-8711.2001.04022.x

  50. [58]

    2018, A&A, 616, L13, doi: 10.1051/0004-6361/201833615

    Lebzelter, T., Mowlavi, N., Marigo, P., et al. 2018, A&A, 616, L13, doi: 10.1051/0004-6361/201833615

  51. [59]

    2021, Monthly Notices of the Royal Astronomical Society, 506, 1651, doi: 10.1093/mnras/stab1650 24 Roulston et al

    Li, C., Zhang, Y., Cui, C., et al. 2021, Monthly Notices of the Royal Astronomical Society, 506, 1651, doi: 10.1093/mnras/stab1650 24 Roulston et al

  52. [60]

    2024, ApJS, 271, 12, doi: 10.3847/1538-4365/ad1881

    Li, L., Zhang, K., Cui, W., et al. 2024, ApJS, 271, 12, doi: 10.3847/1538-4365/ad1881

  53. [61]

    L., Du, C.-D., et al

    Li, Y.-B., Luo, A. L., Du, C.-D., et al. 2018, ApJS, 234, 31, doi: 10.3847/1538-4365/aaa415

  54. [62]

    D., Lesser, M., et al

    Liebert, J., Schmidt, G. D., Lesser, M., et al. 1994, ApJ, 421, 733, doi: 10.1086/173685

  55. [63]

    C., et al

    Lucatello, S., Tsangarides, S., Beers, T. C., et al. 2005, ApJ, 625, 825, doi: 10.1086/428104

  56. [64]

    2023, MNRAS, 523, 4049, doi: 10.1093/mnras/stad1675

    Lucey, M., Al Kharusi, N., Hawkins, K., et al. 2023, MNRAS, 523, 4049, doi: 10.1093/mnras/stad1675

  57. [65]

    2006, A&A, 453, 635, doi: 10.1051/0004-6361:20053842

    Picaud, S. 2006, A&A, 453, 635, doi: 10.1051/0004-6361:20053842

  58. [66]

    D., & Woodsworth, A

    McClure, R. D., & Woodsworth, A. W. 1990, ApJ, 352, 709, doi: 10.1086/168573 Nordstr¨ om, B., Mayor, M., Andersen, J., et al. 2004, A&A, 418, 989, doi: 10.1051/0004-6361:20035959 O’Brien, M. W., Tremblay, P. E., Klein, B. L., et al. 2024, MNRAS, 527, 8687, doi: 10.1093/mnras/stad3773

  59. [67]

    2000, A&AS, 143, 23, doi: 10.1051/aas:2000169

    Ochsenbein, F., Bauer, P., & Marcout, J. 2000, A&AS, 143, 23, doi: 10.1051/aas:2000169

  60. [68]

    F., G¨ ansicke, B

    Pala, A. F., G¨ ansicke, B. T., Breedt, E., et al. 2020, MNRAS, 494, 3799, doi: 10.1093/mnras/staa764

  61. [69]

    2020, MNRAS, 498, 3283, doi: 10.1093/mnras/staa2565

    Pastorelli, G., Marigo, P., Girardi, L., et al. 2020, MNRAS, 498, 3283, doi: 10.1093/mnras/staa2565

  62. [70]

    J., & Mamajek, E

    Pecaut, M. J., & Mamajek, E. E. 2013, ApJS, 208, 9, doi: 10.1088/0067-0049/208/1/9

  63. [71]

    2011, Journal of Machine Learning Research, 12, 2825

    Pedregosa, F., Varoquaux, G., Gramfort, A., et al. 2011, Journal of Machine Learning Research, 12, 2825

  64. [72]

    Plez, B., & Cohen, J. G. 2005, A&A, 434, 1117, doi: 10.1051/0004-6361:20042082

  65. [73]

    M., et al

    Rebassa-Mansergas, A., Solano, E., Jim´ enez-Esteban, F. M., et al. 2021, MNRAS, 506, 5201, doi: 10.1093/mnras/stab2039

  66. [74]

    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

  67. [75]

    W., Boubert, D., et al

    Rix, H.-W., Hogg, D. W., Boubert, D., et al. 2021, AJ, 162, 142, doi: 10.3847/1538-3881/ac0c13

  68. [76]

    R., Green, P

    Roulston, B. R., Green, P. J., & Kesseli, A. Y. 2020, ApJS, 249, 34, doi: 10.3847/1538-4365/aba1e7

  69. [77]

    R., Green, P

    Roulston, B. R., Green, P. J., Toonen, S., & Hermes, J. J. 2021, ApJ, 922, 33, doi: 10.3847/1538-4357/ac157c

  70. [78]

    R., Green, P

    Roulston, B. R., Green, P. J., Ruan, J. J., et al. 2019, ApJ, 877, 44, doi: 10.3847/1538-4357/ab1a3e

  71. [79]

    R., Green, P

    Roulston, B. R., Green, P. J., Montez, R., et al. 2022, ApJ, 926, 210, doi: 10.3847/1538-4357/ac4706

  72. [80]

    2024, gaia-dpci/GaiaXPy: GaiaXPy v2.1.2, doi: 10.5281/zenodo.11617977

    Ruz-Mieres, D., & zuzannakr. 2024, gaia-dpci/GaiaXPy: GaiaXPy v2.1.2, doi: 10.5281/zenodo.11617977

  73. [81]

    1988, ApJS, 66, 387, doi: 10.1086/191262 Science Software Branch at STScI

    Sanduleak, N., & Pesch, P. 1988, ApJS, 66, 387, doi: 10.1086/191262 Science Software Branch at STScI. 2012, PyRAF: Python alternative for IRAF

  74. [82]

    2014, Science China Physics, Mechanics, and Astronomy, 57, 176, doi: 10.1007/s11433-013-5374-0

    Si, J., Luo, A., Li, Y., et al. 2014, Science China Physics, Mechanics, and Astronomy, 57, 176, doi: 10.1007/s11433-013-5374-0

  75. [83]

    L., et al

    Si, J.-M., Li, Y.-B., Luo, A. L., et al. 2015, Research in Astronomy and Astrophysics, 15, 1671, doi: 10.1088/1674-4527/15/10/005

  76. [84]

    2023, PASP, 135, 044502, doi: 10.1088/1538-3873/acc974 Solorio-Ram ´ ırez, J.-L., Jim´ enez-Cruz, R., Villuendas-Rey, Y., & Y´ a˜ nez-M´ arquez, C

    Sithajan, S., & Meethong, S. 2023, PASP, 135, 044502, doi: 10.1088/1538-3873/acc974 Solorio-Ram ´ ırez, J.-L., Jim´ enez-Cruz, R., Villuendas-Rey, Y., & Y´ a˜ nez-M´ arquez, C. 2023, Algorithms, 16, 293, doi: 10.3390/a16060293

  77. [85]

    J., Izzard, R

    Stancliffe, R. J., Izzard, R. G., & Tout, C. A. 2005, MNRAS, 356, L1, doi: 10.1111/j.1745-3933.2005.08491.x

  78. [86]

    Stephenson, C. B. 1985, AJ, 90, 784, doi: 10.1086/113787

  79. [87]

    2023, European Physical Journal A, 59, 17, doi: 10.1140/epja/s10050-023-00926-8

    Straniero, O., Abia, C., & Dom ´ ınguez, I. 2023, European Physical Journal A, 59, 17, doi: 10.1140/epja/s10050-023-00926-8

  80. [88]

    Taylor, M. B. 2005, in Astronomical Society of the Pacific Conference Series, Vol. 347, Astronomical Data Analysis Software and Systems XIV, ed. P. Shopbell, M. Britton, & R. Ebert, 29

  81. [89]

    1986, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, Vol

    Tody, D. 1986, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, Vol. 627, Instrumentation in astronomy VI, ed. D. L. Crawford, 733, doi: 10.1117/12.968154 —. 1993, in Astronomical Society of the Pacific Conference

  82. [90]

    L., Denneau, L., Flewelling, H., et al

    Tonry, J. L., Denneau, L., Flewelling, H., et al. 2018, ApJ, 867, 105, doi: 10.3847/1538-4357/aae386

  83. [91]

    J., & Irwin, M

    Totten, E. J., & Irwin, M. J. 1998, MNRAS, 294, 1, doi: 10.1046/j.1365-8711.1998.01086.x ˇCotar, K., Zwitter, T., Kos, J., et al. 2019, MNRAS, 483, 3196, doi: 10.1093/mnras/sty3155

  84. [92]

    2020, A&A, 641, A103, doi: 10.1051/0004-6361/202038289

    Ventura, P., Dell’Agli, F., Lugaro, M., et al. 2020, A&A, 641, A103, doi: 10.1051/0004-6361/202038289

  85. [93]

    E., et al

    Virtanen, P., Gommers, R., Oliphant, T. E., et al. 2020, Nature Methods, 17, 261, doi: 10.1038/s41592-019-0686-2

  86. [94]

    Wallerstein, G., & Knapp, G. R. 1998, ARA&A, 36, 369, doi: 10.1146/annurev.astro.36.1.369

  87. [95]

    2000, A&AS, 143, 9, doi: 10.1051/aas:2000332

    Wenger, M., Ochsenbein, F., Egret, D., et al. 2000, A&AS, 143, 9, doi: 10.1051/aas:2000332

  88. [96]

    Subasavage, J. P. 2018, MNRAS, 479, 3873, doi: 10.1093/mnras/sty1622 Carbon Stars from Gaia DR3 25

  89. [97]

    P., Koposov, S

    Yao, Y., Ji, A. P., Koposov, S. E., & Limberg, G. 2023, Monthly Notices of the Royal Astronomical Society, 527, 10937, doi: 10.1093/mnras/stad3775

  90. [98]

    2019, ApJ, 887, 241, doi: 10.3847/1538-4357/ab54d0

    Yi, Z., Chen, Z., Pan, J., et al. 2019, ApJ, 887, 241, doi: 10.3847/1538-4357/ab54d0

  91. [99]

    2021, Optik, 225, 165535, doi: 10.1016/j.ijleo.2020.165535

    Yue, L., Yi, Z., Pan, J., Li, X., & Li, J. 2021, Optik, 225, 165535, doi: 10.1016/j.ijleo.2020.165535

  92. [100]

    2009, A&A, 508, 909, doi: 10.1051/0004-6361/200912843

    Zamora, O., Abia, C., Plez, B., Dom ´ ınguez, I., & Cristallo, S. 2009, A&A, 508, 909, doi: 10.1051/0004-6361/200912843

  93. [101]

    2020, ApJS, 246, 8, doi: 10.3847/1538-4365/ab5a7c

    Zhang, J., Zhang, Y., & Zhao, Y. 2020, ApJS, 246, 8, doi: 10.3847/1538-4365/ab5a7c

  94. [102]

    2012, Research in Astronomy and Astrophysics, 12, 723, doi: 10.1088/1674-4527/12/7/002

    Zhao, G., Zhao, Y.-H., Chu, Y.-Q., Jing, Y.-P., & Deng, L.-C. 2012, Research in Astronomy and Astrophysics, 12, 723, doi: 10.1088/1674-4527/12/7/002

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