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arxiv: 2606.18862 · v1 · pith:T4XG74LXnew · submitted 2026-06-17 · 🌌 astro-ph.SR

Revealing {α}-Element's Past with Subaru/IRD: Oxygen Abundance of 35 Very Metal-Poor Stars from Near-IR OH lines

Bakuh Danang Setyo Budi , Wako Aoki , Nicholas Storm , Miho Ishigaki , Tadafumi Matsuno , Teruyuki Hirano , Masayuki Kuzuhara , Jun Nishikawa
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Masashi Omiya Takayuki Kotani Tomoyuki Kudo Sebastien Vievard Motohide Tamura
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Pith reviewed 2026-06-26 19:34 UTC · model grok-4.3

classification 🌌 astro-ph.SR
keywords oxygen abundancevery metal-poor starsnear-infrared OH linesempirical calibration[O/Fe] ratioGalactic chemical evolutionSubaru/IRD
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The pith

An empirical calibration aligns near-infrared OH oxygen abundances in 35 very metal-poor stars with the forbidden [OI] line, flattening the [O/Fe] trend to match Galactic chemical evolution models.

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

This paper measures oxygen abundances for 35 very and extremely metal-poor stars using near-infrared H-band OH lines from Subaru/IRD spectra. These are compared to abundances from the optical forbidden [OI] 6300Å line in archival spectra after rederiving stellar parameters and iron abundances. A temperature-dependent offset is found between the two tracers, with OH lines being more sensitive to temperature. An empirical correction depending on effective temperature, surface gravity, iron abundance, and carbon abundance is derived to place the OH results on the [OI] scale. Applying this correction reduces scatter and temperature dependence in the [O/Fe] versus [Fe/H] diagram, producing a flatter trend that agrees with Galactic chemical evolution models.

Core claim

After homogeneously determining stellar parameters and iron abundances, the authors measure oxygen from both OH and [OI] lines via 1D/LTE spectral synthesis. They identify a systematic discrepancy that varies with temperature and derive a multi-parameter empirical calibration to align the numerous OH-based abundances onto the [OI] reference scale. Applying the correction substantially reduces scatter and temperature dependence while flattening the [O/Fe] trend, bringing the results into fairly good agreement with Galactic chemical evolution models.

What carries the argument

The multi-parameter empirical calibration (as a function of Teff, log g, [Fe/H], and [C/Fe]) that shifts 1D/LTE OH oxygen abundances onto the [OI] 6300Å reference scale.

If this is right

  • The numerous measurable NIR OH lines yield smaller random abundance errors than the single weak [OI] line once calibrated.
  • The [O/Fe] versus [Fe/H] relation for very metal-poor stars becomes flatter after correction.
  • NIR OH lines become usable for precise oxygen work in metal-poor stars when the empirical adjustment is applied.
  • The corrected abundances support consistency with predictions from Galactic chemical evolution models.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The calibration may allow oxygen measurements in additional metal-poor stars that lack suitable optical spectra for the [OI] line.
  • If the [OI] reference carries unrecognized systematics, the improved model agreement could be partly coincidental rather than a true resolution of the abundance trend.
  • The method could be extended to test whether similar corrections improve other molecular lines used in abundance studies of old stars.

Load-bearing premise

The forbidden [OI] 6300Å line provides a reliable, unbiased reference abundance scale for calibrating the OH lines.

What would settle it

Independent oxygen measurements in the same stars using 3D/NLTE models or UV OH lines that produce [O/Fe] values significantly different from the corrected NIR results would falsify the calibration's effectiveness.

Figures

Figures reproduced from arXiv: 2606.18862 by Bakuh Danang Setyo Budi, Jun Nishikawa, Masashi Omiya, Masayuki Kuzuhara, Miho Ishigaki, Motohide Tamura, Nicholas Storm, Sebastien Vievard, Tadafumi Matsuno, Takayuki Kotani, Teruyuki Hirano, Tomoyuki Kudo, Wako Aoki.

Figure 1
Figure 1. Figure 1: The non-LTE corrections of the Fe abundance from Fe I lines. Each point represents the result for an indi￾vidual Fe I line for each star, with colour-codes according to the adopted effective temperature. The upper panel shows the correction as a function of the Fe I LTE abundance, while the lower panel shows the correction as a function of the adopted surface gravity. plays a major role. For Fe II species … view at source ↗
Figure 2
Figure 2. Figure 2: The histogram distribution of Fe I (left panels) and Fe II (right panels) abundance changes corresponding to each stellar parameter: Teff on the first row, log g on the second row, and microturbulence velocity on the last row. as ∼ 10 − 20 K, which could be underestimate as Teff error; hence, for a more reasonable and conservative ap￾proach, a constant σTeff = 50 K is assumed across the sample, which is su… view at source ↗
Figure 3
Figure 3. Figure 3: Subaru/IRD spectra (black dots) of several samples (except for Arcturus) with the spectral region including several OH lines used in the analysis. The solid red line shows the best fit, with the grey shaded region representing ±0.2 dex O abundance changes to the lines. The dashed and dotted lines are the synthetic spectra without OH lines ([O/Fe] = −20) and the spectra of a rapidly rotating star (indicatin… view at source ↗
Figure 4
Figure 4. Figure 4: All archival optical spectra (black dots) of 24 samples from various instruments. The solid red line shows the best fit, with the grey shaded region representing ±0.2 dex O abundance changes to the lines. The dashed lines are synthetic spectra without [OI] lines ([O/Fe] = −20). Each x-axis minor tick mark represents a 0.25 ˚A scale [PITH_FULL_IMAGE:figures/full_fig_p015_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: The histogram distribution of [OI] line (first row) and OH lines (second row) abundance changes corresponding to each stellar parameter. parameter variations is plotted against the adopted stel￾lar parameters (see [PITH_FULL_IMAGE:figures/full_fig_p015_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: Abundance change of OH lines (red points) and [OI] line (green points) due to changes of stellar parameters as a function of input parameters. See the text for further explanation. spectively. In a typical red giant with Teff = 4500 K (D0/kB ∼ 5.1 × 103 ), a 100 K temperature increase will reduce the number of OH molecules by ∼ 25% or −0.12 dex, which is similar to what has been calculated by M. Af¸sar et … view at source ↗
Figure 7
Figure 7. Figure 7: Oxygen abundance differences between 1D/LTE H -band OH lines and optical [OI] against several parameters. Panel 1: Abundance differences are plotted for all 24 targets (including Arcturus), ordered by decreasing effective temperature from left to right. Each marker shape represents the average abundance difference derived with different instruments. Cross markers represent abundance differences after 3D/NL… view at source ↗
Figure 8
Figure 8. Figure 8: The adopted [O/Fe] versus adopted [Fe/H] plot for near-IR OH (left panel) and 6300.3 ˚A [OI] line (right panel), color-coded by effective temperature. Both oxygen abundances shown here are derived in 1D/LTE. The error bars represent the total uncertainty (σtot). The solid red line represents the average solar-neighborhood chemical evolution model for oxygen taken from C. Kobayashi et al. (2020). Blue color… view at source ↗
Figure 9
Figure 9. Figure 9: Upper left panel: Corrected OH-based [O/Fe] ratios for the complete sample of 35 stars, overlaid with a linear regression fit (gray dashed line). The solid blue line represents the Galactic chemical evolution of oxygen (K20: C. Kobayashi et al. 2020). For comparison, the uncorrected [O/Fe] ratios are shown as fainter data points, with their corresponding linear fit indicated by a faint gray dashed line. Bo… view at source ↗
Figure 10
Figure 10. Figure 10: Same description as [PITH_FULL_IMAGE:figures/full_fig_p027_10.png] view at source ↗
Figure 11
Figure 11. Figure 11: Same description as [PITH_FULL_IMAGE:figures/full_fig_p027_11.png] view at source ↗
Figure 12
Figure 12. Figure 12: Plot of O abundance (A(O)) derived from both OH and [OI] lines as a function of line strength for Arcturus (upper panel) and HD 122563 (lower panel). The error bar in each data point represents the uncertainty due to the input atmospheric parameters: σatm. The mean abundance for each tracer is indicated as a dotted horizontal line. For the OH lines (cross), each data point represents a different line. For… view at source ↗
Figure 13
Figure 13. Figure 13: The literature and derived stellar parameters and O abundances for Arcturus and HD 122563. For Teff, log g, and [Fe/H], the Y-axis shows the differences between each literature source and the adopted values. Half-filled data points represent the O abundance derived using stellar parameters from R. Collet et al. (2018). The lower legends are given for the O abundance panels only. (PE93: R. C. Peterson et a… view at source ↗
Figure 14
Figure 14. Figure 14: Example of the 3D/LTE correction (∆3L 1L ≡ A(O)3D/LTE − A(O)1D/LTE) derived in this works (show as color-coded map) for [O/Fe]=0.75 dex (upper panel) and 1.50 dex (lower dex) for various Fe and C abundances. In each subplot, X and Y-axes are effective temperature and surface gravity respectively [PITH_FULL_IMAGE:figures/full_fig_p030_14.png] view at source ↗
read the original abstract

Oxygen abundances in very and extremely metal-poor (V/EMP) stars provide critical constraints on early massive stars' nucleosynthesis. An Oxygen abundance analysis is presented for 35 V/EMP stars (-4.0<[Fe/H]< -1.5) using near-infrared H-band OH vibro-rotational lines from high-resolution Subaru/IRD spectra. To examine the reliability of these NIR OH lines, the results are compared with the abundances obtained from the 3D/NLTE-insensitive forbidden [OI] 6300{\AA} line using archival high-resolution optical spectra. After homogeneously rederiving stellar parameters and 1D/NLTE Fe abundances using Gaia photo-astrometry and literature optical Fe equivalent width data, oxygen abundance from OH and [OI] lines is determined through 1D/LTE spectral synthesis. A sensitivity analysis confirms that near-IR OH lines are highly sensitive to the adopted temperature compared to the forbidden line. A temperature-dependent discrepancy between the tracers is identified: in cool red giants (Teff <4600 K), OH-based abundances are systematically lower than [OI]-based abundance by 0.05 to 0.25 dex, while warmer red giants show higher OH-based abundances as expected from 3D effects. Despite this systematic offset, the numerous measurable NIR OH lines yield significantly smaller random abundance errors than that of the single, weak [OI] line. Leveraging this statistical precision, an empirical calibration as a function of Teff, log g, [Fe/H], and [C/Fe] is derived to align the 1D/LTE OH abundances onto the [OI] scale. Applying this correction substantially reduces the scatter and temperature dependence in the [O/Fe] versus [Fe/H] plane and flattens the trend, bringing the results into fairly good agreement with Galactic chemical evolution models.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

1 major / 0 minor

Summary. The paper measures oxygen abundances for 35 very metal-poor stars (-4.0 < [Fe/H] < -1.5) using near-IR H-band OH vibro-rotational lines from Subaru/IRD spectra. After rederiving stellar parameters and 1D/NLTE Fe abundances, 1D/LTE abundances are derived from both OH lines and the forbidden [OI] 6300Å line. A temperature-dependent offset is identified between the tracers, and a 4-parameter empirical calibration (Teff, log g, [Fe/H], [C/Fe]) is derived from the OH-[OI] differences within the sample to align the OH abundances onto the [OI] scale. Application of this correction reduces scatter and temperature dependence in the [O/Fe] vs [Fe/H] plane and improves agreement with Galactic chemical evolution models.

Significance. If the calibration is demonstrated to be robust and generalizable, the work would be significant because the numerous OH lines offer substantially smaller random errors than the single weak [OI] line, enabling tighter constraints on oxygen yields from early massive stars. The identification of the temperature-dependent discrepancy and the statistical advantage of OH lines are clear strengths.

major comments (1)
  1. Abstract: the empirical calibration is derived 'to align the 1D/LTE OH abundances onto the [OI] scale' from the differences within these same 35 stars and is then applied to the identical sample to claim reduced scatter, removal of temperature dependence, and improved model agreement. Because the fit is constructed to minimize exactly those differences, the reported improvements are at risk of being tautological; the manuscript must demonstrate that the functional form is physically motivated and generalizes via cross-validation, hold-out tests, or an external sample.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for their constructive review and for highlighting the need to demonstrate that the empirical calibration generalizes beyond the fitting sample. We agree this is an important point and will revise the manuscript accordingly.

read point-by-point responses

  1. Referee: Abstract: the empirical calibration is derived 'to align the 1D/LTE OH abundances onto the [OI] scale' from the differences within these same 35 stars and is then applied to the identical sample to claim reduced scatter, removal of temperature dependence, and improved model agreement. Because the fit is constructed to minimize exactly those differences, the reported improvements are at risk of being tautological; the manuscript must demonstrate that the functional form is physically motivated and generalizes via cross-validation, hold-out tests, or an external sample.

    Authors: We acknowledge the validity of this concern. The calibration is indeed derived from the same 35-star sample, so the reported reductions in scatter and temperature dependence could partly reflect the fitting process itself. The four-parameter form was selected because the sensitivity analysis already showed that the OH-[OI] offset correlates strongly with Teff (and secondarily with log g, [Fe/H], and [C/Fe]), providing a physical basis rather than an arbitrary choice. Nevertheless, to demonstrate generalization we will add a leave-one-out cross-validation analysis in the revised manuscript, reporting the typical prediction error on held-out stars. We will also expand the discussion of the physical motivation for the chosen parameters. We do not have an independent external sample with both OH and [OI] measurements, so cross-validation is the route we will pursue. revision: yes

Circularity Check

1 steps flagged

Empirical 4-parameter calibration fitted to OH-[OI] differences in the 35-star sample then applied to the same sample to reduce scatter

specific steps
  1. fitted input called prediction [Abstract]
    "Leveraging this statistical precision, an empirical calibration as a function of Teff, log g, [Fe/H], and [C/Fe] is derived to align the 1D/LTE OH abundances onto the [OI] scale. Applying this correction substantially reduces the scatter and temperature dependence in the [O/Fe] versus [Fe/H] plane and flattens the trend, bringing the results into fairly good agreement with Galactic chemical evolution models."

    The calibration coefficients are obtained by fitting to the observed OH minus [OI] abundance differences within the identical 35-star sample; applying the resulting function to those same stars necessarily shrinks the residuals (scatter, temperature trend) by construction, rendering the reported improvement tautological absent independent validation.

full rationale

The paper derives an empirical correction (function of Teff, log g, [Fe/H], [C/Fe]) explicitly 'to align the 1D/LTE OH abundances onto the [OI] scale' using differences measured in the analyzed stars, then reports that applying the correction 'substantially reduces the scatter and temperature dependence' and improves model agreement. This matches the fitted_input_called_prediction pattern: the improvement is the direct statistical consequence of minimizing the very offsets used to construct the fit, with no cross-validation, hold-out set, or external sample cited to demonstrate generalization beyond the input data.

Axiom & Free-Parameter Ledger

1 free parameters · 2 axioms · 0 invented entities

The central claim rests on the assumption that the [OI] line provides an unbiased reference scale and that a four-parameter empirical function fitted to the observed offset can be applied generally; no independent evidence for the calibration's universality is supplied in the abstract.

free parameters (1)
  • coefficients of the empirical calibration function
    The calibration is derived as a function of Teff, log g, [Fe/H], and [C/Fe] to align OH to [OI]; the coefficients are necessarily fitted to the 35-star sample.
axioms (2)
  • domain assumption The forbidden [OI] 6300Å line is insensitive to 3D and NLTE effects and therefore serves as the ground-truth reference.
    Stated in the abstract as the basis for the comparison and subsequent calibration.
  • domain assumption 1D/LTE spectral synthesis is adequate once an empirical correction is applied.
    The analysis uses 1D/LTE synthesis for both tracers and then corrects the OH results empirically.

pith-pipeline@v0.9.1-grok · 5955 in / 1736 out tokens · 30520 ms · 2026-06-26T19:34:29.537721+00:00 · methodology

discussion (0)

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Works this paper leans on

119 extracted references · 114 canonical work pages · 4 internal anchors

  1. [1]

    2016, ApJ, 819, 103, doi: 10.3847/0004-637X/819/2/103

    Af¸ sar, M., Sneden, C., Frebel, A., et al. 2016, ApJ, 819, 103, doi: 10.3847/0004-637X/819/2/103

    work page doi:10.3847/0004-637x/819/2/103 2016

  2. [2]

    M., Asplund, M., Collet, R., & Leenaarts, J

    Amarsi, A. M., Asplund, M., Collet, R., & Leenaarts, J. 2016a, MNRAS, 455, 3735, doi: 10.1093/mnras/stv2608

    work page doi:10.1093/mnras/stv2608

  3. [3]

    M., Liljegren, S., & Nissen, P

    Amarsi, A. M., Liljegren, S., & Nissen, P. E. 2022, A&A, 668, A68, doi: 10.1051/0004-6361/202244542

    work page doi:10.1051/0004-6361/202244542 2022

  4. [4]

    2016b, MNRAS, 463, 1518, doi: 10.1093/mnras/stw2077

    Collet, R. 2016b, MNRAS, 463, 1518, doi: 10.1093/mnras/stw2077

    work page doi:10.1093/mnras/stw2077

  5. [5]

    Barklem, P. S. 2019a, A&A, 622, L4, doi: 10.1051/0004-6361/201834480 32

    work page doi:10.1051/0004-6361/201834480

  6. [6]

    M., Nissen, P

    Amarsi, A. M., Nissen, P. E., & Sk´ ulad´ ottir,´A. 2019b, A&A, 630, A104, doi: 10.1051/0004-6361/201936265

    work page doi:10.1051/0004-6361/201936265

  7. [7]

    2015, ApJ, 811, 64, doi: 10.1088/0004-637X/811/1/64

    Aoki, W. 2015, ApJ, 811, 64, doi: 10.1088/0004-637X/811/1/64

    work page doi:10.1088/0004-637x/811/1/64 2015

  8. [8]

    2018, PASJ, 70, 94, doi: 10.1093/pasj/psy092

    Aoki, W., Matsuno, T., Honda, S., et al. 2018, PASJ, 70, 94, doi: 10.1093/pasj/psy092

    work page doi:10.1093/pasj/psy092 2018

  9. [9]

    E., Ryan, S

    Aoki, W., Norris, J. E., Ryan, S. G., Beers, T. C., & Ando, H. 2002, ApJ, 567, 1166, doi: 10.1086/338756

    work page doi:10.1086/338756 2002

  10. [10]

    C., et al

    Aoki, W., Honda, S., Beers, T. C., et al. 2007, ApJ, 660, 747, doi: 10.1086/512601

    work page doi:10.1086/512601 2007

  11. [11]

    C., Sivarani, T., et al

    Aoki, W., Beers, T. C., Sivarani, T., et al. 2008, ApJ, 678, 1351, doi: 10.1086/533517

    work page doi:10.1086/533517 2008

  12. [12]

    C., Honda, S., et al

    Aoki, W., Beers, T. C., Honda, S., et al. 2022, PASJ, 74, 273, doi: 10.1093/pasj/psab123

    work page doi:10.1093/pasj/psab123 2022

  13. [13]

    C., Honda, S., et al

    Aoki, W., Beers, T. C., Honda, S., et al. 2025, PASJ, psaf017, doi: 10.1093/pasj/psaf017

    work page doi:10.1093/pasj/psaf017 2025

  14. [14]

    2019, A&A, 621, A108, doi: 10.1051/0004-6361/201834146

    Arentsen, A., Starkenburg, E., Shetrone, M.-D., et al. 2019, A&A, 621, A108, doi: 10.1051/0004-6361/201834146

    work page doi:10.1051/0004-6361/201834146 2019

  15. [15]

    Asplund, M., & Garc´ ıa P´ erez, A. E. 2001, A&A, 372, 601, doi: 10.1051/0004-6361:20010483

    work page doi:10.1051/0004-6361:20010483 2001

  16. [16]

    Asplund, M., Nordlund, ˚A., Trampedach, R., & Stein, R. F. 1999, A&A, 346, L17, doi: 10.48550/arXiv.astro-ph/9905059 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 As...

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.48550/arxiv.astro-ph/9905059 1999

  17. [17]

    C., & Carney, B

    Balachandran, S. C., & Carney, B. W. 1996, AJ, 111, 946, doi: 10.1086/117842

    work page doi:10.1086/117842 1996

  18. [18]

    2003, ApJ, 588, 1072, doi: 10.1086/374312

    Barbuy, B., Mel´ endez, J., Spite, M., et al. 2003, ApJ, 588, 1072, doi: 10.1086/374312

    work page doi:10.1086/374312 2003

  19. [19]

    2024,, Astrophysics Source Code Library, record ascl:2407.001 http://ascl.net/2407.001

    Barlow, T. 2024,, Astrophysics Source Code Library, record ascl:2407.001 http://ascl.net/2407.001

    2024

  20. [20]

    C., & Christlieb, N

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

    work page doi:10.1146/annurev.astro.42.053102.134057 2005

  21. [21]

    2012, MNRAS, 427, 1344, doi: 10.1111/j.1365-2966.2012.22008.x

    Bergemann, M., Lind, K., Collet, R., Magic, Z., & Asplund, M. 2012, MNRAS, 427, 27, doi: 10.1111/j.1365-2966.2012.21687.x

    work page doi:10.1111/j.1365-2966.2012.21687.x 2012

  22. [22]

    2014, in Determination of Atmospheric Parameters of B, ed

    Bergemann, M., & Nordlander, T. 2014, in Determination of Atmospheric Parameters of B, ed. E. Niemczura, B. Smalley, & W. Pych, 169–185, doi: 10.1007/978-3-319-06956-2 16

    work page doi:10.1007/978-3-319-06956-2 2014

  23. [23]

    2021, MNRAS, 508, 2236, doi: 10.1093/mnras/stab2160

    Bergemann, M., Hoppe, R., Semenova, E., et al. 2021, MNRAS, 508, 2236, doi: 10.1093/mnras/stab2160

    work page doi:10.1093/mnras/stab2160 2021

  24. [24]

    2014, A&A, 569, A111, doi: 10.1051/0004-6361/201423945

    Blanco-Cuaresma, S., Soubiran, C., Heiter, U., & Jofr´ e, P. 2014, A&A, 569, A111, doi: 10.1051/0004-6361/201423945

    work page doi:10.1051/0004-6361/201423945 2014

  25. [25]

    Bonifacio, P., Monai, S., & Beers, T. C. 2000, AJ, 120, 2065, doi: 10.1086/301566

    work page doi:10.1086/301566 2000

  26. [26]

    2026, ApJ, 997, 203, doi: 10.3847/1538-4357/ae27a1

    Tennyson, J. 2026, ApJ, 997, 203, doi: 10.3847/1538-4357/ae27a1

    work page doi:10.3847/1538-4357/ae27a1 2026

  27. [27]

    Brooke, J. S. A., Bernath, P. F., Western, C. M., et al. 2016, JQSRT, 168, 142, doi: 10.1016/j.jqsrt.2015.07.021

    work page doi:10.1016/j.jqsrt.2015.07.021 2016

  28. [28]

    2018, ApJ, 864, 43, doi: 10.3847/1538-4357/aad37d

    Cain, M., Frebel, A., Gull, M., et al. 2018, ApJ, 864, 43, doi: 10.3847/1538-4357/aad37d

    work page doi:10.3847/1538-4357/aad37d 2018

  29. [29]

    A., Clayton, G

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

    work page doi:10.1086/167900 1989

  30. [30]

    S., et al

    Casagrande, L., Portinari, L., Glass, I. S., et al. 2014, MNRAS, 439, 2060, doi: 10.1093/mnras/stu089

    work page doi:10.1093/mnras/stu089 2014

  31. [31]

    2004, A&A, 416, 1117, doi: 10.1051/0004-6361:20034074

    Cayrel, R., Depagne, E., Spite, M., et al. 2004, A&A, 416, 1117, doi: 10.1051/0004-6361:20034074

    work page doi:10.1051/0004-6361:20034074 2004

  32. [32]

    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

    work page internal anchor Pith review doi:10.3847/0004-637x/823/2/102 2016

  33. [33]

    2007, A&A, 469, 687, doi: 10.1051/0004-6361:20066321

    Collet, R., Asplund, M., & Trampedach, R. 2007, A&A, 469, 687, doi: 10.1051/0004-6361:20066321

    work page doi:10.1051/0004-6361:20066321 2007

  34. [34]

    2018, MNRAS, 475, 3369, doi: 10.1093/mnras/sty002

    Trampedach, R. 2018, MNRAS, 475, 3369, doi: 10.1093/mnras/sty002

    work page doi:10.1093/mnras/sty002 2018

  35. [35]

    2000, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, Vol

    Kotzlowski, H. 2000, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, Vol. 4008, Optical and IR Telescope Instrumentation and Detectors, ed. M. Iye & A. F. Moorwood, 534–545, doi: 10.1117/12.395512

    work page doi:10.1117/12.395512 2000

  36. [36]

    2015, A&A, 576, A128, doi: 10.1051/0004-6361/201424885

    Dobrovolskas, V., Kuˇ cinskas, A., Bonifacio, P., et al. 2015, A&A, 576, A128, doi: 10.1051/0004-6361/201424885

    work page doi:10.1051/0004-6361/201424885 2015

  37. [37]

    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

    work page internal anchor Pith review doi:10.3847/0067-0049/222/1/8 2016

  38. [38]

    F., & Steffen, M

    Mello, G. F., & Steffen, M. 2016, A&A, 585, A75, doi: 10.1051/0004-6361/201526783

    work page doi:10.1051/0004-6361/201526783 2016

  39. [39]

    2024, A&A, 688, A52, doi: 10.1051/0004-6361/202348448

    Eitner, P., Bergemann, M., Hoppe, R., et al. 2024, A&A, 688, A52, doi: 10.1051/0004-6361/202348448

    work page doi:10.1051/0004-6361/202348448 2024

  40. [40]

    2009, A&A, 500, 1143, doi: 10.1051/0004-6361/200810095 Fernandes de Melo, R., Lombardo, L., Alencastro Puls, A., et al

    Akerman, C. 2009, A&A, 500, 1143, doi: 10.1051/0004-6361/200810095 Fernandes de Melo, R., Lombardo, L., Alencastro Puls, A., et al. 2024, A&A, 691, A220, doi: 10.1051/0004-6361/202451173

    work page doi:10.1051/0004-6361/200810095 2009

  41. [41]

    Fulbright, J. P. 2000, AJ, 120, 1841, doi: 10.1086/301548

    work page doi:10.1086/301548 2000

  42. [42]

    P., & Johnson, J

    Fulbright, J. P., & Johnson, J. A. 2003, ApJ, 595, 1154, doi: 10.1086/377443 Gaia Collaboration, Babusiaux, C., van Leeuwen, F., et al. 2018, A&A, 616, A10, doi: 10.1051/0004-6361/201832843 Gaia Collaboration, Vallenari, A., Brown, A. G. A., et al. 2023, A&A, 674, A1, doi: 10.1051/0004-6361/202243940 33

    work page doi:10.1086/377443 2003

  43. [43]

    J., Caffau, E., Bonifacio, P., et al

    Gallagher, A. J., Caffau, E., Bonifacio, P., et al. 2016, A&A, 593, A48, doi: 10.1051/0004-6361/201628602

    work page doi:10.1051/0004-6361/201628602 2016

  44. [44]

    M., Magg, E., Plez, B., et al

    Gerber, J. M., Magg, E., Plez, B., et al. 2023, A&A, 669, A43, doi: 10.1051/0004-6361/202243673

    work page doi:10.1051/0004-6361/202243673 2023

  45. [45]

    2008, A&A, 486, 951, doi: 10.1051/0004-6361:200809724

    Gustafsson, B., Edvardsson, B., Eriksson, K., et al. 2008, A&A, 486, 951, doi: 10.1051/0004-6361:200809724

    work page doi:10.1051/0004-6361:200809724 2008

  46. [46]

    T., Holmbeck, E

    Hansen, T. T., Holmbeck, E. M., Beers, T. C., et al. 2018, ApJ, 858, 92, doi: 10.3847/1538-4357/aabacc

    work page doi:10.3847/1538-4357/aabacc 2018

  47. [47]

    2011, A&A, 529, A158, doi: 10.1051/0004-6361/201015782

    Hayek, W., Asplund, M., Collet, R., & Nordlund, ˚A. 2011, A&A, 529, A158, doi: 10.1051/0004-6361/201015782

    work page doi:10.1051/0004-6361/201015782 2011

  48. [48]

    2021, A&A, 645, A106, doi: 10.1051/0004-6361/201936291

    Heiter, U., Lind, K., Bergemann, M., et al. 2021, A&A, 645, A106, doi: 10.1051/0004-6361/201936291

    work page doi:10.1051/0004-6361/201936291 2021

  49. [49]

    1995, PASP, 107, 1042, doi: 10.1086/133660

    Hinkle, K., Wallace, L., & Livingston, W. 1995, PASP, 107, 1042, doi: 10.1086/133660

    work page doi:10.1086/133660 1995

  50. [50]

    H., & Lambert, D

    Hinkle, K. H., & Lambert, D. L. 1975, MNRAS, 170, 447, doi: 10.1093/mnras/170.3.447 Høg, E., Fabricius, C., Makarov, V. V., et al. 2000, A&A, 355, L27

    work page doi:10.1093/mnras/170.3.447 1975

  51. [51]

    K., Frebel, A., Roederer, I

    Hollek, J. K., Frebel, A., Roederer, I. U., et al. 2011, ApJ, 742, 54, doi: 10.1088/0004-637X/742/1/54

    work page doi:10.1088/0004-637x/742/1/54 2011

  52. [52]

    M., Beers, T

    Holmbeck, E. M., Beers, T. C., Roederer, I. U., et al. 2018, ApJL, 859, L24, doi: 10.3847/2041-8213/aac722

    work page doi:10.3847/2041-8213/aac722 2018

  53. [53]

    A., Shetrone, M., Johnson, J

    Holtzman, J. A., Shetrone, M., Johnson, J. A., et al. 2015, AJ, 150, 148, doi: 10.1088/0004-6256/150/5/148

    work page doi:10.1088/0004-6256/150/5/148 2015

  54. [54]

    C., & Takada-Hidai, M

    Honda, S., Aoki, W., Beers, T. C., & Takada-Hidai, M. 2011, ApJ, 730, 77, doi: 10.1088/0004-637X/730/2/77

    work page doi:10.1088/0004-637x/730/2/77 2011

  55. [55]

    2004, ApJ, 607, 474, doi: 10.1086/383406

    Honda, S., Aoki, W., Kajino, T., et al. 2004, ApJ, 607, 474, doi: 10.1086/383406

    work page doi:10.1086/383406 2004

  56. [56]

    2024, The Astrophysical Journal, 975, 19, doi: 10.3847/1538-4357/ad7110

    Huber, D., Slumstrup, D., Hon, M., et al. 2024, The Astrophysical Journal, 975, 19, doi: 10.3847/1538-4357/ad7110

    work page doi:10.3847/1538-4357/ad7110 2024

  57. [57]

    N., Aoki, W., & Chiba, M

    Ishigaki, M. N., Aoki, W., & Chiba, M. 2013, ApJ, 771, 67, doi: 10.1088/0004-637X/771/1/67

    work page doi:10.1088/0004-637x/771/1/67 2013

  58. [58]

    N., Chiba, M., & Aoki, W

    Ishigaki, M. N., Chiba, M., & Aoki, W. 2012, ApJ, 753, 64, doi: 10.1088/0004-637X/753/1/64

    work page doi:10.1088/0004-637x/753/1/64 2012

  59. [59]

    2016, in IOS Press, 87–90, doi: 10.3233/978-1-61499-649-1-87

    Kluyver, T., Ragan-Kelley, B., P´ erez, F., et al. 2016, in IOS Press, 87–90, doi: 10.3233/978-1-61499-649-1-87

    work page doi:10.3233/978-1-61499-649-1-87 2016

  60. [60]

    I., & Lugaro, M

    Kobayashi, C., Karakas, A. I., & Lugaro, M. 2020, ApJ, 900, 179, doi: 10.3847/1538-4357/abae65

    work page doi:10.3847/1538-4357/abae65 2020

  61. [61]

    2018, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, Vol

    Kotani, T., Tamura, M., Nishikawa, J., et al. 2018, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, Vol. 10702, Ground-based and Airborne Instrumentation for Astronomy VII, ed. C. J

    2018

  62. [62]

    Simard, & H

    Evans, L. Simard, & H. Takami, 1070211, doi: 10.1117/12.2311836

    work page doi:10.1117/12.2311836

  63. [63]

    P., Suntzeff, N

    Kraft, R. P., Suntzeff, N. B., Langer, G. E., et al. 1982, PASP, 94, 55, doi: 10.1086/130941

    work page doi:10.1086/130941 1982

  64. [64]

    C., & Weiss, W

    Stempels, H. C., & Weiss, W. W. 2000, Baltic Astronomy, 9, 590, doi: 10.1515/astro-2000-0420

    work page doi:10.1515/astro-2000-0420 2000

  65. [65]

    K., Johnson, J

    Lai, D. K., Johnson, J. A., Bolte, M., & Lucatello, S. 2007, ApJ, 667, 1185, doi: 10.1086/520949

    work page doi:10.1086/520949 2007

  66. [66]

    2022, ApJ, 931, 147, doi: 10.3847/1538-4357/ac6514

    Li, H., Aoki, W., Matsuno, T., et al. 2022, ApJ, 931, 147, doi: 10.3847/1538-4357/ac6514

    work page doi:10.3847/1538-4357/ac6514 2022

  67. [67]

    N., Ludwig, H

    Li, H. N., Ludwig, H. G., Caffau, E., Christlieb, N., & Zhao, G. 2013, ApJ, 765, 51, doi: 10.1088/0004-637X/765/1/51

    work page doi:10.1088/0004-637x/765/1/51 2013

  68. [68]

    Lind, K., & Amarsi, A. M. 2024, ARA&A, 62, 475, doi: 10.1146/annurev-astro-052722-103557

    work page doi:10.1146/annurev-astro-052722-103557 2024

  69. [69]

    2022, A&A, 661, A140, doi: 10.1051/0004-6361/202142971

    Magg, E., Bergemann, M., Serenelli, A., et al. 2022, A&A, 661, A140, doi: 10.1051/0004-6361/202142971

    work page doi:10.1051/0004-6361/202142971 2022

  70. [70]

    2013, A&A, 557, A26, doi: 10.1051/0004-6361/201321274

    Magic, Z., Collet, R., Asplund, M., et al. 2013, A&A, 557, A26, doi: 10.1051/0004-6361/201321274

    work page doi:10.1051/0004-6361/201321274 2013

  71. [71]

    2025, The Astrophysical Journal, 986, 144, doi: 10.3847/1538-4357/add0b4

    Marasco, C., Tayar, J., & Nidever, D. 2025, The Astrophysical Journal, 986, 144, doi: 10.3847/1538-4357/add0b4

    work page doi:10.3847/1538-4357/add0b4 2025

  72. [72]

    2011, A&A, 528, A87, doi: 10.1051/0004-6361/201015336

    Grupp, F. 2011, A&A, 528, A87, doi: 10.1051/0004-6361/201015336

    work page doi:10.1051/0004-6361/201015336 2011

  73. [73]

    2017, A&A, 608, A89, doi: 10.1051/0004-6361/201731582

    Mashonkina, L., Jablonka, P., Sitnova, T., Pakhomov, Y., & North, P. 2017, A&A, 608, A89, doi: 10.1051/0004-6361/201731582

    work page doi:10.1051/0004-6361/201731582 2017

  74. [74]

    2003, The Messenger, 114, 20 Mel´ endez, J., & Barbuy, B

    Mayor, M., Pepe, F., Queloz, D., et al. 2003, The Messenger, 114, 20 Mel´ endez, J., & Barbuy, B. 2002, ApJ, 575, 474, doi: 10.1086/341142 Mel´ endez, J., Barbuy, B., & Spite, F. 2001, ApJ, 556, 858, doi: 10.1086/321624

    work page doi:10.1086/341142 2003

  75. [75]

    2024, A&A, 687, A229, doi: 10.1051/0004-6361/202449816

    Mishenina, T., Pignatari, M., Usenko, I., et al. 2024, A&A, 687, A229, doi: 10.1051/0004-6361/202449816

    work page doi:10.1051/0004-6361/202449816 2024

  76. [76]

    Mittal, S., & Roederer, I. U. 2025, AJ, 169, 172, doi: 10.3847/1538-3881/adadf0

    work page doi:10.3847/1538-3881/adadf0 2025

  77. [77]

    Morton, T. D. 2015,, Astrophysics Source Code Library, record ascl:1503.010 http://ascl.net/1503.010

    2015

  78. [78]

    2021, A&A, 653, A90, doi: 10.1051/0004-6361/202140979

    Mucciarelli, A., Bellazzini, M., & Massari, D. 2021, A&A, 653, A90, doi: 10.1051/0004-6361/202140979

    work page doi:10.1051/0004-6361/202140979 2021

  79. [79]

    2002, PASJ, 54, 855, doi: 10.1093/pasj/54.6.855

    Noguchi, K., Aoki, W., Kawanomoto, S., et al. 2002, PASJ, 54, 855, doi: 10.1093/pasj/54.6.855

    work page doi:10.1093/pasj/54.6.855 2002

  80. [80]

    2013, ARA&A, 51, 457, doi: 10.1146/annurev-astro-082812-140956

    Nomoto, K., Kobayashi, C., & Tominaga, N. 2013, ARA&A, 51, 457, doi: 10.1146/annurev-astro-082812-140956

    work page doi:10.1146/annurev-astro-082812-140956 2013

Showing first 80 references.