Pith. sign in

REVIEW 4 major objections 5 minor 64 references

SDSS J102915.14+172927.9: Revisiting the chemical pattern

T0 review · 4 major / 5 minor · reviewed 2026-08-12 · deepseek-v4-flash

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

Pith's one-line read Reanalysing new and archival UVES spectra, this paper establishes a stricter carbon upper limit for the ultra metal-poor star SDSS J102915+172927, confirming it is not carbon-enhanced and is the most metal-poor object known.

desk verdict A careful re-analysis with genuinely better data, but the non-CEMP claim rests on a slimmer margin than the headline suggests. read the letter →

arxiv 2411.13096 v1 pith:IKRBYGNQ submitted 2024-11-20 astro-ph.GA

E. Caffau (GEPI) , P. Bonifacio (GEPI) , L. Monaco (UNAB) , M. Steffen (AIP) , L. Sbordone (ESO) , M. Spite (GEPI) , P. François (GEPI) , A J Gallagher (AIP)
show 2 more authors
H.-G. Ludwig (LSW) P. Molaro (OAT)
This is my paper · ORCID
classification astro-ph.GA
keywords stars:abundancesPopulationIIIIIgalaxy:evolutionformationultrametal-poorstarcarbon-enhanced
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 seeks to settle how the ultra metal-poor star SDSS J102915+172927 formed by tightening its carbon abundance upper limit. Using new and archival high-resolution spectra, the authors derive a 3-$\sigma$ limit of A(C) < 4.68, making the star the only one at [Fe/H] < -4.5 that is not carbon-enhanced. This places a cap on the total metallicity of Z < 1.915 x 10^(-6), more than twenty times lower than the most iron-poor star previously known. The authors therefore conclude that the gas cloud that formed this star could not have cooled through atomic lines, and must have cooled through dust or fragmented directly from near-primordial material.

What carries the argument

The load-bearing technique is the derivation of a 3-sigma upper limit on carbon from the G-band CH molecular lines in a combined high-resolution spectrum of doubled signal-to-noise. The strongest CH features are compared with synthetic spectra computed from 1D LTE model atmospheres, with the noise floor set by a standard equivalent-width detection formula; a -0.53 dex correction, computed from 3D hydrodynamical model atmospheres whose temperature stratification is cooler in the line-forming region, is then applied to convert the 1D limit to 3D. The same machinery, a curve-of-growth interpolation of 3-sigma equivalent widths, is used to set upper limits on Na, Al, Sr, and Ba. The argument depends on the order merging and pseudo-normalization of the G-band region being free of subtle flux-calibration errors.

What would settle it

An independent spectrum with even higher S/N that detects the CH G-band at $A(\mathrm{C}) > 5.1$ would overturn the paper's central conclusion, as would a verified competing analysis that places $A(\mathrm{C})$ above 5.0 and below 5.1 while confirming the higher value.

Watch

Extended reading notes

Core claim

The paper's central claim is that SDSS J102915+172927 is genuinely not enhanced in carbon. Fitting the strongest CH features of the G-band in a combined spectrum with doubled signal-to-noise yields a 3-$\sigma$ upper limit of A(C) < 4.68, corresponding to [C/Fe] < 0.91 in 1D-LTE and < 0.26 after applying a -0.53 dex correction from 3D hydrodynamical model atmospheres. This places the star below the CEMP threshold of [C/Fe] > 1.0 and, with a total metallicity Z < 1.915 x 10^(-6), makes it the most metal-poor object known to date. Since the transition discriminant D < -3.71, the authors conclude that atomic-line cooling was insufficient to form a low-mass star in this gas, and that dust cooling or fragmentation of the primordial cloud are the viable channels. The paper also reports a tentative detection of the lithium doublet at A(Li) = 1.08, well below the Spite plateau.

Load-bearing premise

The conclusion rests on the reliability of the -0.53 dex three-dimensional correction applied to the carbon upper limit; if that correction is overestimated, the star could be carbon-enhanced and its formation could be explained by atomic-line cooling after all.

Editorial extensions

If this is right

  • SDSS J102915+172927 becomes the most metal-poor object known, with a metallicity cap more than twenty times lower than the previous record holder.
  • It is the only star at [Fe/H] < -4.5 that does not satisfy the [C/Fe] > 1 CEMP criterion, making it a unique test case for dust-cooled low-mass star formation.
  • The tentative lithium detection at A(Li) = 1.08, far below the Spite plateau, supports the idea that the star formed from lithium-poor gas or subsequently depleted its lithium.
  • The star's prograde, low-eccentricity disc orbit combined with its extreme metal poverty raises the possibility of a Pop III star polluted during its long journey through the Galactic disc.
  • If dust cooling is confirmed, the result constrains the dust-to-gas ratio and grain properties needed to form low-mass stars at metallicities near 10^(-6) Z_sun.

Reading between the lines

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

  • It would follow, though the paper does not say so, that the absence of carbon enhancement is not a decisive obstacle to forming low-mass stars in the early Universe; dust or fragmentation must be able to operate at metallicities near $10^{-6}\,Z_{\odot}$.
  • The apparent conflict with the competing analysis that allows $A(\mathrm{C}) < 5.39$ suggests that the CEMP classification of this star is not yet settled, and that an independent higher-S/N observation of the G-band or an independent 3D non-LTE calculation would be the cleanest way to break the tie.
  • If the tentative lithium detection at $A(\mathrm{Li}) = 1.08$ is real, it would add the star to a small set of ultra metal-poor stars whose lithium is below the Spite plateau, pointing to early lithium depletion rather than preservation of the primordial value.
  • The disc-like orbit combined with extreme metal poverty hints that the low-mass first stars may have formed in the disc as well as the halo, which would change how searches for Pop III survivors are designed.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

4 major / 5 minor

Summary. The paper presents a new analysis of the ultra metal-poor star SDSS J102915.14+172927.9 based on newly obtained high-resolution UVES spectra combined with archival data. The authors derive abundances for Mg, Si, Ca, Ti, Fe, Ni, and a tentative Li detection, plus upper limits for C, Na, Al, Sr, and Ba. The central claims are that the carbon abundance is A(C) < 4.68, that the star is therefore not carbon-enhanced and is the only star at [Fe/H] < -4.5 outside the CEMP class, and that the resulting metallicity upper limit Z < 1.915e-6 implies formation through dust cooling rather than atomic-line cooling. The paper carefully validates the order merging against Gaia XP spectra, checks radial-velocity stability, and tests the tentative Li feature against individual observations.

Significance. If the central claims hold, this star is a unique observational anchor for the transition from the first to the second stellar generations: it would be the most metal-poor object known and the only non-carbon-enhanced star at [Fe/H] < -4.5, supporting dust-cooled or fragmentation-based formation scenarios. The paper has clear strengths: the new spectra approximately double the S/N in the G-band region, the data reduction and velocity corrections are carefully described, and the Li feature is checked against individual exposures. However, the headline non-CEMP conclusion rests on a thin 1D-LTE margin of only 0.09 dex in [C/Fe], with the final margin supplied by a model-dependent 3D correction. The manuscript is therefore scientifically important but requires additional robustness analysis before the central claim can be considered established.

major comments (4)
  1. [Sec. 4.5 and Table 1] The central claim that the star is not carbon-enhanced rests on a very thin 1D-LTE margin. The 1D-LTE upper limit [C/Fe] < 0.91 is only 0.09 dex below the Beers & Christlieb threshold [C/Fe] > 1.0, and the comfortable final margin comes from applying the -0.53 dex 3D correction. The paper should provide a sensitivity analysis showing how [C/Fe] and the CEMP classification change if the 3D correction is reduced by, say, 0.2 dex or if a CH NLTE correction near the +0.2 dex value quoted in the same section is adopted. As written, the non-CEMP conclusion is not robust to these plausible systematic shifts.
  2. [Sec. 4.5] The rejection of the Lagae et al. (2023) carbon upper limit (A(C) < 5.25-5.39) is based on a methodological preference for localized strong CH features over a wider-range chi-square fit, not on a direct spectral comparison using the same stacked data. Given that the difference is about 0.7 dex and that the Lagae value would place the star in a CEMP-compatible regime, the authors should show that the Lagae et al. synthetic spectra are excluded by the new, higher-S/N spectrum in the G-band region, or quantify the fit statistic for both methods on the same normalization.
  3. [Sec. 5] The metallicity upper limit Z < 1.915e-6 and the transition discriminant D depend directly on the assumed scaling of unmeasured nitrogen and oxygen with the carbon upper limit and on the 3D carbon correction. Because D < -3.71 in 1D is only about 0.2 dex below Dcrit = -3.5 +/- 0.2, the dust-cooling conclusion is not secure without a sensitivity analysis that varies the O/C scaling and the carbon correction over the plausible ranges discussed in Sec. 4.5.
  4. [Sec. 5] The statement that SDSS J102915+172927 is 'the only star with [Fe/H] < -4.5 not satisfying [C/Fe] > 1' is presented immediately after noting that Pristine J221.8781+09.7844 also has no measurable G-band but only a loose upper limit ([C/Fe] < 2.3). The paper should clarify whether that loose upper limit formally places the Pristine star in the CEMP class; otherwise the uniqueness claim is not established.
minor comments (5)
  1. [Abstract and Sec. 4.4] The abstract says abundances for seven elements were derived, while Sec. 4.4 says six elements; the discrepancy should be reconciled (the tentative Li likely accounts for the difference).
  2. [Introduction and Table 1] The introduction states Lagae et al. (2023) derived A(C) < 5.39, while Table 1 lists their 1D-LTE upper limit as A(C)L < 5.25; the difference should be explained or corrected.
  3. [Sec. 4.5] The text gives two carbon upper limits, A(C) < 4.71 from the fit and A(C) < 4.68 from the curve-of-growth method, but does not explicitly state which value is adopted in Table 1 and why.
  4. [Sec. 4.4] The Na i line at 588.9 nm is the D2 line, not the D1 line; please correct the nomenclature.
  5. [Sec. 4.4] The statement that the star is 'surely under-abundant in Sr' is stronger than the 3-sigma upper-limit methodology supports; a more measured phrasing would be appropriate.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: the carbon upper limit and non-CEMP classification are derived from new spectra and standard line-formation modeling, not from the conclusions they support.

full rationale

The derivation chain is self-contained on the key claim. The carbon upper limit A(C)<4.68 comes from fitting the CH G-band in new, higher-S/N UVES spectra using ATLAS12/SYNTHE and Cayrel's formula (Sec. 4.5), an independent measurement rather than a renaming of the conclusion. The non-CEMP classification follows from comparing the 1D-LTE [C/Fe]<0.91 with the Beers & Christlieb (2005) threshold of [C/Fe]>1.0; this does not require the 3D correction, which is only used to strengthen the margin. The 3D correction itself is computed in this paper with CO5BOLD and Linfor3D (Fig. 12), not merely imported; the Gallagher et al. (2016) citation is supporting rather than load-bearing. The adopted NLTE corrections from Caffau et al. (2012) affect iron and other elements, but the quoted [Fe/H]=-4.73 and the [C/Fe] upper limit use the 1D-LTE Fe value, and the Z upper limit explicitly relies on 1D-LTE abundances (Sec. 5), so these self-citations do not carry the central inference. The dust-cooling interpretation is benchmarked against external theoretical work (Schneider et al. 2012; Klessen et al. 2012; Omukai et al. 2005) and the transition discriminant D is compared to the independent D_crit from Frebel et al. (2007). The disagreement with Lagae et al. (2023) is addressed by methodology and improved S/N, not by circular reasoning. No fitted parameter is renamed as a prediction, and no equation reduces to its own input. Consequently, no circularity is present.

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

The central carbon upper limit rests on the CH line data, the adopted model atmospheres, and an abundance-dependent 3D correction; the headline Z and D values rest on scaling unmeasured elements, especially O, to the carbon limit. No invented entities appear. The abundance scale also depends on assumed microturbulence and adopted NLTE corrections from the authors' prior work.

free parameters (6)
  • Microturbulence xi = 1 km/s
    Adopted by assumption in Sec 4.2 because too few Fe I lines of varying strength exist to derive it; it enters the curve-of-growth abundance scale for all elements.
  • Extinction A_V = 0.08
    Adopted from a private communication (Rosine Lallement, Sec 4.2) and used in the synthetic-color Teff derivation; a 0.05 dex gravity and 6 K temperature sensitivity to the parallax zero-point correction is noted.
  • 3D carbon correction = -0.53 dex (at A(C) = 4.5)
    Applied to the 1D-LTE carbon upper limit in Sec 4.5; the correction is model-derived and abundance-dependent (-0.72 dex at A(C) = 5.75), yet propagated as a constant into the final [C/Fe] < 0.26.
  • Fe NLTE correction = +0.12 dex
    Adopted from Caffau et al. (2012) and Bergemann et al. (2012) in Sec 4.4; literature alternatives are +0.25 (Lagae et al. 2023) and +0.4 (Ezzeddine et al. 2017), and the choice is motivated in part by the fact that a larger correction would make the star alpha-poor.
  • Oxygen abundance for D and Z = scaled to the C upper limit
    In Sec 5, N and O are set by scaling with the carbon upper limit because O is unmeasured; the transition discriminant D and the metallicity Z depend directly on this choice.
  • Stellar mass = 0.65 M_sun
    Converged from MIST, BASTI, and Chieffi-FRANEC isochrones in Sec 4.2; enters the gravity via the Stefan-Boltzmann relation.
assumptions (5)
  • domain assumption CH G-band line data (Masseron et al. 2014) and NH line data (Fernando et al. 2018) are complete and accurate.
    Sec 4.5 and Sec 4.4; the carbon and nitrogen limits are computed against these molecular line lists, and no independent verification of the lists is provided.
  • domain assumption The ATLAS12 1D model and CO5BOLD 3D models (Teff = 5780 K, log g = 4.60 or 4.70, [M/H] = -4.0) represent the photosphere well enough that the derived 3D correction applies to this star.
    Sec 3 and Sec 4.5; the conclusion that 3D CH lines are stronger by about 0.5 dex is model-based, and the 3D correction is cited to Gallagher et al. (2016), a paper by the same team.
  • domain assumption Gaia DR3 parallax and photometry give the correct stellar parameters after the Lindegren et al. (2021) zero-point correction, and the star is a main-sequence dwarf.
    Sec 4.2; the main-sequence classification rules out the gravitational-settling scenario of MacDonald et al. (2013).
  • ad hoc to paper Unmeasured elements are solar-scaled, with N and O scaled with C, when computing Z and D.
    Sec 5; this choice is specific to this paper and directly determines the headline Z < 1.915e-6 and D < -3.71.
  • domain assumption The photospheric composition, after considering the accretion pollution discussed in Sec 5, reflects the natal cloud, so the low Z constrains the formation cooling mechanism.
    Sec 5; the paper itself raises the Pop III accretion-pollution alternative, which would change the formation inference from dust cooling to H2/Ly-alpha cooling.

how reviews work

0 comments
Cite this review

Pith. "Pith review of SDSS J102915.14+172927.9: Revisiting the chemical pattern." pith.science (2026). https://pith.science/paper/IKRBYGNQ

@misc{pith2026241113096,
  author       = {Pith},
  title        = {Pith review of: SDSS J102915.14+172927.9: Revisiting the chemical pattern},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/IKRBYGNQ}},
  note         = {Machine review of arXiv:2411.13096}
}
abstract

Context: The small- to intermediate-mass ($M <0.8 M_\odot$), most metal-poor stars that formed in the infancy of the Universe are still shining today in the sky. They are very rare, but their discovery and investigation brings new knowledge on the formation of the first stellar generations. Aims: SDSS J102915.14+172927.9 is one of the most metal-poor star known to date. Since no carbon can be detected in its spectrum, a careful upper limit is important, both to classify this star and to distinguish it from the carbon-enhanced stars that represent the majority at these metallicities. Methods: We undertook a new observational campaign to acquire high-resolution UVES spectra. The new spectra were combined with archival spectra in order to increase the signal-to-noise ratio. From the combined spectrum, we derived abundances for seven elements (Mg, Si, Ca, Ti, Fe, Ni, and a tentative Li) and five significant upper limits (C, Na, Al, Sr, and Ba). Results: The star has a carbon abundance A(C) <4.68 and therefore is not enhanced in carbon, at variance with the majority of the stars at this Fe regime, which typically show A(C)> 6.0. A feature compatible with the Li doublet at 670.7 nm is tentatively detected. Conclusions: The upper limit on carbon implies $Z<1.915 \times 10^{-6}$, more than 20 times lower than the most iron-poor star known. Therefore, the gas cloud out of which the star was formed did not cool via atomic lines but probably through dust. Fragmentation of the primordial cloud is another possibility for the formation of a star with a metallicity this low.

Figures

Figures reproduced from arXiv: 2411.13096 by the authors.

Figure 1
Figure 1. Combined observed spectrum flux calibrated in the wavelength range of Ca ii-K and -H. The two interstellar components are labelled as IS. The H line and few metallic lines (Fe i) are visible. vective overshoot is emerging naturally. For the stellar parame￾ters considered here, the temperature of the 3D model is cooler than predicted by the corresponding 1D model for optical depths log τRoss < −2.0, whereas the tempe… view at source ↗
Figure 2
Figure 2. Three-dimensional versus 1D temperature structure for stel￾lar parameters Teff=5773 K, log g=4.7, and metallicity [M/H]=−4.0. The orange band outlines the 3D temperature distribution of the high￾resolution model resampled to 70 × 70 × 160 grid points. The width of the temperature distribution encountered on surfaces of equal Rosse￾land optical depth is indicated by the dashed blue lines enclosing 95,5% of the data p… view at source ↗
Figure 3
Figure 3. shows the SDSS J102915+172927 orbit in X, Y, and Z rectangular Galactocentric coordinates (bottom-left, bottom￾right and upper-left panels). The current position of the star is in￾dicated as a black solid star. SDSS J102915+172927 lies at a dis￾tance of 1.47±0.13 kpc from the Sun and of 8.72±0.07 kpc from the Galactic centre, 1.24 ± 0.11 kpc above the Galactic plane. Its orbit is pro-grade, confined within Zmax = 2.… view at source ↗
Figures from the paper (8 more)
Figure 4
Figure 4. Figure 4: Observed spectrum (solid black) in the wavelength of the Na i D1 line compared to a synthesis (solid red) with A(Na) derived from Cayrel’s formula multiplied by a factor 3. The S/N of 85 is highlighted by the dashed blue lines [PITH_FULL_IMAGE:figures/full_fig_p005_4.png]
Figure 5
Figure 5. Figure 5: Observed spectrum (solid black) in the wavelength of the 349.9 nm Al i line compared to a synthesis (solid red) with A(Al) from the upper limit. The S/N of 85 is highlighted by the dashed blue lines. less stringent (see [PITH_FULL_IMAGE:figures/full_fig_p005_5.png]
Figure 6
Figure 6. Figure 6: Observed spectrum (solid black) in the wavelength of the 407.7 nm Sr ii line compared to a synthesis (solid red) with A(Sr) from the upper limit. The S/N of 90 ratio is highlighted by the dashed blue lines. concentrated on the determination of an upper limit for C. We …
Figure 8
Figure 8. Figure 8: Observed spectra (solid black) in the wavelength of the 670.7 nm Li i doublet compared to synthesis (solid red and blue). The 1σ S/N is highlighted by the dashed blue lines. tures, we derived values in the range: 3.60 < A(C) < 4.23. In the wavelength range around 432 n…
Figure 9
Figure 9. Figure 9: Observed spectra (solid black) in the wavelength of the G-band compared to the best fit (solid red) and a synthesis (solid green) to vi￾sualise the strongest CH features. The S/N is highlighted by the dashed blue lines. The visible strong line is Fe i. and 430 nm, we f…
Figure 10
Figure 10. Figure 10: , and the upper limit we derived at 3σ is A(C) < 4.68, which provides [C/H] < −3.82 and [C/Fe] < 0.91 with the 1D￾LTE Fe value from [PITH_FULL_IMAGE:figures/full_fig_p007_10.png]
Figure 11
Figure 11. Figure 11: EW contribution function, dW/d log τRoss for three of the strongest CH features in the G-band, located at 4293 Å (dashed), 4303 Å (solid), and 4327 Å (dash-dotted), respectively, as computed from the 3D model shown in [PITH_FULL_IMAGE:figures/full_fig_p008_11.png]
Figure 12
Figure 12. Figure 12: Synthetic 3D profile (solid black, EW=1.57 pm) compared to the 1D synthesis (solid red, EW=0.44 pm) of the CH feature at 429 nm in the case of A(C)=4.75. We note that the carbon feature is a blend of several components, such that it appears asymmetric even in the 1D s…

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

64 extracted references · 33 canonical work pages

  1. [1]

    S., González Hernández, J

    Aguado, D. S., González Hernández, J. I., Allende Prieto, C., & Rebolo, R. 2019, ApJ, 874, L21

    work page 2019

  2. [2]

    S., Molaro, P., Caffau, E., et al

    Aguado, D. S., Molaro, P., Caffau, E., et al. 2022, A&A, 668, A86

    work page 2022

  3. [3]

    M., & Grevesse, N

    Asplund, M., Amarsi, A. M., & Grevesse, N. 2021, A&A, 653, A141

    2021

  4. [4]

    Beers, T. C. & Christlieb, N. 2005, ARA&A, 43, 531

    2005

  5. [5]

    Bensby, T., Feltzing, S., & Oey, M. S. 2014, A&A, 562, A71

    2014

  6. [6]

    M., et al

    Bergemann, M., Collet, R., Amarsi, A. M., et al. 2017, ApJ, 847, 15

    2017

  7. [7]

    2012, MNRAS, 427, 27

    Bergemann, M., Lind, K., Collet, R., Magic, Z., & Asplund, M. 2012, MNRAS, 427, 27

    2012

  8. [8]

    2024, A&A, 684, A91

    Bonifacio, P., Caffau, E., Monaco, L., et al. 2024, A&A, 684, A91

    work page 2024

Show all 64 references
  1. [9]

    2015, A&A, 579, A28

    Bonifacio, P., Caffau, E., Spite, M., et al. 2015, A&A, 579, A28

    2015

  2. [10]

    2018, Research Notes of the American Astronomical Society, 2, 19

    Bonifacio, P., Caffau, E., Spite, M., et al. 2018, Research Notes of the American Astronomical Society, 2, 19

    2018

  3. [11]

    2021, A&A, 651, A79

    Bonifacio, P., Monaco, L., Salvadori, S., et al. 2021, A&A, 651, A79

    2021

  4. [12]

    Bovino, S., Grassi, T., Schleicher, D. R. G., & Banerjee, R. 2016, ApJ, 832, 154

    2016

  5. [13]

    C., et al

    Bovy, J., Allende Prieto, C., Beers, T. C., et al. 2012, ApJ, 759, 131

    2012

  6. [14]

    2013, Reports on Progress in Physics, 76, 112901

    Bromm, V . 2013, Reports on Progress in Physics, 76, 112901

    2013

  7. [15]

    & Loeb, A

    Bromm, V . & Loeb, A. 2003, Nature, 425, 812

    2003

  8. [16]

    2013, A&A, 560, A15

    Caffau, E., Bonifacio, P., François, P., et al. 2013, A&A, 560, A15

    2013

  9. [17]

    2012, A&A, 542, A51

    Caffau, E., Bonifacio, P., François, P., et al. 2012, A&A, 542, A51

    2012

  10. [18]

    2024, A&A, 684, L4

    Caffau, E., Bonifacio, P., Monaco, L., et al. 2024, A&A, 684, L4

    2024

  11. [19]

    1988, in The Impact of Very High S /N Spectroscopy on Stellar Physics, ed

    Cayrel, R. 1988, in The Impact of Very High S /N Spectroscopy on Stellar Physics, ed. G. Cayrel de Strobel & M. Spite, V ol. 132, 345

    1988

  12. [20]

    2004, A&A, 416, 1117

    Cayrel, R., Depagne, E., Spite, M., et al. 2004, A&A, 416, 1117

    2004

  13. [21]

    2014, MNRAS, 439, 3121

    Chiaki, G., Schneider, R., Nozawa, T., et al. 2014, MNRAS, 439, 3121

    2014

  14. [22]

    2016, ApJ, 823, 102

    Choi, J., Dotter, A., Conroy, C., et al. 2016, ApJ, 823, 102

    2016

  15. [23]

    S., Beers, T

    Christlieb, N., Bessell, M. S., Beers, T. C., et al. 2002, Nature, 419, 904

    2002

  16. [24]

    Deshmukh, S. A. & Ludwig, H. G. 2023, A&A, 675, A146 Di Matteo, P., Spite, M., Haywood, M., et al. 2020, A&A, 636, A115

    2023

  17. [25]

    A., Sestito, F., et al

    Dovgal, A., Venn, K. A., Sestito, F., et al. 2024, MNRAS, 527, 7810

    2024

  18. [26]

    2017, ApJ, 847, 142

    Ezzeddine, R., Frebel, A., & Plez, B. 2017, ApJ, 847, 142

    2017

  19. [27]

    2018, A&A, 618, A141

    Ezzeddine, R., Merle, T., Plez, B., et al. 2018, A&A, 618, A141

    2018

  20. [28]

    M., Bernath, P

    Fernando, A. M., Bernath, P. F., Hodges, J. N., & Masseron, T. 2018, J. Quant. Spectr. Rad. Transf., 217, 29 François, P., Depagne, E., Hill, V ., et al. 2007, A&A, 476, 935

    2018

  21. [29]

    L., & Bromm, V

    Frebel, A., Johnson, J. L., & Bromm, V . 2007, MNRAS, 380, L40

    2007

  22. [30]

    G., et al

    Freytag, B., Steffen, M., Ludwig, H. G., et al. 2012, Journal of Computational Physics, 231, 919 Gaia Collaboration, Montegriffo, P., Bellazzini, M., et al. 2023a, A&A, 674, A33 Gaia Collaboration, Vallenari, A., Brown, A. G. A., et al. 2023b, A&A, 674, A1

    2012

  23. [31]

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

    Gallagher, A. J., Caffau, E., Bonifacio, P., et al. 2016, A&A, 593, A48

    2016

  24. [32]

    H., Glover, S

    Greif, T. H., Glover, S. C. O., Bromm, V ., & Klessen, R. S. 2010, ApJ, 716, 510

    2010

  25. [33]

    C., Carollo, D., & Lee, Y

    Hattori, K., Yoshii, Y ., Beers, T. C., Carollo, D., & Lee, Y . S. 2014, ApJ, 784, 153

    2014

  26. [34]

    L., Pietrinferni, A., Cassisi, S., et al

    Hidalgo, S. L., Pietrinferni, A., Cassisi, S., et al. 2018, ApJ, 856, 125

    2018

  27. [35]

    Johnson, J. L. 2015, MNRAS, 453, 2771

    2015

  28. [36]

    C., Bessell, M

    Keller, S. C., Bessell, M. S., Frebel, A., et al. 2014, Nature, 506, 463

    2014

  29. [37]

    Klessen, R. S. & Glover, S. C. O. 2023, ARA&A, 61, 65

    2023

  30. [38]

    S., Glover, S

    Klessen, R. S., Glover, S. C. O., & Clark, P. C. 2012, MNRAS, 421, 3217

    2012

  31. [39]

    Kurucz, R. L. 2005, Memorie della Societa Astronomica Italiana Supplementi, 8, 14

    2005

  32. [40]

    M., Rodríguez Díaz, L

    Lagae, C., Amarsi, A. M., Rodríguez Díaz, L. F., et al. 2023, A&A, 672, A90

    2023

  33. [41]

    2021, MNRAS, 508, 3068

    Lardo, C., Mashonkina, L., Jablonka, P., et al. 2021, MNRAS, 508, 3068

    2021

  34. [42]

    2022, ApJ, 931, 147

    Li, H., Aoki, W., Matsuno, T., et al. 2022, ApJ, 931, 147

    2022

  35. [43]

    2021, A&A, 649, A4

    Lindegren, L., Bastian, U., Biermann, M., et al. 2021, A&A, 649, A4

    2021

  36. [44]

    Lodders, K., Palme, H., & Gail, H. P. 2009, Landolt B&ouml;rnstein, 4B, 712

    2009

  37. [45]

    2021, A&A, 656, A155

    Lombardo, L., François, P., Bonifacio, P., et al. 2021, A&A, 656, A155

    2021

  38. [46]

    M., Anilmis, N., & Rufo, N

    MacDonald, J., Lawlor, T. M., Anilmis, N., & Rufo, N. F. 2013, Monthly Notices of the Royal Astronomical Society, 431, 1425

    2013

  39. [47]

    2014, A&A, 571, A47

    Masseron, T., Plez, B., Van Eck, S., et al. 2014, A&A, 571, A47

    2014

  40. [48]

    2022, A&A, 661, A153

    Mucciarelli, A., Monaco, L., Bonifacio, P., et al. 2022, A&A, 661, A153

    2022

  41. [49]

    2005, ApJ, 626, 627

    Omukai, K., Tsuribe, T., Schneider, R., & Ferrara, A. 2005, ApJ, 626, 627

    2005

  42. [50]

    2021, ApJ, 908, 102

    Pietrinferni, A., Hidalgo, S., Cassisi, S., et al. 2021, ApJ, 908, 102

    2021

  43. [51]

    A., Hoppe, R., Bergemann, M., et al

    Popa, S. A., Hoppe, R., Bergemann, M., et al. 2023, A&A, 670, A25

    2023

  44. [52]

    2018, adrn/pyia: v0.2

    Price-Whelan, A. 2018, adrn/pyia: v0.2

    2018

  45. [53]

    2014, A&A, 564, A109

    Sbordone, L., Caffau, E., Bonifacio, P., & Duffau, S. 2014, A&A, 564, A109

    2014

  46. [54]

    2012, MNRAS, 423, L60 Schönrich, R., Binney, J., & Dehnen, W

    Schneider, R., Omukai, K., Limongi, M., et al. 2012, MNRAS, 423, L60 Schönrich, R., Binney, J., & Dehnen, W. 2010, MNRAS, 403, 1829

    2012

  47. [55]

    F., et al

    Sestito, F., Longeard, N., Martin, N. F., et al. 2019, MNRAS, 484, 2166

    2019

  48. [56]

    M., Mashonkina, L

    Sitnova, T. M., Mashonkina, L. I., Ezzeddine, R., & Frebel, A. 2019, MNRAS, 485, 3527

    2019

  49. [57]

    M., Mashonkina, L

    Sitnova, T. M., Mashonkina, L. I., & Ryabchikova, T. A. 2016, MNRAS, 461, 1000

    2016

  50. [58]

    D., Wise, J

    Smith, B. D., Wise, J. H., O’Shea, B. W., Norman, M. L., & Khochfar, S. 2015, MNRAS, 452, 2822

    2015

  51. [59]

    2005, A&A, 430, 655

    Spite, M., Cayrel, R., Plez, B., et al. 2005, A&A, 430, 655

    2005

  52. [60]

    & Spite, F

    Spite, M. & Spite, F. 1982, Nature, 297, 483

    1982

  53. [61]

    S., Bonifacio, P., et al

    Starkenburg, E., Aguado, D. S., Bonifacio, P., et al. 2018, MNRAS, 481, 3838

    2018

  54. [62]

    Steffen, M., Ludwig, H.-G., Wedemeyer-Böhm, S., & Gallagher, A. J. 2024, Lin- for3D User Manual http://www.aip.de/Members/msteffen/linfor3d

    2024

  55. [63]

    O., Kirby, E

    Thygesen, A. O., Kirby, E. N., Gallagher, A. J., et al. 2017, ApJ, 843, 144

    2017

  56. [64]

    1981, A&A, 97, 280 Article number, page 9 of 10 A&A proofs: manuscript no

    Yoshii, Y . 1981, A&A, 97, 280 Article number, page 9 of 10 A&A proofs: manuscript no. aa52079-24corr Appendix A: Lines used In Table A.1, the atomic lines investigated are listed. Table A.1. Atomic data. Element λ log g f Elow [nm] cm −1 Na i 588.9951 0 .108 0.0 Mg i 382.9355...

    1981

Pith tools

Reviewed August 12, 2026 · model on record in the stance chip above.