Pith. sign in

REVIEW 2 major objections 5 minor 112 references

The $Hubble$ Missing Globular Cluster Survey. I. Survey overview and the first precise age estimate for ESO452-11 and 2MASS-GC01

T0 review · 2 major / 5 minor · reviewed 2026-08-09 · deepseek-v4-flash

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

Pith's one-line read Deep Hubble images give two clusters their first precise ages, and one is surprisingly young.

desk verdict A solid survey-overview paper whose ESO452-11 age is credible and whose 2MASS-GC01 age is honestly conditional on future reddening work. read the letter →

arxiv 2502.01741 v2 pith:GJKF5KPR submitted 2025-02-03 astro-ph.GA

D. Massari , M. Bellazzini , M. Libralato , A. Bellini , E. Dalessandro , E. Ceccarelli , F. Aguado-Agelet , S. Cassisi
show 12 more authors
C. Gallart M. Monelli A. Mucciarelli E. Pancino M. Salaris S. Saracino E. Dodd F. R. Ferraro E. R. Garro B. Lanzoni R. Pascale L. Rosignoli
This is my paper · ORCID
classification astro-ph.GA
keywords globularclustersopenstellaragescolour-magnitudediagramsHubbleSpaceTelescopeisochronefittingdifferentialreddeningMilkyWaydisk
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 presents the first precise age measurements for two poorly studied Milky Way star clusters, made possible by new deep Hubble Space Telescope images that reach several magnitudes below each cluster's main-sequence turn-off. For ESO452-11, at the edge of the bulge, the isochrone fit gives an age of $13.59^{+0.48}_{-0.69}$ Gyr at $[\mathrm{M/H}]\simeq-0.80$, placing it among the old in-situ globular clusters. For 2MASS-GC01, hidden behind heavy disc dust and observed in the near-infrared, the fit gives an age of $7.22^{+0.93}_{-1.11}$ Gyr at $[\mathrm{M/H}]\simeq-0.73$, which would make it either the youngest globular cluster known or a massive, compact open cluster. The paper therefore establishes two concrete age anchors and raises the question of whether 2MASS-GC01's classification should be revised.

What carries the argument

The machinery is the CARMA isochrone-fitting procedure as applied to deep HST colour-magnitude diagrams. A mean ridge line is defined on the differential-reddening-corrected CMD, stars near the ridge are selected, and a grid of solar-scaled BaSTI stellar models is fitted via MCMC sampling with loose priors on metallicity, distance, and colour excess, yielding posterior distributions for age, $[\mathrm{M/H}]$, $E(B-V)$, and distance modulus. Differential reddening is mapped and corrected following the method of Milone et al. (2012), which is essential for both clusters but especially for the heavily extincted 2MASS-GC01. The two clusters are fitted independently in the two CMD planes, with the final values taken as the average of the two runs and uncertainties encompassing both; the key enabling data are the new photometry reaching roughly two magnitudes below the main-sequence turn-off.

What would settle it

A direct test would be near-infrared spectroscopy of a dozen red giants in 2MASS-GC01 to measure iron and alpha-element abundances: globular-cluster-like alpha enhancement and a light-element spread would argue against a plain open-cluster interpretation, while solar-scaled abundances would support one. Alternatively, measuring the age from a reddening-free indicator, such as the red-clump luminosity or the white-dwarf cooling sequence, would bypass the differential-reddening problem that dominates the current uncertainty.

Watch

Extended reading notes

Core claim

The central discovery is that deep two-band photometry can pin down the ages of clusters that were previously only barely resolved, and that one of them, 2MASS-GC01, is surprisingly young for a globular cluster. After correcting for differential reddening, the authors fit BaSTI stellar models to the ridge lines of the colour-magnitude diagrams in two independent planes, obtaining mutually consistent solutions for ESO452-11 and a young solution for 2MASS-GC01. The age difference is large: 2MASS-GC01 is about 6.5 Gyr younger than ESO452-11 at similar metallicity, and its nearly circular, thin-disc orbit supports an in-situ, disc origin. The authors conclude that 2MASS-GC01 is either a young globular cluster unlike any other or an extreme open cluster, and they defer a firm classification until spectroscopic abundances are available.

Load-bearing premise

For 2MASS-GC01, the entire young-age conclusion rests on the assumption that the differential-reddening correction, applied at an extreme mean extinction of $E(B-V)=7.27$, adequately removes the effects of patchy foreground dust, even though the paper itself states that the photometry still suffers from severe residual differential reddening.

Editorial extensions

If this is right

  • If 2MASS-GC01 is as young as found, it becomes either the youngest globular cluster known in the Milky Way or the first massive compact open cluster at its metallicity.
  • ESO452-11's age of 13.6 Gyr at $[\mathrm{M/H}]\simeq-0.8$ supports its classification as an in-situ bulge cluster and adds a new anchor to the in-situ age-metallicity relation.
  • The survey will provide homogeneous ages for 34 previously unstudied clusters, enabling systematic tests of cluster origin by combining age, metallicity, and orbital information.
  • The two age determinations demonstrate that the CARMA fitting method works in both optical and near-infrared passbands, so it can be applied to the full MGCS sample including heavily extincted bulge clusters.

Reading between the lines

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

  • If follow-up spectroscopy confirms 2MASS-GC01 as an open cluster, the Galactic cluster census would lose a claimed globular, and the boundary between old open clusters and young globulars would need to be redrawn, with consequences for models of massive cluster formation in the thin disc.
  • The successful near-infrared fit for 2MASS-GC01 suggests that age determinations for the other six heavily reddened MGCS bulge targets may be feasible despite extreme extinction, though residual differential reddening will likely dominate their uncertainties.
  • A young, massive, metal-poor cluster like 2MASS-GC01, if real, challenges scenarios in which massive clusters form only at early times or in gas-rich mergers, since the thin disc would have had to produce a compact $10^5\,M_\odot$ cluster just 7 Gyr ago.
  • The paper's comparison with the disc star-formation history hints that cluster formation in the thin disc continued until a relatively late epoch, a claim that could be tested with more young, disc-borne clusters from the MGCS sample.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

2 major / 5 minor

Summary. The paper introduces the Hubble Missing Globular Cluster Survey (MGCS), a Treasury program targeting 34 kinematically confirmed Milky Way globular clusters that lack previous HST imaging, and presents first results for two clusters. Using deep HST photometry (ACS/WFC F606W,F814W for ESO452-11; WFC3/IR F125W,F160W for 2MASS-GC01) and the CARMA Bayesian isochrone-fitting framework with BaSTI models, the authors derive an age of 13.59 (+0.48/−0.69) Gyr at [M/H]=−0.80 for ESO452-11, and an age of 7.22 (+0.93/−1.11) Gyr at [M/H]=−0.73 for 2MASS-GC01. They use the results to argue that ESO452-11 is an old in-situ cluster, while 2MASS-GC01 is either the youngest known Galactic globular cluster or a massive, compact open cluster, based also on its circular, thin-disc orbit and structural parameters.

Significance. The MGCS itself is a valuable legacy program that fills a real observational gap, and the homogeneous CARMA age-analysis framework is well suited to its goals. The ESO452-11 age is convincing: the two independent fits in the (mF606W−mF814W, mF606W) and (mF606W−mF814W, mF814W) planes agree within the quoted uncertainties, and the resulting age, metallicity, distance, and reddening are consistent with earlier partial constraints. This result alone validates the survey's approach. The 2MASS-GC01 result is more speculative because the two fits differ by ~1.8 Gyr and the paper explicitly acknowledges severe residual differential reddening; the headline nature claim therefore rests on an under-characterized systematic. If the young age is confirmed, this would be an important constraint on cluster formation in the thick/thin disc, but the current manuscript does not yet provide the needed demonstration that the age is robust against residual reddening.

major comments (2)
  1. [§3.2, Fig. 6] The two independent fits for 2MASS-GC01 return ages of 6.32 (+0.25/−0.21) and 8.12 (+0.13/−0.10) Gyr, which are mutually inconsistent by far more than their formal errors. The text states in §3.2 that 'despite the differential reddening correction, the photometry still suffers from severe residual differential reddening.' The adopted combined age, t=7.22 (+0.93/−1.11) Gyr, is an envelope spanning the two runs rather than a statistically meaningful combination, and no analysis demonstrates that residual reddening does not bias the turn-off and subgiant morphology that carries the age information. Because the central claim that 2MASS-GC01 is either the youngest known globular cluster or a massive open cluster depends on this young age, the authors should either incorporate a residual-reddening term into the MCMC likelihood, or otherwise demonstrate that the age inference is insensitive to the residual extinction (e.g., by fitting only stars in the least reddened subregions, or by comparing to an independent optical/NIR dataset), before drawing the headline conclusion.
  2. [§3.2 (footnote 7) and §3.3] The [Fe/H] value used for 2MASS-GC01 in the age-metallicity plane and in the metallicity-gradient comparison assumes the same [α/Fe] as ESO452-11, with no spectroscopic support. As the footnote acknowledges, a ±0.15 uncertainty in [α/Fe] translates to ±0.11 dex in [Fe/H]. The claim in §3.3 that 2MASS-GC01 is '> 0.5 dex more metal poor than open clusters at similar Galactocentric distances' is sensitive to this assumption. Please quantify how the conclusion changes over a plausible [α/Fe] range (e.g., 0.0 to +0.4) for a disc-born cluster, or soften the metallicity-outlier argument until spectroscopy constrains [α/Fe].
minor comments (5)
  1. [Fig. 6 caption] The label '2MS-GC01sel' should read '2MASS-GC01 selected'.
  2. [§4 vs. §3.2] The age of NGC 288 is attributed to Ceccarelli et al. (2025) in the conclusions, while §3.2 attributes the same measurement to Aguado-Agelet et al. (2025); please harmonize these citations.
  3. [§3.1] The inference that the low-mass population of ESO452-11 has been depleted by internal relaxation relies on a completeness estimate from NGC 2298 rather than on artificial-star tests for the MGCS data; a direct completeness simulation would strengthen this interpretation.
  4. [Acknowledgements] The word 'aknowledges' should be spelled 'acknowledges'.
  5. [§2] The phrase 'the publicly available library HST ePSFs' is missing a preposition; it should read 'the publicly available library of HST ePSFs'.

Circularity Check

0 steps flagged · score 1.0 of 10

No significant circularity: the age estimates for ESO452-11 and 2MASS-GC01 are derived from new HST photometry fitted to external BaSTI isochrones; CARMA self-citations supply methodology and homogeneous comparison, not the target ages.

full rationale

The reported ages are produced by fitting deep, newly obtained HST photometry to a fine grid of solar-scaled BaSTI stellar models within a Bayesian MCMC isochrone-fitting framework. The model grid is external (Hidalgo et al. 2018; Pietrinferni et al. 2021), the photometry is new, and the fitted outputs (age, metallicity, distance, reddening) are jointly constrained by the observed CMD morphology, including several magnitudes below the main-sequence turn-off. The self-citations to the CARMA project (Massari et al. 2023) describe the fitting machinery and the homogeneous comparison sample; they do not inject the target ages, and no parameter fitted to the target clusters is renamed as a prediction. The assumption of the same [alpha/Fe] ratio for 2MASS-GC01 as for ESO452-11 is an explicit assumption used only for the [M/H]-to-[Fe/H] conversion, not for the age determination itself. The acknowledged severe residual differential reddening in 2MASS-GC01 is a stated robustness limitation, not a circular construction. No uniqueness theorem is invoked, and no known result is merely renamed.

Assumptions & free parameters 12 free parameters · 6 assumptions · 0 invented entities

The central age estimates rest on the BaSTI evolutionary models, the assumed extinction law, and the differential reddening correction, in addition to the fitted parameters. The [alpha/Fe] assumption for 2MASS-GC01 is a notable prior not grounded in direct measurement.

free parameters (12)
  • Age of ESO452-11 = 13.59 Gyr (+0.48/-0.69)
    Derived from isochrone fitting to the CMD; the central result of the paper.
  • [M/H] of ESO452-11 = -0.80 (+0.08/-0.11)
    Fitted in the same Bayesian isochrone fit.
  • E(B-V) of ESO452-11 = 0.54 +/- 0.01
    Fitted reddening, consistent with prior literature.
  • Distance modulus of ESO452-11 = 14.29 +/- 0.03
    Fitted distance modulus, corresponding to a distance of 7.2 kpc.
  • Age of 2MASS-GC01 = 7.22 Gyr (+0.93/-1.11)
    Combined solution from two CMD fits; central result.
  • [M/H] of 2MASS-GC01 = -0.73 (+0.06/-0.06)
    Fitted in the same analysis.
  • E(B-V) of 2MASS-GC01 = 7.27 (+0.02/-0.03)
    Extreme reddening, the largest known for a Milky Way cluster.
  • Distance modulus of 2MASS-GC01 = 12.36 (+0.03/-0.02)
    Fitted distance modulus, corresponding to a distance of 2.96 kpc.
  • Assumed [alpha/Fe] for 2MASS-GC01 = 0.20 (assumed, same as ESO452-11), with +/- 0.15 uncertainty
    No spectroscopic alpha-abundance measurement exists; the same value as ESO452-11 is assumed, contributing +/- 0.11 dex to [Fe/H] uncertainty.
  • Reddening law R_V = 3.1 (assumed)
    Cardelli et al. (1989) law with R_V=3.1 is assumed for extinction corrections; at E(B-V)~7 this choice affects transformed magnitudes.
  • Prior widths for ESO452-11 isochrone fit = sigma[M/H]=0.1; sigma[E(B-V)]=0.05; sigma[DM]=0.10
    Chosen by hand as loose priors (Table 1); they affect the posterior but are not derived from the data.
  • Prior widths for 2MASS-GC01 isochrone fit = sigma[M/H]=0.1; sigma[E(B-V)]=0.20; sigma[DM]=0.10
    Chosen by hand as loose priors (Table 1); the wider reddening prior reflects the extreme extinction.
assumptions (6)
  • domain assumption BaSTI stellar evolution models are accurate representations of stellar structure and atmospheres
    The age and metallicity are derived by fitting these models (Hidalgo et al. 2018, Pietrinferni et al. 2021) to the observed CMDs; errors in model physics translate directly into systematic age errors.
  • domain assumption Solar-scaled models with global metallicity [M/H] are equivalent to alpha-enhanced models at the same [M/H] for these bands
    Invoked in Sect. 3.2 via Salaris et al. (1993) and Cassisi et al. (2004); the relation [M/H]=[Fe/H]+log(0.694*10^([alpha/Fe])+0.301) is assumed.
  • domain assumption The Cardelli et al. (1989) extinction law with R_V=3.1 applies along these heavily reddened lines of sight
    Used to correct magnitudes for extinction; for 2MASS-GC01 with E(B-V)=7.27, a non-standard R_V could alter the derived distance and age.
  • domain assumption Differential reddening is fully corrected by the Milone et al. (2012) method
    Adopted for both clusters; the paper states residual differential reddening remains for 2MASS-GC01, partially invalidating this assumption.
  • domain assumption Each cluster is a simple stellar population in the fitted region
    The fit assumes a single age and metallicity; the paper notes multiple populations can split sequences below the MSTO in IR bands, but judges it not to affect age estimates.
  • domain assumption Membership and kinematic confirmation of the clusters from prior catalogs is correct
    Cluster membership is based on prior proper motion and radial velocity catalogs (Vasiliev and Baumgardt 2021, Baumgardt and Vasiliev 2021, Pace et al. 2023), which the survey adopts.

how reviews work

0 comments
Cite this review

Pith. "Pith review of The $Hubble$ Missing Globular Cluster Survey. I. Survey overview and the first precise age estimate for ESO452-11 and 2MASS-GC01." pith.science (2026). https://pith.science/paper/GJKF5KPR

@misc{pith2026250201741,
  author       = {Pith},
  title        = {Pith review of: The $Hubble$ Missing Globular Cluster Survey. I. Survey overview and the first precise age estimate for ESO452-11 and 2MASS-GC01},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/GJKF5KPR}},
  note         = {Machine review of arXiv:2502.01741}
}
abstract

We present the $Hubble$ Missing Globular Cluster Survey (MGCS), a $Hubble$ $Space$ $Telescope$ Treasury Program dedicated to the observation of all kinematically confirmed Milky Way globular clusters that missed previous $Hubble$ imaging. After introducing the aims of the programme and describing its target clusters, we showcase the first results of the survey. These are related to two clusters, one located at the edge of the Milky Way bulge and observed in optical bands, namely ESO452-11, and one located in the Galactic disc observed in the near-IR, namely 2MASS-GC01. For both clusters, the deep colour-magnitude diagrams obtained from the MGCS observations reach several magnitudes below their main-sequence turn-off and thus enable the first precise estimate of their age. By using the methods developed in the Cluster Ages to Reconstruct the Milky Way Assembly (CARMA) project, we find ESO452-11 to be an old metal-intermediate globular cluster, with ${\rm [M/H]}\simeq-0.80^{+0.08}_{-0.11}$ and an age of ${\rm t}=13.59^{+0.48}_{-0.69}$ Gyr. Its location on the age-metallicity relation makes it consistent with an in situ origin, in agreement with its dynamical properties. On the other hand, the results for 2MASS-GC01 highlight it as a young metal-intermediate cluster, with an age of ${\rm t}=7.22^{+0.93}_{-1.11}$ Gyr at ${\rm [M/H]}=-0.73^{+0.06}_{-0.06}$. Despite the large associated uncertainty, our age estimate for this extremely extincted cluster indicates it to be either the youngest globular cluster known to date or a massive and compact open cluster, which is consistent with its almost circular, disc-like orbit

Figures

Figures reproduced from arXiv: 2502.01741 by the authors.

Figure 1
Figure 1. Distribution of the targets of MGCS (labelled and high [PITH_FULL_IMAGE:figures/full_fig_p003_1.png] view at source ↗
Figure 2
Figure 2. Overview CMDs (not corrected for differential reddening) for ESO452-11 and 2MASS-GC01. Left and middle panels: CMDs of ESO452-11 considering all stars in the central ACS/WFC and parallel WFC3/UVIS fields, respectively. Right panel: CMD of 2MASS-GC01 based on WFC3/IR data. The dashed grey lines mark the saturation threshold. the differential-reddening corrected CMD, and used this to se￾lect the sample of stars to fit… view at source ↗
Figure 3
Figure 3. Differential reddening maps for ESO452-11 (left panel) and 2MASS-GC01 (right panel). Please note the very different amplitude of the ∆E(B − V) scale in the two panels. The centre of the clusters as quoted in Harris (1996, 2010 edition) is shown as a blue cross. Prior parameter ESO452-11 2MASS-GC01 [M/H] -0.9 -0.7 σM/H 0.1 0.1 E(B-V) 0.55 6.8 σE(B−V) 0.05 0.20 DM0 14.40 12.50 σDM0 0.10 0.10 [PITH_FULL_IMAGE:figures/… view at source ↗
Figures from the paper (3 more)
Figure 4
Figure 4. Figure 4: Results of the isochrone fitting for ESO452-11. Panels a) and b) show the (mF606W − mF814W, mF606W) and the (mF606W − mF814W, mF814W) CMDs, respectively. The grey symbols describe the whole sample of stars in the cluster catalogue, while green symbols show the stars ef…
Figure 5
Figure 5. Figure 5: Location in the energy-vertical angular momentum space [PITH_FULL_IMAGE:figures/full_fig_p008_5.png]
Figure 6
Figure 6. Figure 6: Results of the isochrone fitting for 2MASS-GC01. By adopting the tools and the methods developed within the CARMA project (Massari et al. 2023), we find ESO452-11 to be a 13.59+0.48 −0.69-Gyr-old GC at an intermediate metallicity of [M/H] = −0.80. These values make ESO…

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

112 extracted references · 54 canonical work pages

  1. [1]

    2025, submitted, arXiv:2502.20436

    Aguado-Agelet , F., Massari , D., Monelli , M., et al. 2025, submitted, arXiv:2502.20436

    arXiv 2025

  2. [2]

    2024, , 687, A101

    Alvarez-Baena , N., Carrera , R., Thompson , H., et al. 2024, , 687, A101

    2024

  3. [3]

    A., Fanelli , C., Origlia , L., et al

    Alvarez Garay , D. A., Fanelli , C., Origlia , L., et al. 2024, , 686, A198

    2024

  4. [4]

    2016, Empirical Models for the WFC3/IR PSF , Space Telescope WFC Instrument Science Report

    Anderson , J. 2016, Empirical Models for the WFC3/IR PSF , Space Telescope WFC Instrument Science Report

    2016

  5. [5]

    & King , I

    Anderson , J. & King , I. R. 2006, PSFs, Photometry, and Astronomy for the ACS/WFC , Instrument Science Report ACS 2006-01

    2006

  6. [6]

    & Ryon , J

    Anderson , J. & Ryon , J. E. 2018, Improving the Pixel-Based CTE-correction Model for ACS/WFC , Instrument Science Report ACS 2018-04, 37 pages

    2018

  7. [7]

    R., & Meyer , M

    Bastian , N., Covey , K. R., & Meyer , M. R. 2010, , 48, 339

    2010

  8. [8]

    & Hilker , M

    Baumgardt , H. & Hilker , M. 2018, , 478, 1520

    2018

Show all 112 references
  1. [9]

    2020, , 37, e046

    Baumgardt , H., Sollima , A., & Hilker , M. 2020, , 37, e046

    2020

  2. [10]

    & Vasiliev , E

    Baumgardt , H. & Vasiliev , E. 2021, , 505, 5957

    2021

  3. [11]

    R., Piotto , G., Anderson , J., et al

    Bedin , L. R., Piotto , G., Anderson , J., et al. 2004, , 605, L125

    2004

  4. [12]

    R., Salaris , M., Anderson , J., et al

    Bedin , L. R., Salaris , M., Anderson , J., et al. 2023, , 518, 3722

    2023

  5. [13]

    Bellini , A., Anderson , J., & Bedin , L. R. 2011, , 123, 622

    2011

  6. [14]

    R., et al

    Bellini , A., Anderson , J., Bedin , L. R., et al. 2017, , 842, 6

    2017

  7. [15]

    & Bedin , L

    Bellini , A. & Bedin , L. R. 2009, , 121, 1419

    2009

  8. [16]

    P., et al

    Bellini , A., Piotto , G., Milone , A. P., et al. 2013, , 765, 32

    2013

  9. [17]

    W., Koposov , S

    Belokurov , V., Erkal , D., Evans , N. W., Koposov , S. E., & Deason , A. J. 2018, , 478, 611

    2018

  10. [18]

    & Kravtsov , A

    Belokurov , V. & Kravtsov , A. 2024, , 528, 3198

    2024

  11. [19]

    1999, , 136, 363

    Bica , E., Ortolani , S., & Barbuy , B. 1999, , 136, 363

    1999

  12. [20]

    Bica , E., Ortolani , S., Barbuy , B., & Oliveira , R. A. P. 2024, , 687, A201

    2024

  13. [21]

    & Bica , E

    Bonatto , C. & Bica , E. 2008, , 479, 741

    2008

  14. [22]

    M., Cassisi , S., D'Antona , F., et al

    Brown , T. M., Cassisi , S., D'Antona , F., et al. 2016, , 822, 44

    2016

  15. [23]

    J., et al

    Cadelano , M., Dalessandro , E., Webb , J. J., et al. 2020, , 499, 2390

    2020

  16. [24]

    M., Cautun , M., Deason , A

    Callingham , T. M., Cautun , M., Deason , A. J., et al. 2022, , 513, 4107

    2022

  17. [25]

    A., Clayton , G

    Cardelli , J. A., Clayton , G. C., & Mathis , J. S. 1989, , 345, 245

    1989

  18. [26]

    & Bragaglia , A

    Carretta , E. & Bragaglia , A. 2023, , 677, A73

    2023

  19. [27]

    2004, , 616, 498

    Cassisi , S., Salaris , M., Castelli , F., & Pietrinferni , A. 2004, , 616, 498

    2004

  20. [28]

    2025, submitted, arXiv:2503.02939

    Ceccarelli , E., Massari , D., Aguado-Agelet , F., et al. 2025, submitted, arXiv:2503.02939

    2025 arXiv

  21. [29]

    2024 a , , 684, A37

    Ceccarelli , E., Massari , D., Mucciarelli , A., et al. 2024 a , , 684, A37

    2024

  22. [30]

    2024 b , , 691, A226

    Ceccarelli , E., Mucciarelli , A., Massari , D., Bellazzini , M., & Matsuno , T. 2024 b , , 691, A226

    2024

  23. [31]

    1995, , 444, L9

    Chaboyer , B. 1995, , 444, L9

    1995

  24. [32]

    & Gnedin , O

    Chen , Y. & Gnedin , O. Y. 2024, The Open Journal of Astrophysics, 7, 23

    2024

  25. [33]

    P., Marino , A

    Cordoni , G., Milone , A. P., Marino , A. F., et al. 2023, , 672, A29

    2023

  26. [34]

    Cornish , A. S. M., Phelps , R. L., Briley , M. M., & Friel , E. D. 2006, , 131, 2543

    2006

  27. [35]

    R., et al

    Crociati , C., Valenti , E., Ferraro , F. R., et al. 2023, , 951, 17

    2023

  28. [36]

    2022, , 940, 170

    Dalessandro , E., Crociati , C., Cignoni , M., et al. 2022, , 940, 170

    2022

  29. [37]

    2010, , 718, 105

    De Marchi , G., Paresce , F., & Portegies Zwart , S. 2010, , 718, 105

    2010

  30. [38]

    P., et al

    del Pino , A., Libralato , M., van der Marel , R. P., et al. 2022, , 933, 76

    2022

  31. [39]

    2010, , 708, 698

    Dotter , A., Sarajedini , A., Anderson , J., et al. 2010, , 708, 698

    2010

  32. [40]

    Fall , S. M. & Rees , M. J. 1985, , 298, 18

    1985

  33. [41]

    M., et al

    Fanelli , C., Origlia , L., Rich , R. M., et al. 2024, , 690, A139

    2024

  34. [42]

    R., Dalessandro , E., Mucciarelli , A., et al

    Ferraro , F. R., Dalessandro , E., Mucciarelli , A., et al. 2009, , 462, 483

    2009

  35. [43]

    R., Lanzoni , B., Dalessandro , E., et al

    Ferraro , F. R., Lanzoni , B., Dalessandro , E., et al. 2012, , 492, 393

    2012

  36. [44]

    R., Massari , D., Dalessandro , E., et al

    Ferraro , F. R., Massari , D., Dalessandro , E., et al. 2016, , 828, 75

    2016

  37. [45]

    R., Pallanca , C., Lanzoni , B., et al

    Ferraro , F. R., Pallanca , C., Lanzoni , B., et al. 2021, Nature Astronomy, 5, 311

    2021

  38. [46]

    Forbes , D. A. 2020, , 493, 847

    2020

  39. [47]

    Forbes , D. A. & Bridges , T. 2010, , 404, 1203

    2010

  40. [48]

    2013, Publications of the Astronomical Society of the Pacific, 125, 306

    Foreman-Mackey, D., Hogg, D., Lang, D., & Goodman, J. 2013, Publications of the Astronomical Society of the Pacific, 125, 306

    2013

  41. [49]

    Gaia Collaboration , Prusti , T., de Bruijne , J. H. J., et al. 2016, , 595, A1

    2016

  42. [50]

    Gaia Collaboration , Vallenari , A., Brown , A. G. A., et al. 2023, , 674, A1

    2023

  43. [51]

    R., Fern \'a ndez-Trincado , J

    Garro , E. R., Fern \'a ndez-Trincado , J. G., Minniti , D., et al. 2023, , 669, A136

    2023

  44. [52]

    R., Minniti , D., & Fern \'a ndez-Trincado , J

    Garro , E. R., Minniti , D., & Fern \'a ndez-Trincado , J. G. 2024, , 687, A214

    2024

  45. [53]

    2008, , 120, 583

    Girardi , L., Dalcanton , J., Williams , B., et al. 2008, , 120, 583

    2008

  46. [54]

    2004, , 42, 385

    Gratton , R., Sneden , C., & Carretta , E. 2004, , 42, 385

    2004

  47. [55]

    2021, , 503, 1490

    H \"a berle , M., Libralato , M., Bellini , A., et al. 2021, , 503, 1490

    2021

  48. [56]

    Harris , W. E. 1996, , 112, 1487

    1996

  49. [57]

    H., et al

    Helmi , A., Babusiaux , C., Koppelman , H. H., et al. 2018, , 563, 85

    2018

  50. [58]

    2019, , 483, 1400

    H \'e nault-Brunet , V., Gieles , M., Sollima , A., et al. 2019, , 483, 1400

    2019

  51. [59]

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

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

    2018

  52. [60]

    P., Mackereth , J

    Horta , D., Schiavon , R. P., Mackereth , J. T., et al. 2020, , 493, 3363

    2020

  53. [61]

    Hunt , E. L. & Reffert , S. 2024, , 686, A42

    2024

  54. [62]

    L., Jarrett , T

    Hurt , R. L., Jarrett , T. H., Kirkpatrick , J. D., et al. 2000, , 120, 1876

    2000

  55. [63]

    Ivanov , V. D. & Borissova , J. 2002, , 390, 937

    2002

  56. [64]

    E., Klos , J

    Just , A., Piskunov , A. E., Klos , J. H., Kovaleva , D. A., & Polyachenko , E. V. 2023, , 672, A187

    2023

  57. [65]

    Kinman , T. D. 1959, , 119, 538

    1959

  58. [66]

    J., & Kunder , A

    Koch , A., Hansen , C. J., & Kunder , A. 2017, , 604, A41

    2017

  59. [67]

    Koposov , S., de Jong , J. T. A., Belokurov , V., et al. 2007, , 669, 337

    2007

  60. [68]

    Kruijssen , J. M. D., Pfeffer , J. L., Reina-Campos , M., Crain , R. A., & Bastian , N. 2019, , 486, 3180

    2019

  61. [69]

    B., Schuster , H

    Lauberts , A., Holmberg , E. B., Schuster , H. E., & West , R. M. 1981, , 43, 307

    1981

  62. [70]

    A., & Mendel , J

    Leaman , R., VandenBerg , D. A., & Mendel , J. T. 2013, , 436, 122

    2013

  63. [71]

    P., et al

    Libralato , M., Bellini , A., van der Marel , R. P., et al. 2023, , 950, 101

    2023

  64. [72]

    2022, , 934, 150

    Libralato , M., Bellini , A., Vesperini , E., et al. 2022, , 934, 150

    2022

  65. [73]

    2023, , 669, A119

    Magrini , L., Viscasillas V \'a zquez , C., Spina , L., et al. 2023, , 669, A119

    2023

  66. [74]

    A., Sharma , S., et al

    Malhan , K., Ibata , R. A., Sharma , S., et al. 2022, , 926, 107

    2022

  67. [75]

    2009, , 694, 1498

    Mar \' n-Franch , A., Aparicio , A., Piotto , G., et al. 2009, , 694, 1498

    2009

  68. [76]

    2023, , 680, A20

    Massari , D., Aguado-Agelet , F., Monelli , M., et al. 2023, , 680, A20

    2023

  69. [77]

    A., Helmi , A., et al

    Massari , D., Breddels , M. A., Helmi , A., et al. 2018, Nature Astronomy, 2, 156

    2018

  70. [78]

    2020, , 633, A36

    Massari , D., Helmi , A., Mucciarelli , A., et al. 2020, , 633, A36

    2020

  71. [79]

    H., & Helmi , A

    Massari , D., Koppelman , H. H., & Helmi , A. 2019, , 630, L4

    2019

  72. [80]

    R., et al

    Massari , D., Mucciarelli , A., Ferraro , F. R., et al. 2014, , 795, 22

    2014

  73. [81]

    2017, , 598, L9

    Massari , D., Posti , L., Helmi , A., Fiorentino , G., & Tolstoy , E. 2017, , 598, L9

    2017

  74. [82]

    McMillan , P. J. 2017, , 465, 76

    2017

  75. [83]

    Milone , A. P. & Marino , A. F. 2022, Universe, 8, 359

    2022

  76. [84]

    P., Piotto , G., Bedin , L

    Milone , A. P., Piotto , G., Bedin , L. R., et al. 2012, , 540, A16

    2012

  77. [85]

    P., Piotto , G., Renzini , A., et al

    Milone , A. P., Piotto , G., Renzini , A., et al. 2017, , 464, 3636

    2017

  78. [86]

    W., & Rieke , M

    Minniti , D., Olszewski , E. W., & Rieke , M. 1995, , 110, 1686

    1995

  79. [87]

    2023, , 522, 4404

    Monty , S., Yong , D., Massari , D., et al. 2023, , 522, 4404

    2023

  80. [88]

    2018, , 481, 3382

    Nardiello , D., Libralato , M., Piotto , G., et al. 2018, , 481, 3382

    2018

  81. [89]

    M., et al

    Origlia , L., Massari , D., Rich , R. M., et al. 2013, , 779, L5

    2013

  82. [90]

    M., Ferraro , F

    Origlia , L., Rich , R. M., Ferraro , F. R., et al. 2011, , 726, L20

    2011

  83. [91]

    B., Koposov , S

    Pace , A. B., Koposov , S. E., Walker , M. G., et al. 2023, , 526, 1075

    2023

  84. [92]

    2024, , 690, A334

    Palla , M., Magrini , L., Spitoni , E., et al. 2024, , 690, A334

    2024

  85. [93]

    Paust , N. E. Q., Reid , I. N., Piotto , G., et al. 2010, , 139, 476

    2010

  86. [94]

    2021, , 908, 102

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

    2021

  87. [95]

    P., Bedin , L

    Piotto , G., Milone , A. P., Bedin , L. R., et al. 2015, , 149, 91

    2015

  88. [96]

    2018, , 620, A194

    Recio-Blanco , A. 2018, , 620, A194

    2018

  89. [97]

    2002, , 114, 375

    Salaris , M., Cassisi , S., & Weiss , A. 2002, , 114, 375

    2002

  90. [98]

    1993, , 414, 580

    Salaris , M., Chieffi , A., & Straniero , O. 1993, , 414, 580

    1993

  91. [99]

    R., Chaboyer , B., et al

    Sarajedini , A., Bedin , L. R., Chaboyer , B., et al. 2007, , 133, 1658

    2007

  92. [100]

    P., Phillips , S

    Schiavon , R. P., Phillips , S. G., Myers , N., et al. 2024, , 528, 1393

    2024

  93. [101]

    & Zinn , R

    Searle , L. & Zinn , R. 1978, , 225, 357

    1978

  94. [102]

    D., De Silva , G., Martell , S

    Simpson , J. D., De Silva , G., Martell , S. L., Navin , C. A., & Zucker , D. B. 2017, , 472, 2856

    2017

  95. [103]

    F., Cutri , R

    Skrutskie , M. F., Cutri , R. M., Stiening , R., et al. 2006, , 131, 1163

    2006

  96. [104]

    2022, , 512, 776

    Sollima , A., Gratton , R., Lucatello , S., & Carretta , E. 2022, , 512, 776

    2022

  97. [105]

    2022, , 659, A59

    Tarricq , Y., Soubiran , C., Casamiquela , L., et al. 2022, , 659, A59

    2022

  98. [106]

    F., Battaglia , G., Gran , F., et al

    Thomas , G. F., Battaglia , G., Gran , F., et al. 2024, , 690, A54

    2024

  99. [107]

    A., Brogaard , K., Leaman , R., & Casagrande , L

    VandenBerg , D. A., Brogaard , K., Leaman , R., & Casagrande , L. 2013, , 775, 134

    2013

  100. [108]

    & Baumgardt , H

    Vasiliev , E. & Baumgardt , H. 2021, , 505, 5978

    2021

  101. [109]

    J., Vesperini , E., Dalessandro , E., et al

    Webb , J. J., Vesperini , E., Dalessandro , E., et al. 2017, , 471, 3845

    2017

  102. [110]

    & Rix , H.-W

    Xiang , M. & Rix , H.-W. 2022, , 603, 599

    2022

  103. [111]

    , " * write output.state after.block = add.period write newline

    ENTRY address archiveprefix author booktitle chapter edition editor howpublished institution eprint journal key month note number organization pages publisher school series title type volume year label extra.label sort.label short.list INTEGERS output.state before.all mid.sent...

  104. [112]

    write newline

    " write newline "" before.all 'output.state := FUNCTION n.dashify 't := "" t empty not t #1 #1 substring "-" = t #1 #2 substring "--" = not "--" * t #2 global.max substring 't := t #1 #1 substring "-" = "-" * t #2 global.max substring 't := while if t #1 #1 substring * t #2 gl...

Pith tools

Reviewed August 9, 2026 · model on record in the stance chip above.