Pith. sign in

REVIEW 3 major objections 6 minor 2 cited by

Resolving the Metallicity Distribution of the Stellar Halo with the H3 Survey

T0 review · 3 major / 6 minor · reviewed 2026-08-14 · deepseek-v4-flash

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

Pith's one-line read This paper argues, from 4,232 kinematically selected halo giants in the H3 Survey, that the Milky Way's stellar halo has a mean metallicity of [Fe/H] ≈ -1.2 and no measurable gradient from 6 to 100 kpc, and that most of the halo resolves…

desk verdict The H3 halo metallicity measurement is a real step forward—simple unbiased selection, flat [Fe/H] ≈ −1.2 profile to 100 kpc, and honest caveats—though the kinematic-cut mock test can't catch orbital-metallicity bias, which is a minor caveat, not a fatal flaw. read the letter →

arxiv 1909.02007 v1 pith:SP23GNST submitted 2019-09-04 astro-ph.GA

Charlie Conroy , Rohan P. Naidu , Dennis Zaritsky , Ana Bonaca , Phillip Cargile , Benjamin D. Johnson , Nelson Caldwell This is my paper · ORCID
classification astro-ph.GA
keywords stellarhalometallicitydistributionH3SurveyGaiaGalacticarchaeologydwarfgalaxyaccretionchemicaltaggingMilkyWaystructure
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

The paper uses the H3 Survey's sample of 4,232 kinematically selected halo giants to establish the metallicity structure of the Milky Way's stellar halo out to 100 kpc. It claims that the halo has a mean metallicity of [Fe/H] ≈ -1.2 and a flat profile from 6 to 100 kpc, with no gradient, in contrast to earlier studies that found lower average metallicities and a decreasing trend. The paper attributes this difference to H3's unbiased target selection, which is based on magnitude and parallax rather than color or metallicity. It also shows that the halo is chemically and orbitally structured, not smooth: the Sagittarius stream, a radial-orbit merger remnant, a retrograde metal-poor component, and a disk-like 'in-situ' component confined to |z| < 10 kpc are all visible. If correct, the Milky Way's halo is metal-rich enough and massive enough to sit on the mass-metallicity relation defined by other galaxies, and the halo's assembly is dominated by the tidal disruption of dwarf galaxies.

What carries the argument

The central mechanism is H3's deliberately simple selection function: targets are chosen by apparent magnitude (r < 18), Gaia parallax (π < 0.5 mas), and high latitude, with no color or metallicity criterion, then restricted to giants (log g < 3.5) on halo-like orbits via |V − 200| > 180 km/s. Distances, metallicities, and [α/Fe] come from the MINESweeper pipeline. The paper argues that this selection is unbiased with radius, tests it against a smooth mock catalog, and then uses the z-component of angular momentum, Lz, to sort stars into prograde, radial, and retrograde orbit groups, revealing the discrete chemical-orbital populations.

What would settle it

A decisive test: in the same high-latitude fields, measure the median [Fe/H] of halo giants selected by the same kinematic and gravity cuts but with a deeper magnitude limit, say r < 19. The paper's claim predicts the same flat profile and a median of about −1.2 at all radii; a declining median with radius in the deeper sample would show that the H3 magnitude limit was imprinting the flat profile.

Watch

Extended reading notes

Core claim

The central claim is that previous estimates of the halo's metallicity were biased downward by color and metallicity preselection, and that a parallax- and magnitude-selected sample recovers the true distribution: a mean [Fe/H] ≈ -1.2 that is flat from the inner halo to 100 kpc. The paper further claims that this apparent uniformity is a superposition of discrete components with similar mean metallicities in the range -1.0 to -1.3: Gaia-Enceladus, the radial-orbit remnant, dominates to roughly 30 kpc; the Sagittarius stream dominates prograde orbits at 20 to 40 kpc; a retrograde metal-poor population extends to large radius; and a thick-disk-chemistry component confined to |z| < 10 kpc represents stars formed in the Galaxy, the 'in-situ' halo. On this view, most of the stellar halo by mass is accreted.

Load-bearing premise

The flat metallicity profile rests on the assumption that H3's magnitude and parallax selection, together with the kinematic and giant cuts, returns a metallicity distribution that is unbiased at every distance; the paper checks this only against a simulated smooth galaxy whose halo contains no substructure, and if real halo substructure interacts with the cuts, the flat profile could be partly a selection artifact.

Editorial extensions

If this is right

  • The canonical mean halo metallicity becomes [Fe/H] ≈ −1.2 rather than −1.6 to −1.7, so comparisons with other galaxies' halos shift accordingly.
  • The halo is resolved into discrete merger remnants; a smooth, single-component halo is ruled out at the mass scale probed by H3.
  • The flat metallicity profile follows from the similar mean metallicities of the dominant remnants, not from a smooth radial gradient; this makes the profile a by-product of assembly history.
  • The in-situ halo is a modest, disk-confined component: about 25% of the inner halo at 6–10 kpc and only a few percent beyond |z| ≈ 10 kpc.
  • With the revised halo mass and the new mean metallicity, the Milky Way halo is typical for its stellar mass, easing previous tension with the mass-metallicity relation.

Reading between the lines

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

  • Left implicit: if the flat profile is really the sum of components with nearly equal metallicities, then the profile should become more structured when the sample is split by orbital category, and that structure is already visible in the paper's Figures 5 and 8; extending this to separate [Fe/H] measurements per identified stream would directly test the coincidence.
  • A testable extension: because the survey's sensitivity to low-mass debris varies with distance, the full H3 sample should reveal more low-mass streams closer in; a quantitative completeness model would turn the current 'majority resolved' claim into a lower limit on the fraction of the halo in resolved substructure.
  • If the metal-poor retrograde component is a single ancient accretion event, its orbital poles should be tightly clustered; if it is several, the clustering should be loose. The full H3 sample can decide between these possibilities.
  • The mass-metallicity relation argument can be sharpened: measuring each remnant's mean [Fe/H] and estimating its progenitor stellar mass from its debris would test whether the redshift evolution of the relation, rather than progenitor mass alone, sets the similar metallicities.
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

3 major / 6 minor

Summary. The paper presents the metallicity distribution of 4,232 kinematically selected halo giants from the H3 Survey, a sample selected only by r<18 and parallax<0.5 mas. The central claims are that the stellar halo has a mean metallicity of [Fe/H] ≈ −1.2 with no discernible radial gradient from 6 to 100 kpc; that the halo is highly structured in orbital–chemical space, with identifiable contributions from the in-situ (thick-disk-chemistry) halo, Sagittarius, Gaia-Enceladus, and Sequoia; and that metal-poor stars with [Fe/H] < −2 are a small population at all radii. The paper further argues that the updated mean metallicity, combined with the Deason et al. (2019) halo mass estimate, places the Milky Way on the stellar mass–metallicity relation defined by other galaxies. The analysis relies on a mock-catalog test of the selection function (Section 3), comparisons to globular clusters and external spectroscopic surveys (Appendix A), and an explicit list of caveats (Section 5.1).

Significance. If the claims hold, the paper resolves long-standing discrepancies caused by metallicity-biased tracer selection and provides evidence that the stellar halo is predominantly built from accreted dwarf galaxies. The H3 selection function is a genuine advance, and the mock tests, cross-survey comparisons, and explicit caveats are commendable strengths. The claim that the Milky Way halo is typical for its mass is important for galaxy formation comparisons. However, as discussed below, the central metallicity claims rest on a kinematic selection whose bias is not directly tested, and the possible metallicity-scale offset is not fully propagated into the main conclusions.

major comments (3)
  1. [Section 3, Figure 1] The mock-catalog test validates the magnitude, parallax, and giant cuts against metallicity-dependent luminosity, but it cannot validate the kinematic cut |V−200| > 180 km/s. The R18/Galaxia halo has a smooth Gaussian MDF with no intrinsic correlation between metallicity and orbital properties, so the test is insensitive to a bias that arises when metallicity varies with orbital anisotropy. Since Figures 5 and 8 show exactly such correlations in the data (Sagittarius at prograde Lz, Gaia-Enceladus near Lz=0, and a metal-poor retrograde component), the possibility that the excluded low-peculiar-velocity or near-circular halo stars have a systematically different MDF is not addressed. Please either demonstrate with a mock that includes metallicity–kinematic correlations, or with a cosmological simulation, that the kinematic selection is unbiased, or explicitly restrict the headline claims to the kinematically selected population.
  2. [Section 5.1 and Appendix A] The possible 0.1–0.2 dex systematic offset in the metallicity scale is load-bearing for the headline value ⟨[Fe/H]⟩ = −1.2. Appendix A shows that H3 is about 0.2 dex more metal-rich than SEGUE for −2 < [Fe/H] < −1 and about 0.1 dex more metal-rich than LAMOST near [Fe/H] ≈ −1.2. The abstract and Figure 9 use −1.2, while Section 6 allows a value as low as −1.3. Because the mass–metallicity comparison shifts by the same amount, please propagate this systematic uncertainty into the mean metallicity and into the Figure 9 conclusion, and state the resulting allowed range for the Milky Way's position in that diagram.
  3. [Section 4.1 and Figure 4] The conclusion that the radial-orbit MDF is consistent with a single population, and the use of the two-parameter chemical evolution model to argue that one population dominates, is presented without statistical quantification. The model is fit to one radial bin and then replayed in other panels, which is illustrative, but the claim that 'one population dominates this radial range' should be supported by a formal goodness-of-fit or model comparison rather than visual inspection, especially because the same model is used elsewhere to argue against multi-component interpretations.
minor comments (6)
  1. [Section 2] The word 'reddenning' should be 'reddening'.
  2. [Section 5.4] The word 'empircally' should be 'empirically'.
  3. [Abstract and Section 4.1] The quoted value ⟨[Fe/H]⟩ = −1.2 is described as both a mean and a median at different points; please specify which statistic is used and use consistent notation.
  4. [Figure 3] The text notes 'marginal evidence' for a lower mean metallicity beyond 50 kpc; please provide the radial-bin statistics or a significance estimate for the gradient rather than relying only on visual inspection.
  5. [Figure 4] The chemical evolution model parameters p = 0.08 and M = 2.1 are quoted without uncertainties; please state whether these are fixed or fitted and report uncertainties if fitted.
  6. [Section 4.2] The definitions of the prograde, radial, and retrograde groupings are given numerically, but the choices are motivated by 'the distribution of stars in E−Lz space' in a paper in preparation; please describe the quantitative method used to set these boundaries in the present text.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: the headline metallicity and gradient are direct measurements validated against independent external benchmarks.

full rationale

The central result — a flat halo metallicity profile with mean [Fe/H] ≈ −1.2 — is obtained by applying a fixed kinematic cut (|V−200|>180 km/s) and a giant cut (log g<3.5) to H3 spectra and taking median metallicities; no parameter is fitted to the target quantity. Section 3's mock test is a legitimate forward validation: the R18/Galaxia catalog has known input metallicity profiles, the H3 selection is applied, and the recovered medians are compared to the true input values. The mock's smoothness limits the test's power with respect to orbit–metallicity correlations, but that is an external-validity caveat, not a circular reduction. The pipeline and survey are cited from same-author companion papers (Conroy et al. 2019; Cargile et al. 2019), but those papers validate MINESweeper against globular clusters and Appendix A compares H3 metallicities to independent APOGEE, LAMOST, and SEGUE data, so the self-citations are corroborated externally. Identifications of Sagittarius, Gaia-Enceladus, and Sequoia rest on prior independent literature and are used as classifications, not as derivations of the metallicity claims. The chemical-evolution-model curve is explicitly fit to one MDF panel and 'replicated ... for comparison purposes' (Fig. 7), so it is illustrative rather than a fitted prediction. In short, no load-bearing step equates an output to its input by construction.

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

The central claims rest on calibrated metallicity measurements, a mock-based selection test, and orbital calculations; no new physical entities are postulated. The free parameters relate to descriptive model fits or hand-chosen classification boundaries, not to the primary gradient and mean-metallicity results.

free parameters (4)
  • Chemical evolution model yield p = 0.08
    Fitted to the observed MDF in the 10-30 kpc radial bin (Section 4.1, Figure 4).
  • Chemical evolution model mass ratio M = 2.1
    Fitted to the observed MDF in the 10-30 kpc radial bin (Section 4.1, Figure 4).
  • Lz orbital grouping boundaries = -500 and 1000 km/s kpc
    Chosen by hand based on the distribution in E-Lz space (Section 4.2).
  • Sagittarius stream selection cut = Ly < -Lz - 3e3 km/s kpc
    Adopted to isolate Sagittarius stars in Ly-Lz space (Section 4.1, Figure 4), deferred to Johnson et al. in prep.
assumptions (4)
  • domain assumption MINESweeper-derived metallicities are accurate to approximately 0.1 dex
    The entire metallicity scale rests on this calibration, supported by globular cluster tests and cross-surveys (Appendix A), but the SEGUE comparison shows a possible 0.2 dex offset.
  • domain assumption The R18/Galaxia mock catalog is a reasonable representation of the Milky Way for testing selection biases
    Section 3 relies on this mock to argue that the selection function is unbiased; the mock's halo is smooth and Gaussian, which may not capture real substructure.
  • domain assumption Orbits and angular momenta are computed using the assumed LSR and Galactic potential from Schoenrich et al. (2010)
    Section 2 uses the local standard of rest from Schoenrich et al. (2010) and a Galactic potential to convert measured velocities into Lz and other orbital quantities.
  • domain assumption The known merger remnants (Gaia-Enceladus, Sagittarius, Sequoia) exist and are correctly identified as in the cited literature
    The decomposition into discrete remnants relies on previous published definitions and the paper does not independently derive their existence from a parameter-free model.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Resolving the Metallicity Distribution of the Stellar Halo with the H3 Survey." pith.science (2026). https://pith.science/paper/SP23GNST

@misc{pith2026190902007,
  author       = {Pith},
  title        = {Pith review of: Resolving the Metallicity Distribution of the Stellar Halo with the H3 Survey},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/SP23GNST}},
  note         = {Machine review of arXiv:1909.02007}
}
abstract

The Galactic stellar halo is predicted to have formed at least partially from the tidal disruption of accreted dwarf galaxies. This assembly history should be detectable in the orbital and chemical properties of stars. The H3 Survey is obtaining spectra for 200,000 stars, and, when combined with Gaia data, is providing detailed orbital and chemical properties of Galactic halo stars. Unlike previous surveys of the halo, the H3 target selection is based solely on magnitude and Gaia parallax; the survey therefore provides a nearly unbiased view of the entire stellar halo at high latitudes. In this paper we present the distribution of stellar metallicities as a function of Galactocentric distance and orbital properties for a sample of 4232 kinematically-selected halo giants to 100 kpc. The stellar halo is relatively metal-rich, [Fe/H]=-1.2, and there is no discernable metallicity gradient over the range $6<R_{\rm gal}<100$ kpc. However, the halo metallicity distribution is highly structured including distinct metal-rich and metal-poor components at $R_{\rm gal}<10$ kpc and $R_{\rm gal}>30$ kpc, respectively. Metal-poor stars with [Fe/H]$<-2$ are a small population of the halo at all distances and orbital categories. We associate the "in-situ" stellar halo with stars displaying thick-disk chemistry on halo-like orbits; such stars are confined to $|z|<10$ kpc. The majority of the stellar halo is resolved into discrete features in orbital-chemical space, suggesting that the bulk of the stellar halo formed from the accretion and tidal disruption of dwarf galaxies. (ABRIDGED)

Figures

Figures reproduced from arXiv: 1909.02007 by the authors.

Figure 1
Figure 1. Effect of the H3 selection function on the recovered metallicity profile in the halo. Top and bottom panels show two models for the input metallicity profile of the R18 mock stellar halo. Small points show the metal￾licities of kinematically-selected halo stars drawn from the R18 mock catalog subject to the H3 selection function (r < 18, π < 0.5) and the H3 window function. Large open symbols and errors show the med… view at source ↗
Figure 3
Figure 3. Stellar metallicity vs. distance from the Galactic plane (top panel) and Galactocentric radius (bottom panel) for kinematically-selected halo stars from the H3 Survey. Grey points have thick disk chemistry as defined in [PITH_FULL_IMAGE:figures/full_fig_p004_3.png] view at source ↗
Figure 4
Figure 4. in three radial bins. At Rgal < 10 kpc one clearly sees evidence for two distinct populations, including a main population with a mean metallicity of [Fe/H] = −1.2 and a secondary metal-rich population. Removing stars belonging to the in-situ halo as defined in [PITH_FULL_IMAGE:figures/full_fig_p004_4.png] view at source ↗
Figures from the paper (7 more)
Figure 4
Figure 4. Figure 4: Metallicity distribution functions (MDFs) in three radial bins for kinematically-selected halo giants. The grey dotted line is an analytic chemical evolution model fit to the distribution in the middle panel. In the left panel, we also show the MDF excluding the in-sit…
Figure 5
Figure 5. Figure 5: Top Panels: Metallicity vs. Galactocentric radius separated according to the z−component of the angular momentum (prograde, radial, and retrograde in the left, middle and right panels). Bottom panels: Distribution of stars in [α/Fe] vs. [Fe/H]. Only kinematically-selec…
Figure 6
Figure 6. Figure 6: As in [PITH_FULL_IMAGE:figures/full_fig_p006_6.png]
Figure 7
Figure 7. Figure 7: Metallicity distribution functions (MDFs) of H3 stars shown for prograde, radial, and retrograde orbits. Here we have removed the in-situ halo stars (those above the dashed lines in the lower panels of [PITH_FULL_IMAGE:figures/full_fig_p006_7.png]
Figure 4
Figure 4. Figure 4: Even after removing Sagittarius there are clearly at [PITH_FULL_IMAGE:figures/full_fig_p006_4.png]
Figure 8
Figure 8. Figure 8: Lz vs. [Fe/H] for kinematically-selected halo giants from the H3 Survey. Stars are grouped in three radial bins: Rgal < 10 kpc, 10 < Rgal < 30 kpc, and 30 < Rgal < 100 kpc. Grey points mark the in-situ halo stars defined in the bottom panels of [PITH_FULL_IMAGE:figure…
Figure 9
Figure 9. Figure 9: Total stellar halo mass vs. stellar halo metallicity. The metallicity is quoted at a common galactocentric distance of 30 kpc (although note that the MW gradient is flat so the choice of reference point will not change the location of the MW in this diagram). The MW me…

Discussion (0). Continue with ORCID to comment.

Forward citations

Cited by 2 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

  1. From metallicity distributions to mutual information: A new perspective on stellar halo assembly

    astro-ph.GA 2025-11 conditional novelty 6.0 of 10

    Mutual information between angular position and binary metallicity increases with radius in all five Aquarius stellar halos, and after satellite removal the residual signal is confined to the inner ~30-50 kpc.

  2. Elemental Abundances in M31: A Comparative Analysis of Iron and Alpha Element Abundances in the Outer Disk, Giant Stellar Stream, and Inner Halo of M31

    astro-ph.GA 2019-08 conditional novelty 6.0 of 10

    New Keck spectroscopy of 70 M31 red giants shows alpha-enhanced populations in the inner halo, Giant Stellar Stream, and outer disk, and suggests today's M31 satellites did not build the metal-rich inner halo.

Reference graph

Works this paper leans on

65 extracted references · 35 canonical work pages · cited by 2 Pith papers

  1. [1]

    G., Navarro, J

    Abadi, M. G., Navarro, J. F., & Steinmetz, M. 2006, MNRAS, 365, 747

    2006

  2. [2]

    F., Zucker, D

    Bell, E. F., Zucker, D. B., Belokurov, V ., et al. 2008, ApJ, 680, 295

    work page 2008

  3. [3]

    W., Koposov, S

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

    2018

  4. [4]

    & Gerhard, O

    Bland-Hawthorn, J. & Gerhard, O. 2016, Annual Review of Astronomy and Astrophysics, 54, 529

    work page 2016

  5. [5]

    F., & Kereš, D

    Bonaca, A., Conroy, C., Wetzel, A., Hopkins, P. F., & Kereš, D. 2017, ApJ, 845, 101

    2017

  6. [6]

    Bullock, J. S. & Johnston, K. V . 2005, ApJ, 635, 931

    2005

  7. [7]

    2019, arXiv e-prints, arXiv:1907.07690

    Dotter, A. 2019, arXiv e-prints, arXiv:1907.07690

    arXiv 2019

  8. [8]

    W., Latham, D

    Carney, B. W., Latham, D. W., Laird, J. B., & Aguilar, L. A. 1994, The Astronomical Journal, 107, 2240

    work page 1994

Show all 65 references
  1. [9]

    C., Chiba, M., et al

    Carollo, D., Beers, T. C., Chiba, M., et al. 2010, ApJ, 712, 692 12 CONROY ET AL

    2010

  2. [10]

    C., Lee, Y

    Carollo, D., Beers, T. C., Lee, Y . S., et al. 2007, Nature, 450, 1020

    2007

  3. [11]

    & Beers, T

    Chiba, M. & Beers, T. C. 2000, The Astronomical Journal, 119, 2843

    2000

  4. [12]

    2016, ApJ, 823, 102

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

    2016

  5. [13]

    Bellm, E., & Laher, R. R. 2017, ApJ, 849, 150

    2017

  6. [14]

    2019, arXiv e-prints, arXiv:1907.07684

    Conroy, C., Bonaca, A., Cargile, P., et al. 2019, arXiv e-prints, arXiv:1907.07684

    2019 arXiv

  7. [15]

    P., Cole, S., Frenk, C

    Cooper, A. P., Cole, S., Frenk, C. S., et al. 2010, MNRAS, 406, 744

    2010

  8. [16]

    P., Parry, O

    Cooper, A. P., Parry, O. H., Lowing, B., Cole, S., & Frenk, C. 2015, MNRAS, 454, 3185

    2015

  9. [17]

    & Binney, J

    Das, P. & Binney, J. 2016, MNRAS, 460, 1725

    2016

  10. [18]

    J., Belokurov, V ., & Sanders, J

    Deason, A. J., Belokurov, V ., & Sanders, J. L. 2019, arXiv e-prints, arXiv:1908.02763

    2019 arXiv

  11. [19]

    J., Mao, Y .-Y ., & Wechsler, R

    Deason, A. J., Mao, Y .-Y ., & Wechsler, R. H. 2016, ApJ, 821, 5 D’Souza, R. & Bell, E. F. 2018, MNRAS, 474, 5300

    2016

  12. [20]

    J., Lynden-Bell, D., & Sandage, A

    Eggen, O. J., Lynden-Bell, D., & Sandage, A. R. 1962, ApJ, 136, 748

    1962

  13. [21]

    2005, PASP, 117, 1411 Fernández-Alvar, E., Carigi, L., Allende Prieto, C., et al

    Fabricant, D., Fata, R., Roll, J., et al. 2005, PASP, 117, 1411 Fernández-Alvar, E., Carigi, L., Allende Prieto, C., et al. 2017, MNRAS, 465, 1586

    2005

  14. [22]

    S., McCarthy, I

    Font, A. S., McCarthy, I. G., Crain, R. A., Theuns, T., Schaye, J., Wiersma, R. P. C., & Dalla Vecchia, C. 2011, MNRAS, 416, 2802 Gaia Collaboration, Brown, A. G. A., Vallenari, A., Prusti, T., et al. 2018, A&A, 616, A1

    2011

  15. [23]

    F., et al

    Harmsen, B., Monachesi, A., Bell, E. F., et al. 2017, MNRAS, 466, 1491

    2017

  16. [24]

    Brown, A. G. A. 2018, Nature, 563, 85

    2018

  17. [25]

    A., Tian, H., & Sales, L

    Helmi, A., Veljanoski, J., Breddels, M. A., Tian, H., & Sales, L. V . 2017, A&A, 598, A58

    2017

  18. [26]

    & White, S

    Helmi, A. & White, S. D. M. 1999, MNRAS, 307, 495

    1999

  19. [27]

    Ibata, R., Irwin, M., Lewis, G., Ferguson, A. M. N., & Tanvir, N. 2001, Nature, 412, 49

    2001

  20. [28]

    A., Lewis, G

    Ibata, R. A., Lewis, G. F., & McConnachie, A. W. o. 2014, The Astrophysical Journal, 780, 128

    2014

  21. [29]

    & Belokurov, V

    Iorio, G. & Belokurov, V . 2019, MNRAS, 482, 3868 Ivezi´c, Ž., Sesar, B., Juri ´c, M., et al. 2008, ApJ, 684, 287

    2019

  22. [30]

    Leitner, S. N. 2008, ApJ, 689, 936

    2008

  23. [31]

    V ., Hernquist, L., & Bolte, M

    Johnston, K. V ., Hernquist, L., & Bolte, M. 1996, ApJ, 465, 278

    1996

  24. [32]

    2013, The Astrophysical Journal, 779, 102

    Gallazzi, A. 2013, The Astrophysical Journal, 779, 102

    2013

  25. [33]

    N., Lanfranchi, G

    Kirby, E. N., Lanfranchi, G. A., Simon, J. D., Cohen, J. G., & Guhathakurta, P. 2011, ApJ, 727, 78

    2011

  26. [34]

    Lancaster, L., Belokurov, V ., & Evans, N. W. 2019, MNRAS, 484, 2556

    2019

  27. [35]

    S., Beers, T

    Lee, Y . S., Beers, T. C., Sivarani, T., et al. 2008, AJ, 136, 2050

    2008

  28. [36]

    Licquia, T. C. & Newman, J. A. 2015, The Astrophysical Journal, 806, 96

    2015

  29. [37]

    J., et al

    Liu, S., Du, C., Newberg, H. J., et al. 2018, ApJ, 862, 163

    2018

  30. [38]

    1975, Vistas in Astronomy, 19, 299

    Lynden-Bell, D. 1975, Vistas in Astronomy, 19, 299

    1975

  31. [39]

    F., Faucher-Giguère, C.-A., Zolman, N., Muratov, A

    Ma, X., Hopkins, P. F., Faucher-Giguère, C.-A., Zolman, N., Muratov, A. L., Kereš, D., & Quataert, E. 2016, MNRAS, 456, 2140

    2016

  32. [40]

    T., Schiavon, R

    Mackereth, J. T., Schiavon, R. P., Pfeffer, J., et al. 2019, MNRAS, 482, 3426

    2019

  33. [41]

    Majewski, S. R. 1992, The Astrophysical Journal Supplement Series, 78, 87

    1992

  34. [42]

    R., Skrutskie, M

    Majewski, S. R., Skrutskie, M. F., Weinberg, M. D., & Ostheimer, J. C. 2003, ApJ, 599, 1082

    2003

  35. [43]

    2019, ApJ, 874, L35

    Matsuno, T., Aoki, W., & Suda, T. 2019, ApJ, 874, L35

    2019

  36. [44]

    A., Grand , R

    Monachesi, A., Gómez, F. A., Grand , R. J. J., et al. 2019, MNRAS, 485, 2589

    2019

  37. [45]

    2009, The Astrophysical Journal, 694, 130

    Duyne, J. 2009, The Astrophysical Journal, 694, 130

    2009

  38. [46]

    C., Vasiliev, E., Iorio, G., Evans, N

    Myeong, G. C., Vasiliev, E., Iorio, G., Evans, N. W., & Belokurov, V . 2019, MNRAS, 488, 1235

    2019

  39. [47]

    Nissen, P. E. & Schuster, W. J. 2010, A&A, 511, L10

    2010

  40. [48]

    W., Bullock, J

    Purcell, C. W., Bullock, J. S., & Kazantzidis, S. 2010, MNRAS, 404, 1711

    2010

  41. [49]

    Ryan, S. G. & Norris, J. E. 1991, AJ, 101, 1865

    1991

  42. [50]

    2018, PASP, 130, 074101 Schönrich, R., Binney, J., & Dehnen, W

    Andrae, R. 2018, PASP, 130, 074101 Schönrich, R., Binney, J., & Dehnen, W. 2010, MNRAS, 403, 1829

    2018

  43. [51]

    & Zinn, R

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

    1978

  44. [52]

    2011, ApJ, 731, 4

    Sesar, B., Juri´c, M., & Ivezi´c, Ž. 2011, ApJ, 731, 4

    2011

  45. [53]

    V ., & Binney, J

    Sharma, S., Bland-Hawthorn, J., Johnston, K. V ., & Binney, J. 2011, ApJ, 730, 3

    2011

  46. [54]

    P., Lee, Y

    Smolinski, J. P., Lee, Y . S., Beers, T. C., et al. 2011, AJ, 141, 89

    2011

  47. [55]

    & Zhen, C

    Sommer-Larsen, J. & Zhen, C. 1990, Monthly Notices of the Royal Astronomical Society, 242, 10

    1990

  48. [56]

    2011, PASP, 123, 1188

    Szentgyorgyi, A., Furesz, G., Cheimets, P., et al. 2011, PASP, 123, 1188

    2011

  49. [57]

    2019, ApJ, 879, 69

    Ting, Y .-S., Conroy, C., Rix, H.-W., & Cargile, P. 2019, ApJ, 879, 69

    2019

  50. [58]

    A., Irwin, M., Shetrone, M

    Venn, K. A., Irwin, M., Shetrone, M. D., Tout, C. A., Hill, V ., & Tolstoy, E. 2004, AJ, 128, 1177

    2004

  51. [59]

    2019, arXiv e-prints, arXiv:1908.09727

    Xiang, M., Ting, Y .-S., Rix, H.-W., Sand ford, N., Buder, S., Lind, K., Liu, X.-W., Shi, J.-R., & Zhang, H.-W. 2019, arXiv e-prints, arXiv:1908.09727

    2019 arXiv

  52. [60]

    2015, ApJ, 809, 144

    Xue, X.-X., Rix, H.-W., Ma, Z., Morrison, H., Bovy, J., Sesar, B., & Janesh, W. 2015, ApJ, 809, 144

    2015

  53. [61]

    J., et al

    Yanny, B., Rockosi, C., Newberg, H. J., et al. 2009, AJ, 137, 4377

    2009

  54. [62]

    Kurtz, M. J. 2013, ApJ, 771, L19

    2013

  55. [63]

    1993, in Astronomical Society of the Pacific Conference Series, V ol

    Zinn, R. 1993, in Astronomical Society of the Pacific Conference Series, V ol. 48, The Globular Cluster-Galaxy Connection, ed. G. H. Smith & J. P. Brodie, 38

    1993

  56. [64]

    M., et al

    Zolotov, A., Willman, B., Brooks, A. M., et al. 2009, ApJ, 702, 1058

    2009

  57. [65]

    J., Wu, Z., Ma, J., & Zhou, X

    Zuo, W., Du, C., Jing, Y ., Gu, J., Newberg, H. J., Wu, Z., Ma, J., & Zhou, X. 2017, ApJ, 841, 59

    2017

Pith tools

Reviewed August 14, 2026 · model on record in the stance chip above.