arxiv: 2604.02993 · v1 · submitted 2026-04-03 · 🌌 astro-ph.GA

Recognition: 2 theorem links

· Lean Theorem

Tracing the relic nature of compact galaxies through their globular cluster systems

Micheli T. Moura , Ana L. Chies-Santos , Cristina Furlanetto , Yingtian Chen , Oleg Y. Gnedin , Michael A. Beasley , Anna Ferr\'e-Mateu , Ling Zhu

show 1 more author

Juan Pablo Caso

Authors on Pith no claims yet

Pith reviewed 2026-05-13 18:06 UTC · model grok-4.3

classification 🌌 astro-ph.GA

keywords globular clusterscompact massive galaxiesrelic galaxiesgalaxy assemblytidal strippingin-situ formationex-situ accretionstellar populations

0 comments

The pith

Three compact massive galaxies match massive relic profiles through their globular cluster systems.

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

The paper applies a synthetic model of globular cluster formation to 17 compact massive galaxies drawn from the TNG100 simulation. The model assigns clusters to individual stellar particles based on age and local conditions, yielding origin, metallicity, and spatial data that can be compared directly to the galaxies' assembly histories. Three galaxies stand out with high fractions of in-situ clusters, narrow metallicity ranges, and compact distributions, consistent with systems that formed most of their stars early and experienced little subsequent growth. The analysis also shows that the mass fraction of globular clusters records the host's merger history more faithfully than the number fraction, and that the spatial extent of ex-situ clusters correlates tightly with the amount of stellar material stripped from the galaxy.

Core claim

Combining stellar assembly histories with globular cluster properties reveals that the mass fraction of clusters traces early accretion events more robustly than the number fraction. Three of the seventeen compact massive galaxies display the expected relic signatures: predominantly in-situ cluster formation, narrow metallicity distributions, and compact spatial profiles. A clear correlation emerges between the host galaxy's stripped stellar fraction and the radial extent of its ex-situ globular cluster population.

What carries the argument

The synthetic globular cluster formation model that assigns clusters to stellar particles according to age and local conditions, supplying origin, metallicity, and positional information for each cluster.

If this is right

Globular cluster mass fraction serves as a more reliable tracer of galaxy assembly history than number fraction.
Spatial profiles of ex-situ globular clusters can indicate the extent of tidal stripping experienced by the host galaxy.
The joint study of globular cluster populations and host stellar assembly provides a practical way to identify massive relic galaxies.
Early-formed clusters preserve assembly signals better than later-accreted ones.

Where Pith is reading between the lines

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

Surveys of globular cluster systems around nearby compact galaxies could be used to flag which ones are likely true relics with minimal late-time growth.
The same GC-based stripping diagnostic might be applied to galaxies in dense cluster environments to map their dynamical histories.
If the correlation between stripped fraction and ex-situ cluster extent holds in real data, it offers an observable route to quantify past tidal interactions without needing full merger trees.

Load-bearing premise

The synthetic model produces realistic positional, kinematic, and chemical properties for globular clusters that accurately reflect real galaxy assembly.

What would settle it

Comparison of the predicted in-situ fractions, metallicity widths, and spatial profiles for the three candidate relic galaxies against direct observations of massive compact galaxies known to have old stellar populations and little recent star formation.

Figures

Figures reproduced from arXiv: 2604.02993 by Ana L. Chies-Santos, Anna Ferr\'e-Mateu, Cristina Furlanetto, Juan Pablo Caso, Ling Zhu, Michael A. Beasley, Micheli T. Moura, Oleg Y. Gnedin, Yingtian Chen.

**Figure 1.** Figure 1: Stellar mass–size relation for the selected sample of CMGs at z = 0. A sample of TNG100 subhalos are shown as light gray circles for reference, while selected compact subhalos are represented by open circles. Dotted black line indicates the threshold of 2 kpc, while the dashed red line follows the surface density parameter for the selected sample (Re < 2 kpc, log Σ1.5 > 10.0 dex). 3. ANALYSIS 3.1. Assemb… view at source ↗

**Figure 2.** Figure 2: Stellar mass assembly histories of the compact massive host galaxies as a function of cosmic time. The stellar mass enclosed within the effective radius, Re,⋆, is normalized to its value at z = 0. Each host galaxy is shown in colored lines, where solid lines correspond to systems with satellite accretion fractions below 20%, while dashed lines indicate galaxies with more extended accretion histories (>… view at source ↗

**Figure 3.** Figure 3: GC in-situ fraction vs. host in-situ mass fraction. The diagonal dashed line indicates the 1:1 relation. The left panel shows the GC in-situ (Ngc) number fraction as a function of host in-situ mass fraction, the center panel shows the GC in-situ mass fraction as a function of host in-situ mass fraction, and the right panel shows the GC number vs. the GC mass fraction. We are considering just GCs with masse… view at source ↗

**Figure 4.** Figure 4: [Fe/H] distribution over ages for all GCs in each host galaxy. GCs in-situ are displayed in red, and ex-situ GCs are displayed in blue in all the frames. The horizontal gray indicates the [Fe/H]=−1, for reference. The most GC in-situ -dominated hosts are highlighted with ‘*’ symbol. The last row and column display the dispersion σ[Fe/H] for each host galaxy. The IDs 69530, 60753, 69512 are highlighted with… view at source ↗

**Figure 5.** Figure 5: Histograms of GC metallicity ([Fe/H]) for each host galaxy in the sample, showing the number of GCs (NGC) as a function of [Fe/H]. The distributions are color-coded in red and blue to represent in-situ and ex-situ populations, respectively. All the frames are ordered to follow the same sequence as in [PITH_FULL_IMAGE:figures/full_fig_p008_5.png] view at source ↗

**Figure 6.** Figure 6: The median metallicity ([Fe/H]) of the galaxies is plotted as a function of their in-situ GCs fraction. Each host galaxy is color-coded by its unique ID. cal signatures of early assembly and reflect the absence of significant late-time accretion [PITH_FULL_IMAGE:figures/full_fig_p009_6.png] view at source ↗

**Figure 7.** Figure 7: Stellar stripping fraction and the environment of each CMGs. Upper panel: Stellar stripping fraction of each host color-coded by r80 ex-situ/r80 in-situ. This ratio quantifies the relative spatial extension of ex-situ and in-situ GCs, where r80 denotes the radius enclosing 80% of the respective population. The host 69530 is shown in white, as it contains no ex-situ globular clusters. Lower panel: Stellar … view at source ↗

**Figure 8.** Figure 8: Combined cumulative distribution function (CDF) for all the hosts. In the first row, the components are color-coded by in-situ and ex-situ GCs in red (dashed) and blue (solid) lines, respectively. Second row shows the CDF color-coded by the r80 ex-situ/r80 in-situ ratio, where lower values represent small galactocentric distances for the ex-situ component. The third row shows the CDF color-coded by the st… view at source ↗

**Figure 9.** Figure 9: Relative galactocentric distance for in-situ and ex-situ component quantified by r80 ratio depending on host stellar stripping fraction. The gray dashed line indicates where both, in-situ and ex-situ population have comparable galactocentric extents. those near or below it indicate comparable or more compact ex-situ components. A trend is observed in which galaxies with higher stripping fractions tend to … view at source ↗

**Figure 10.** Figure 10: Histograms of GC colors (g − z) for each host galaxy in the sample, following the same scheme as in [PITH_FULL_IMAGE:figures/full_fig_p018_10.png] view at source ↗

**Figure 11.** Figure 11: g − z color distribution over ages for all GCs in each host galaxy. GCs in-situ are displayed in red, and ex-situ GCs are displayed in blue in all the frames. The Most GC in-situ -dominated hosts are highlighted with ‘*’ symbol. 19 [PITH_FULL_IMAGE:figures/full_fig_p019_11.png] view at source ↗

**Figure 12.** Figure 12: NGC and TN data from ACSVCS among the host sample from TNG100. Grey points represent individual ACSVCS galaxies. The black line shows the median for TN in bins of stellar mass, while the shaded region indicates the 16th–84th percentile range of the observed distribution on the right panel. The host CMGs (red points) lie within this observational range and follow the median relation, indicating that the nu… view at source ↗

read the original abstract

We investigate the synthetic model of globular cluster (GC) systems of 17 compact massive galaxies (CMGs) from the Illustris TNG100 simulation to explore their connection with massive relic galaxies, systems that have undergone little structural evolution across cosmic time. The co-evolution of the GC systems and their host galaxies is based on a GC formation and evolution model that assigns clusters to stellar particles according to age and local conditions, providing positional, kinematic, and chemical information for individual GCs. By combining stellar assembly histories, effective radius evolution, and GC properties such as in-situ vs. ex-situ origin, metallicity, and spatial distribution, we identify consistent signatures of early formation and late-time accretion. We find that the GC mass fraction traces the host assembly history more robustly than the GC number fraction, as massive clusters better preserve the imprint of the early accretion history. Three CMGs from TNG100 emerge as strong massive relic analogs, exhibiting high in-situ GC fractions, narrow metallicity distributions, and compact spatial distributions. A tight correlation between the host stripped fraction and the extent of the ex-situ GC population further reveals the possibility to consider GC spatial profiles as a signature to identify tidal stripping processes. These results indicate that the combined analysis of GC populations and host stellar assembly offers a robust diagnostic for identifying massive relic galaxies and constraining their evolutionary histories.

Editorial analysis

A structured set of objections, weighed in public.

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

Desk Editor's Note private letter to a colleague

Three TNG100 compact galaxies stand out as relic analogs from their GC properties, with a reported link between stripped fraction and ex-situ GC extent, but the whole thing rests on an unvalidated synthetic GC model.

read the letter

Three CMGs in the TNG100 run come out as strong massive relic candidates because their GC systems show high in-situ fractions, tight metallicity distributions, and stay compact. The paper also finds a clear link between the fraction of stripped stars and how extended the ex-situ GC population is, which could turn GC profiles into a practical way to spot past stripping. That is the concrete new piece: specific analogs plus a potential observable signature for tidal history. The simulation side is handled cleanly. They use an existing model that tags GCs to stellar particles based on age and local density, then track in-situ versus ex-situ origins along with metallicity and positions. This lets them tie GC statistics directly to the galaxies' merger and accretion histories. The point that mass fraction in GCs preserves the early assembly signal better than raw number counts is useful and follows from the way massive clusters form early. The main limitation is that none of this is checked against real GC systems in confirmed relics. We know a few local examples like NGC 1277, but the paper does not compare the synthetic metallicity spreads or radial profiles to those observed clusters. Without that step, it is hard to tell whether the reported signatures are genuine tracers or just how the model happens to behave in TNG100. The correlation with stripped fraction is internal to the run, so it could shift if the GC assignment rules change. This paper is aimed at researchers who already work with both simulations and GC observations in early-type galaxies. Someone looking for new ways to identify relics in upcoming surveys would find the proposed diagnostics worth testing. The thinking is straightforward and the methods are reproducible within the TNG framework. I would send it to peer review. The claims are specific enough that referees can ask for the missing observational comparisons, and the work gives a clear path forward even if the current evidence is simulation-only.

Referee Report

2 major / 2 minor

Summary. The paper analyzes synthetic globular cluster (GC) systems for 17 compact massive galaxies (CMGs) drawn from the Illustris TNG100 simulation. Using a model that assigns GCs to stellar particles based on age and local conditions, it combines stellar assembly histories, effective-radius evolution, and GC properties (in-situ/ex-situ origin, metallicity, spatial distribution) to identify three CMGs as strong massive-relic analogs characterized by high in-situ GC fractions, narrow metallicity distributions, and compact spatial profiles. It further reports a tight correlation between the host stripped fraction and the extent of the ex-situ GC population, proposing GC spatial profiles as a diagnostic for tidal-stripping processes.

Significance. If the synthetic GC model is shown to reproduce observed GC properties, the work supplies a simulation-based diagnostic that links GC observables to assembly history and could help identify relic galaxies in surveys. The finding that GC mass fraction traces early accretion more robustly than number fraction is a concrete, potentially testable insight.

major comments (2)

[§4] §4 (Results on relic identification): the claim that three specific CMGs are strong massive-relic analogs rests on the synthetic GC model producing realistic in-situ fractions, metallicity spreads, and radial profiles. The manuscript presents only internal TNG100 outputs and does not compare these quantities to observed GC systems in confirmed relics (e.g., NGC 1277, Mrk 1216), leaving open whether the reported signatures are robust or artifacts of the assignment rules.
[§3] §3 (GC formation and evolution model): the assignment of clusters to stellar particles according to age and local conditions is central to all downstream claims, yet no external validation against observed GC metallicity distributions or spatial profiles in compact galaxies is provided. Without such a test, the assertion that GC spatial profiles trace stripping processes cannot be considered load-bearing.

minor comments (2)

[§5] The abstract and §5 state that GC mass fraction is more robust than number fraction, but the quantitative difference (e.g., correlation coefficients) is not shown in a dedicated panel or table.
[Figures 6-7] Figure captions for the correlation plots should explicitly state the number of CMGs used and whether error bars reflect Poisson or model uncertainties.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the thoughtful and constructive report. The comments highlight important points regarding the robustness of our synthetic GC model and the identification of relic analogs. We address each major comment below. Where appropriate, we have made partial revisions to clarify limitations, add references to prior model validations, and expand the discussion of future observational tests. The core simulation-based analysis remains unchanged as it is internally consistent with TNG100.

read point-by-point responses

Referee: §4 (Results on relic identification): the claim that three specific CMGs are strong massive-relic analogs rests on the synthetic GC model producing realistic in-situ fractions, metallicity spreads, and radial profiles. The manuscript presents only internal TNG100 outputs and does not compare these quantities to observed GC systems in confirmed relics (e.g., NGC 1277, Mrk 1216), leaving open whether the reported signatures are robust or artifacts of the assignment rules.

Authors: We agree that direct comparison to observed GC systems in confirmed relics (NGC 1277, Mrk 1216) would provide stronger external validation. Our study is simulation-focused, deriving signatures from TNG100 assembly histories and the GC assignment model to identify consistent early-formation indicators. The three CMGs are selected based on internal metrics (high in-situ GC fractions, narrow metallicity spreads, compact profiles) that align with relic expectations from the simulation. In the revised manuscript we have added a dedicated paragraph in §4 and the conclusions explicitly noting the absence of direct observational matches, framing our results as predictions to be tested with future data on real relics, and emphasizing that the signatures are emergent from the simulation rather than claimed as universally robust. revision: partial
Referee: §3 (GC formation and evolution model): the assignment of clusters to stellar particles according to age and local conditions is central to all downstream claims, yet no external validation against observed GC metallicity distributions or spatial profiles in compact galaxies is provided. Without such a test, the assertion that GC spatial profiles trace stripping processes cannot be considered load-bearing.

Authors: The GC formation model in §3 follows established prescriptions (tied to stellar particle age, local density, and metallicity) previously implemented and tested in TNG-based studies for reproducing global GC properties such as mass functions and metallicity distributions. We do not introduce new external validation here because the work centers on applying the model to CMGs to explore assembly diagnostics. The correlation between stripped fraction and ex-situ GC extent is presented as an emergent simulation result and a proposed diagnostic, not a confirmed observational tool. In revision we have expanded §3 with additional references to prior model tests, clarified the assumptions, and softened the language around the stripping signature to indicate it as a testable prediction rather than a load-bearing claim. revision: partial

Circularity Check

0 steps flagged

No circularity: results are direct simulation outputs

full rationale

The paper applies a pre-existing GC formation model to TNG100 stellar particles and reports emergent properties (in-situ fractions, metallicity spreads, spatial profiles) as diagnostics for relic galaxies. No equation or step defines a quantity in terms of itself, renames a fitted parameter as a prediction, or reduces the central claim to a self-citation chain. The three CMG analogs and the stripped-fraction correlation are computed outputs, not tautological re-statements of the model's inputs.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The work rests on the standard assumptions of the Illustris TNG100 cosmological simulation and the chosen synthetic GC formation prescription; no new free parameters or invented entities are introduced in the abstract.

axioms (1)

domain assumption GCs can be assigned to stellar particles according to age and local conditions to produce realistic positional, kinematic, and chemical properties.
This is the core modeling step invoked to generate the GC catalogs used for all comparisons.

pith-pipeline@v0.9.0 · 5580 in / 1231 out tokens · 38864 ms · 2026-05-13T18:06:42.783542+00:00 · methodology

discussion (0)

Lean theorems connected to this paper

Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

IndisputableMonolith/Constants.lean (c=1, ℏ, G as φ-powers) reality_from_one_distinction contradicts

?

contradicts
CONTRADICTS: the theorem conflicts with this paper passage, or marks a claim that would need revision before publication.

We assume the Planck Collaboration et al. (2016) parameters... H0 = 67.74 km s−1 Mpc−1, Ωm = 0.30, ΩΛ = 0.69

What do these tags mean?

matches: The paper's claim is directly supported by a theorem in the formal canon.
supports: The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
extends: The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
uses: The paper appears to rely on the theorem as machinery.
contradicts: The paper's claim conflicts with a theorem or certificate in the canon.
unclear: Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.

Reference graph

Works this paper leans on

61 extracted references · 61 canonical work pages · 2 internal anchors

[1]

A., Chies-Santos, A

Alamo-Mart´ ınez, K. A., Chies-Santos, A. L., Beasley, M. A., et al. 2021, MNRAS, 503, 2406, doi: 10.1093/mnras/stab538

work page doi:10.1093/mnras/stab538 2021
[2]

2024, Nature Astronomy, 8, 1310, doi: 10.1038/s41550-024-02327-3

Angeloudi, E., Falc´ on-Barroso, J., Huertas-Company, M., et al. 2024, Nature Astronomy, 8, 1310, doi: 10.1038/s41550-024-02327-3

work page doi:10.1038/s41550-024-02327-3 2024
[3]

M., P´ erez-Gonz´ alez, P

Barro, G., Faber, S. M., P´ erez-Gonz´ alez, P. G., et al. 2013, ApJ, 765, 104, doi: 10.1088/0004-637X/765/2/104

work page doi:10.1088/0004-637x/765/2/104 2013
[4]

2015, MNRAS, 453, 357, doi: 10.1093/mnras/stv1661

Bastian, N., & Lardo, C. 2015, MNRAS, 453, 357, doi: 10.1093/mnras/stv1661

work page doi:10.1093/mnras/stv1661 2015
[5]

Beasley, M. A. 2020, Globular Cluster Systems and Galaxy Formation, 245–277, doi: 10.1007/978-3-030-38509-5 9

work page doi:10.1007/978-3-030-38509-5 2020
[6]

A., Trujillo, I., Leaman, R., & Montes, M

Beasley, M. A., Trujillo, I., Leaman, R., & Montes, M. 2018, Nature, 555, 483, doi: 10.1038/nature25756

work page doi:10.1038/nature25756 2018
[7]

P., Cantiello, M., & Peng, E

Blakeslee, J. P., Cantiello, M., & Peng, E. W. 2010, ApJ, 710, 51, doi: 10.1088/0004-637X/710/1/51

work page doi:10.1088/0004-637x/710/1/51 2010
[8]

P., Cho, H., Peng, E

Blakeslee, J. P., Cho, H., Peng, E. W., et al. 2012, ApJ, 746, 88, doi: 10.1088/0004-637X/746/1/88

work page doi:10.1088/0004-637x/746/1/88 2012
[9]

P., & Strader, J

Brodie, J. P., & Strader, J. 2006, ARA&A, 44, 193, doi: 10.1146/annurev.astro.44.051905.092441

work page doi:10.1146/annurev.astro.44.051905.092441 2006
[10]

M., Alatalo, K., et al

Cappellari, M., McDermid, R. M., Alatalo, K., et al. 2013, MNRAS, 432, 1862, doi: 10.1093/mnras/stt644

work page doi:10.1093/mnras/stt644 2013
[11]

P., Ennis, A

Caso, J. P., Ennis, A. I., & De B´ ortoli, B. J. 2024, MNRAS, 527, 6993, doi: 10.1093/mnras/stad3602

work page doi:10.1093/mnras/stad3602 2024
[12]

Chen, Y., & Gnedin, O. Y. 2022, MNRAS, 514, 4736, doi: 10.1093/mnras/stac1651 —. 2023, MNRAS, 522, 5638, doi: 10.1093/mnras/stad1328 —. 2024, MNRAS, 527, 3692, doi: 10.1093/mnras/stad3345

work page doi:10.1093/mnras/stac1651 2022
[13]

L., Larsen, S

Chies-Santos, A. L., Larsen, S. S., Cantiello, M., et al. 2012, A&A, 539, A54, doi: 10.1051/0004-6361/201117169

work page doi:10.1051/0004-6361/201117169 2012
[14]

P., Chies-Santos, A

Cho, H., Blakeslee, J. P., Chies-Santos, A. L., et al. 2016, ApJ, 822, 95, doi: 10.3847/0004-637X/822/2/95

work page doi:10.3847/0004-637x/822/2/95 2016
[15]

Choksi, N., & Gnedin, O. Y. 2019, MNRAS, 488, 5409, doi: 10.1093/mnras/stz2097

work page doi:10.1093/mnras/stz2097 2019
[16]

Y., & Li, H

Choksi, N., Gnedin, O. Y., & Li, H. 2018, MNRAS, 480, 2343, doi: 10.1093/mnras/sty1952

work page doi:10.1093/mnras/sty1952 2018
[17]

2005, ApJ, 626, 680, doi: 10.1086/430104

Daddi, E., Renzini, A., Pirzkal, N., et al. 2005, ApJ, 626, 680, doi: 10.1086/430104

work page doi:10.1086/430104 2005
[18]

J., & Sohn, J

Damjanov, I., Geller, M. J., & Sohn, J. 2025, ApJ, 982, 178, doi: 10.3847/1538-4357/ada3c5

work page doi:10.3847/1538-4357/ada3c5 2025
[19]

J., Abraham, R

Damjanov, I., McCarthy, P. J., Abraham, R. G., et al. 2009, ApJ, 695, 101, doi: 10.1088/0004-637X/695/1/101

work page doi:10.1088/0004-637x/695/1/101 2009
[20]

A., Norris, M

Davison, T. A., Norris, M. A., Leaman, R., et al. 2021, MNRAS, 507, 3089, doi: 10.1093/mnras/stab2362

work page doi:10.1093/mnras/stab2362 2021
[21]

doi:10.1111/j.1365-2966.2009.15598.x , archivePrefix =

Dolag, K., Borgani, S., Murante, G., & Springel, V. 2009, MNRAS, 399, 497, doi: 10.1111/j.1365-2966.2009.15034.x

work page doi:10.1111/j.1365-2966.2009.15034.x 2009
[22]

2020, A&A, 637, A27, doi: 10.1051/0004-6361/202037686 Ferr´ e-Mateu, A., Forbes, D

Fahrion, K., Lyubenova, M., Hilker, M., et al. 2020, A&A, 637, A27, doi: 10.1051/0004-6361/202037686 Ferr´ e-Mateu, A., Forbes, D. A., Romanowsky, A. J., Janz, J., & Dixon, C. 2018, MNRAS, 473, 1819, doi: 10.1093/mnras/stx2442 Ferr´ e-Mateu, A., Trujillo, I., Mart´ ın-Navarro, I., et al. 2017, Monthly Notices of the Royal Astronomical Society, 467, 1929, ...

work page doi:10.1051/0004-6361/202037686 2020
[23]

A., & Remus, R.-S

Forbes, D. A., & Remus, R.-S. 2018, Monthly Notices of the Royal Astronomical Society, 479, 4760, doi: 10.1093/mnras/sty1767

work page doi:10.1093/mnras/sty1767 2018
[24]

Kelson, D. D. 2014, ApJ, 788, 72, doi: 10.1088/0004-637X/788/1/72

work page doi:10.1088/0004-637x/788/1/72 2014
[25]

2018, MNRAS, 474, 3976, doi: 10.1093/mnras/stx3078

Genel, S., Nelson, D., Pillepich, A., et al. 2018, MNRAS, 474, 3976, doi: 10.1093/mnras/stx3078

work page doi:10.1093/mnras/stx3078 2018
[26]

Gieles, M., & Gnedin, O. Y. 2023, MNRAS, 522, 5340, doi: 10.1093/mnras/stad1287 Gr` ebol-Tom` as, P., Ferr´ e-Mateu, A., & Dom´ ınguez-S´ anchez, H. 2023a, MNRAS, 526, 4024, doi: 10.1093/mnras/stad2973 —. 2023b, MNRAS, 526, 4024, doi: 10.1093/mnras/stad2973

work page doi:10.1093/mnras/stad1287 2023
[27]

E., Morningstar, W., Gnedin, O

Harris, W. E., Morningstar, W., Gnedin, O. Y., et al. 2014, ApJ, 797, 128, doi: 10.1088/0004-637X/797/2/128

work page doi:10.1088/0004-637x/797/2/128 2014
[28]

P., & Geller, M

Huchra, J. P., & Geller, M. J. 1982, ApJ, 257, 423, doi: 10.1086/160000

work page doi:10.1086/160000 1982
[29]

Kang, J., & Lee, M. G. 2021, ApJ, 914, 20, doi: 10.3847/1538-4357/abf433

work page doi:10.3847/1538-4357/abf433 2021
[30]

V., & Gnedin, O

Kravtsov, A. V., & Gnedin, O. Y. 2005, ApJ, 623, 650, doi: 10.1086/428636

work page doi:10.1086/428636 2005
[31]

Kruijssen, J. M. D. 2015, Monthly Notices of the Royal Astronomical Society, 454, 1658, doi: 10.1093/mnras/stv2026

work page doi:10.1093/mnras/stv2026 2015
[32]

S., Strader, J., & Brodie, J

Larsen, S. S., Strader, J., & Brodie, J. P. 2012, A&A, 544, L14, doi: 10.1051/0004-6361/201219897

work page doi:10.1051/0004-6361/201219897 2012
[33]

2019, ApJS, 240, 2, doi: 10.3847/1538-4365/aaecd4

Lee, S.-Y., Chung, C., & Yoon, S.-J. 2019, ApJS, 240, 2, doi: 10.3847/1538-4365/aaecd4

work page doi:10.3847/1538-4365/aaecd4 2019
[34]

Li, H., & Gnedin, O. Y. 2019, MNRAS, 486, 4030, doi: 10.1093/mnras/stz1114

work page doi:10.1093/mnras/stz1114 2019
[35]

2023, A&A, 669, A95, doi: 10.1051/0004-6361/202243616

Lisiecki, K., Ma lek, K., Siudek, M., et al. 2023, A&A, 669, A95, doi: 10.1051/0004-6361/202243616

work page doi:10.1051/0004-6361/202243616 2023
[36]

T., Chies-Santos, A

Moura, M. T., Chies-Santos, A. L., Furlanetto, C., Zhu, L., & Canossa-Gosteinski, M. A. 2024, MNRAS, 528, 353, doi: 10.1093/mnras/stae013

work page doi:10.1093/mnras/stae013 2024
[37]

Furlanetto, C., & Beasley, M. A. 2025, A&A, 704, A287, doi: 10.1051/0004-6361/202555494

work page doi:10.1051/0004-6361/202555494 2025
[38]

L., & Gnedin, O

Muratov, A. L., & Gnedin, O. Y. 2010, ApJ, 718, 1266, doi: 10.1088/0004-637X/718/2/1266 14 GCs in compact systems

work page doi:10.1088/0004-637x/718/2/1266 2010
[39]

H., & Ostriker, J

Naab, T., Johansson, P. H., & Ostriker, J. P. 2009, ApJL, 699, L178, doi: 10.1088/0004-637X/699/2/L178

work page doi:10.1088/0004-637x/699/2/l178 2009
[40]

First results from the IllustrisTNG simulations: the galaxy color bimodality

Nelson, D., Pillepich, A., Springel, V., et al. 2018, MNRAS, 475, 624, doi: 10.1093/mnras/stx3040

work page internal anchor Pith review doi:10.1093/mnras/stx3040 2018
[41]

2019, Computational Astrophysics and Cosmology, 6, 2, doi: 10.1186/s40668-019-0028-x

Nelson, D., Springel, V., Pillepich, A., et al. 2019, Computational Astrophysics and Cosmology, 6, 2, doi: 10.1186/s40668-019-0028-x

work page doi:10.1186/s40668-019-0028-x 2019
[42]

2010, ApJ, 725, 2312, doi: 10.1088/0004-637X/725/2/2312

Burkert, A. 2010, ApJ, 725, 2312, doi: 10.1088/0004-637X/725/2/2312

work page doi:10.1088/0004-637x/725/2/2312 2010
[43]

W., Jord´ an, A., Cˆ ot´ e, P., et al

Peng, E. W., Jord´ an, A., Cˆ ot´ e, P., et al. 2008, ApJ, 681, 197, doi: 10.1086/587951

work page doi:10.1086/587951 2008
[44]

2018b, MNRAS, 473, 4077, doi: 10.1093/mnras/stx2656

Pillepich, A., Springel, V., Nelson, D., et al. 2018, MNRAS, 473, 4077, doi: 10.1093/mnras/stx2656

work page internal anchor Pith review doi:10.1093/mnras/stx2656 2018
[45]

2019, MNRAS, 490, 3196, doi: 10.1093/mnras/stz2338

Pillepich, A., Nelson, D., Springel, V., et al. 2019, MNRAS, 490, 3196, doi: 10.1093/mnras/stz2338 Planck Collaboration, Ade, P. A. R., Aghanim, N., et al. 2016, A&A, 594, A13, doi: 10.1051/0004-6361/201525830

work page doi:10.1093/mnras/stz2338 2019
[46]

W., Kruijssen, J

Reina-Campos, M., Keller, B. W., Kruijssen, J. M. D., et al. 2022, MNRAS, 517, 3144, doi: 10.1093/mnras/stac1934

work page doi:10.1093/mnras/stac1934 2022
[47]

The merger rate of galaxies in the Illustris Simulation: a comparison with observations and semi-empirical models

Rodriguez-Gomez, V., Genel, S., Vogelsberger, M., et al. 2015, MNRAS, 449, 49, doi: 10.1093/mnras/stv264

work page Pith review doi:10.1093/mnras/stv264 2015
[48]

V., et al

Rodriguez-Gomez, V., Pillepich, A., Sales, L. V., et al. 2016a, MNRAS, 458, 2371, doi: 10.1093/mnras/stw456 —. 2016b, MNRAS, 458, 2371, doi: 10.1093/mnras/stw456

work page doi:10.1093/mnras/stw456
[49]

, year = 1976, month = jan, volume =

Schechter, P. 1976, ApJ, 203, 297, doi: 10.1086/154079

work page doi:10.1086/154079 1976
[50]

1978, ApJ, 225, 357, doi: 10.1086/156499

Searle, L., & Zinn, R. 1978, ApJ, 225, 357, doi: 10.1086/156499

work page doi:10.1086/156499 1978
[51]

2021, A&A, 646, A28, doi: 10.1051/0004-6361/202038936

Spiniello, C., Tortora, C., D’Ago, G., et al. 2021, A&A, 646, A28, doi: 10.1051/0004-6361/202038936

work page doi:10.1051/0004-6361/202038936 2021
[52]

2024, MNRAS, 527, 8793, doi: 10.1093/mnras/stad3703

Spiniello, C., D’Ago, G., Coccato, L., et al. 2024, MNRAS, 527, 8793, doi: 10.1093/mnras/stad3703

work page doi:10.1093/mnras/stad3703 2024
[53]

doi:10.1111/j.1365-2966.2009.15598.x , archivePrefix =

Springel, V. 2010, MNRAS, 401, 791, doi: 10.1111/j.1365-2966.2009.15715.x

work page doi:10.1111/j.1365-2966.2009.15715.x 2010
[54]

Springel, V., White, S. D. M., Tormen, G., & Kauffmann, G. 2001, MNRAS, 328, 726, doi: 10.1046/j.1365-8711.2001.04912.x

work page doi:10.1046/j.1365-8711.2001.04912.x 2001
[55]

2018, MNRAS, 475, 676, doi: 10.1093/mnras/stx3304

Springel, V., Pakmor, R., Pillepich, A., et al. 2018, MNRAS, 475, 676, doi: 10.1093/mnras/stx3304

work page doi:10.1093/mnras/stx3304 2018
[56]

Forbes, D. A. 2005, AJ, 130, 1315, doi: 10.1086/432717

work page doi:10.1086/432717 2005
[57]

J., de Lorenzo-C´ aceres, A., et al

Trujillo, I., Cenarro, A. J., de Lorenzo-C´ aceres, A., et al. 2009, ApJL, 692, L118, doi: 10.1088/0004-637X/692/2/L118

work page doi:10.1088/0004-637x/692/2/l118 2009
[58]

2014, ApJL, 780, L20, doi: 10.1088/2041-8205/780/2/L20

Trujillo, I., Ferr´ e-Mateu, A., Balcells, M., Vazdekis, A., & S´ anchez-Bl´ azquez, P. 2014, ApJL, 780, L20, doi: 10.1088/2041-8205/780/2/L20

work page doi:10.1088/2041-8205/780/2/l20 2014
[59]

P., Forbes, D

Usher, C., Brodie, J. P., Forbes, D. A., et al. 2019, MNRAS, 490, 491, doi: 10.1093/mnras/stz2596 van der Wel, A., Franx, M., van Dokkum, P. G., et al. 2014, The Astrophysical Journal, 788, 28, doi: 10.1088/0004-637X/788/1/28

work page doi:10.1093/mnras/stz2596 2019
[60]

2025, arXiv e-prints, arXiv:2507.18699, doi: 10.48550/arXiv.2507.18699 Yıldırım, A., van den Bosch, R

Vanzella, E., Messa, M., Adamo, A., et al. 2025, arXiv e-prints, arXiv:2507.18699, doi: 10.48550/arXiv.2507.18699 Yıldırım, A., van den Bosch, R. C. E., van de Ven, G., et al. 2017, Monthly Notices of the Royal Astronomical Society, 468, 4216, doi: 10.1093/mnras/stx732

work page doi:10.48550/arxiv.2507.18699 2025
[61]

L., Moura, M

Zhu, L., Chies-Santos, A. L., Moura, M. T., & Shi, H. 2025, A&A, 698, A195, doi: 10.1051/0004-6361/202453083 15 Micheli T. Moura APPENDIX 16 GCs in compact systems T able 1.Global properties of the GC systems for each host galaxy. The first column lists the host IDs. Columns 2 and 3 show thein-situandex-situGC fractions computed by number (N GC), while co...

work page doi:10.1051/0004-6361/202453083 2025