pith. sign in

arxiv: 2606.10558 · v1 · pith:CQAPWFKLnew · submitted 2026-06-09 · 🌌 astro-ph.GA

Hector Galaxy Survey: Linking the low- and high-mass ends of the initial mass function in star-forming galaxies

Diego Salvador , Andrew Hopkins , Matt Owers , Ignacio Mart\'in-Navarro , Gabriella Quattropani , Pratyush Kumar Das , Mina Pak , Scott Croom
show 25 more authors
Julia Bryant Tereza Jerabkova Karl Glazebrook Andrei Ristea Madusha Gunawardhana Sarah Sweet Kyuseok Oh Jong Chul Lee Joon Hyeop Lee Caroline Foster Tayyaba Zafar Yifan Mai Susie Tuntipong Jesse van de Sande Stefania Barsanti Joss Bland-Hawthorn Matthew Colless Robert Content Tony Farrell Jon Lawrence Seong-sik Min Sree Oh Naveen Pai Ayoan Salim Sadman Ross Zhelem
This is my paper

Pith reviewed 2026-06-27 12:38 UTC · model grok-4.3

classification 🌌 astro-ph.GA
keywords initial mass functionIMF slopesstar-forming galaxiesstellar metallicityHector surveyKennicutt diagnosticgalaxy evolutionstellar populations
0
0 comments X

The pith

The IMF in star-forming galaxies is not universal, with low- and high-mass slopes showing weak correlation and ties to galaxy properties.

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

This paper measures both the low-mass and high-mass ends of the initial mass function simultaneously in 214 star-forming galaxies from the Hector survey. Low-mass slopes come from fitting absorption features in stellar population models with extended star formation histories. High-mass slopes use the Kennicutt diagnostic comparing H-alpha equivalent width and g-r color to model predictions. Results show diverse IMF shapes, a weak correlation between the two slopes, and links of both to stellar mass, star formation rate, and metallicity. The low-mass end depends mainly on metallicity while the high-mass end links to mass and recent activity, pointing to different shaping timescales.

Core claim

The first simultaneous analysis of both IMF ends in star-forming galaxies reveals substantial diversity in shapes and a weak but robust correlation between low- and high-mass slopes. Both slopes correlate with stellar mass, star formation activity, and [M/H], with higher values linked to bottom-heavy and top-heavy IMFs. Partial correlations show the low-mass slope driven primarily by metallicity and the high-mass slope by stellar mass and recent star formation. Since the low-mass slope averages over long timescales and the high-mass over recent ones, the processes likely occur on decoupled timescales. This challenges IMF universality and requires flexible prescriptions in galaxy evolution mo

What carries the argument

Simultaneous IMF slope estimation via stellar population synthesis fitting of absorption features for the low-mass end and the Kennicutt diagnostic using H-alpha and color for the high-mass end.

Load-bearing premise

The models used to fit the spectral features and the Kennicutt diagnostic recover the true IMF slopes accurately, without large biases from dust, complex star formation histories, or other unaccounted galaxy properties.

What would settle it

Independent measurements of the IMF slopes in the same galaxies using methods such as gravitational lensing or stellar dynamics that show either no correlation between the ends or no dependence on mass and metallicity would falsify the central findings.

Figures

Figures reproduced from arXiv: 2606.10558 by Andrei Ristea, Andrew Hopkins, Ayoan Salim Sadman, Caroline Foster, Diego Salvador, Gabriella Quattropani, Ignacio Mart\'in-Navarro, Jesse van de Sande, Jong Chul Lee, Jon Lawrence, Joon Hyeop Lee, Joss Bland-Hawthorn, Julia Bryant, Karl Glazebrook, Kyuseok Oh, Madusha Gunawardhana, Matthew Colless, Matt Owers, Mina Pak, Naveen Pai, Pratyush Kumar Das, Robert Content, Ross Zhelem, Sarah Sweet, Scott Croom, Seong-Sik Min, Sree Oh, Stefania Barsanti, Susie Tuntipong, Tayyaba Zafar, Tereza Jerabkova, Tony Farrell, Yifan Mai.

Figure 1
Figure 1. Figure 1: Panel a) shows the stellar mass distribution of the sample; panel b) displays the SDSS r-band magnitudes; panel c) presents the effective radii; and panel d) shows the logarithmic Hα luminosity (in Watts) as a function of redshift (z). Panel e) illustrates the relation between Hα luminosity (and SFR) and stellar mass, with points colour-coded by the median spectral S/N. The S/N was computed as the median r… view at source ↗
Figure 2
Figure 2. Figure 2: Illustration of the constraining power of IMF-sensitive spectral features (from left to right: Mgb5177, Fe5270, Fe5335, TiO1, and TiO2) for galaxy W17670457407415. The black curve shows the best-fitting model spectrum obtained from the MCMC module. The coloured curves represent model spectra where all parameters are fixed to their best-fitting values, except for the IMF slope, which is varied. The colour s… view at source ↗
Figure 3
Figure 3. Figure 3: Example of five IMF-sensitive absorption features in the spectrum of galaxy W17670457407415 (black line). The grey shaded regions show the ±1σ observational uncertainty of the spectrum. The red line indicates the best-fitting model (median of the posterior MCMC samples), while the orange lines correspond to 50 randomly drawn MCMC realisations (after the burn-in) illustrating model variance. The shaded blue… view at source ↗
Figure 4
Figure 4. Figure 4: Posterior distributions for the stellar population parameters [M/H], [Mg/Fe] and low-mass end IMF slope (αlow), obtained from the Bayesian full-index fitting method applied to ten SFH realisations per galaxy for galaxy W17670457407415. The vertical dashed lines indicate the 16th to 84th per￾centile uncertainties derived by combining the posteriors from all realisa￾tions. The red cross marks the selected pa… view at source ↗
Figure 5
Figure 5. Figure 5: Distribution of galaxies in the log(EWHα )vs g − r diagnostic plane. The black grid shows model predictions from PÉGASE.3, spanning a range of high-mass IMF slopes (α from –1.5 to –4.0). For reference, models with αhigh = −3, −2.35, and −2 (lines from left to right) are highlighted with thicker black lines. Our galaxy sample is overlaid points coloured by αhigh. The red cross in the lower left corner illus… view at source ↗
Figure 6
Figure 6. Figure 6: Shapes of the IMF in logarithmic space for a representative subset of galaxies in our sample. Each grey line corresponds a different galaxy, showing the IMF slope from the low-mass end (0.08 to 1 M⊙) to the high-mass end (1 to 120 M⊙). The orange dashed vertical line indicates the transition between low- and high-mass ends. The dashed black line represents the canonical Salpeter IMF (αlow = αhigh = −2.35).… view at source ↗
Figure 7
Figure 7. Figure 7: Low-mass-end IMF slope, αlow, vs high-mass-end IMF slope, αhigh, for all 214 galaxies in our sample, colour-coded by total stellar mass. The parameter space is divided into four regions: LL, LH, HL, and HH, indicating all possible combinations of low- and high-mass end slope values. The Milky Way is marked as an orange galaxy symbol, adopting the IMF from Kroupa (2001). Blue and green squares show results … view at source ↗
Figure 8
Figure 8. Figure 8: Normalised stellar mass distributions for galaxies in each IMF quadrant. All four IMF types—LL (purple), LH (red), HL (blue), and HH (green) are well represented in the sample. LL galaxies tend to have lower stellar masses, while HH galaxies are the most massive on average. HL and LH types exhibit intermediate mass distributions with similar shapes. then assign the bin’s slope the IMF slope corresponding t… view at source ↗
Figure 9
Figure 9. Figure 9: The relation between αX withlog(L(Hα)), where αX generically represents either αlow or αhigh. Panel a) displays the measurements of αhigh with orange points showing the binned values, the orange dotted line the best-fit relation, and the shaded orange region its bootstrap uncertainty. For reference, the best-fit relation for αlow from panel b) is over-plotted as a purple dotted line. Panel b) shows αlow wi… view at source ↗
Figure 10
Figure 10. Figure 10: Binned measurements of αX as a function of the Hα luminosity surface density, ΣL(Hα) , where αX generically represents either αlow or αhigh. Purple points correspond to the individual galaxy measurements for αlow, and orange points correspond to those for αhigh, shown for reference. Dashed lines indicate the best-fit relations for each slope, and the shaded regions represent the corresponding bootstrap un… view at source ↗
Figure 11
Figure 11. Figure 11: Panels a) and b) show αX as a function of [M/H] and [Mg/Fe], respectively, where αX generically represents either αlow or αhigh. The grey shaded regions in panels a) and b) indicate the approximate location of the results from MN24, which trace the trend of αlow with chemical abundances in individual Voronoi bins of the star-forming galaxy NGC 3351. Panel c) presents the stellar mass-metallicity relation,… view at source ↗
Figure 12
Figure 12. Figure 12: shows the violin+box plot of the distribution of ∆α = αlow([Ti/Fe]=X) − αlow([Ti/Fe]=0), for X =[−0.25, −0.15, −0.05, 0.05, 0.15, 0.25]. The distributions are all sharply peaked around zero, with a global mean ⟨∆α⟩ = 0.028 and a small interquartile scatter (IQR ≃ 0.074, corresponding to a robust dispersion of σrobust = IQR/1.349 ≃ 0.055). This demonstrates that αlow is robust to reasonable variations in t… view at source ↗
Figure 14
Figure 14. Figure 14: Relation between αlow and the stellar velocity dispersion (σ) for the quiescent galaxy sample. Each point represents an individual galaxy, colour-coded by stellar mass. The dashed blue and red lines show the uni￾modal and bimodal IMF–σ relations from Ferreras et al. (2012), respectively. The solid lines correspond to the relations from La Barbera et al. (2013): bi￾modal 2SSP (green), bimodal 2SSP+X/Fe (bl… view at source ↗
Figure 13
Figure 13. Figure 13: Comparison of αlow derived with and without specific spectral features included in the MCMC fitting. Panel a) shows results with and without NaD, panel b) with and without TiO1, and panel c) with and without TiO2. Orange points correspond to individual galaxies, and the purple line indicates the one-to-one relation. Overall, including NaD or omitting TiO features systematically shifts αlow toward more neg… view at source ↗
Figure 15
Figure 15. Figure 15: Effect of the upper stellar mass limit (mmax) parameter on PÉGASE on our results. Left: Model grids in the log(EWH¸) vs g − r plane for mmax = 100 M⊙ (red dashed), 120 M⊙ (green solid), and 150 M⊙ (blue dashed). Right: Differences in the recovered IMF slopes relative to the fiducial mmax = 120 M⊙ model, shown for mmax = 100 M⊙ (top) and mmax = 150 M⊙ (bottom). Orange points correspond to individual galaxi… view at source ↗
Figure 16
Figure 16. Figure 16: Comparison between logarithmic SFRs derived assuming a Salpeter IMF (x-axis) and SFRs consistent with the measured IMF (y-axis). Points are colour-coded by αhigh. The red dashed line shows the one-to-one relation. The difference, ∆ = log(SFRIMF) − log(SFRSalpeter), has a mean of −0.6 dex and a standard deviation of 0.445 dex, suggesting that variations in the IMF can significantly impact the inferred SFR … view at source ↗
read the original abstract

The stellar initial mass function (IMF) is a fundamental ingredient in galaxy evolution, linking observed integrated light to galaxy properties. Constraining the full IMF shape beyond the Milky Way remains challenging, as most studies focus either on the low-mass end of quiescent galaxies or the high-mass end of star-forming galaxies. Here we present the first simultaneous analysis of both ends of the IMF in 214 star-forming galaxies from the Hector survey. We estimate the low-mass end slope using a stellar population approach that fits IMF-sensitive absorption features with extended star formation histories, while the high-mass end slope is derived via the Kennicutt diagnostic, which compares the observed H-alpha equivalent width and g-r colour with stellar population synthesis model predictions. We find substantial diversity in IMF shapes and a weak but statistically robust correlation between the low- and high-mass IMF slopes. Both IMF slopes show significant correlations with stellar mass, star formation activity, and stellar metallicity ([M/H]). In general, higher stellar mass, stronger star formation activity, and higher metallicity are associated with both bottom-heavy and top-heavy IMFs. Partial correlation analysis reveals that the low-mass end slope is primarily driven by [M/H], whereas the high-mass end is mainly linked to stellar mass and recent star formation. Because the low-mass end slope traces the IMF over long-term averages and the high-mass end slope captures only recent star formation, the processes shaping each end likely occur over different and possibly decoupled timescales. Our findings challenge the universality of the IMF and emphasise the need for galaxy evolution and stellar population models to incorporate a flexible IMF prescription. Accounting for these variations is essential to build an IMF-consistent picture of galaxy evolution across cosmic time.

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

3 major / 2 minor

Summary. The manuscript analyzes the initial mass function (IMF) in 214 star-forming galaxies from the Hector Galaxy Survey. It employs stellar population synthesis (SPS) modeling to constrain the low-mass IMF slope from absorption features with extended star-formation histories, and the Kennicutt diagnostic (Hα equivalent width vs. g-r color) for the high-mass slope. The authors report substantial diversity in IMF shapes, a weak but robust correlation between low- and high-mass slopes, and correlations of both slopes with stellar mass, star formation activity, and metallicity. Partial correlation analysis suggests different drivers for each end, implying decoupled timescales.

Significance. If the IMF slope measurements are free from significant systematic biases, the results would be significant for challenging the assumption of a universal IMF and for requiring flexible IMF prescriptions in galaxy evolution models. The simultaneous constraint on both ends of the IMF in a large sample of star-forming galaxies is novel, though the correlations are described as weak.

major comments (3)
  1. [Abstract] Abstract: The central claims of diversity, low-high slope correlation, and trends with mass/SF/metallicity rest on accurate recovery of true IMF slopes, but the abstract (and presumably the methods) provides no quantitative validation such as mock recovery fractions, bias maps, or tests for residual degeneracies with dust attenuation curves and non-parametric SFH components.
  2. [Methods] Methods (SPS and Kennicutt sections): It is unclear whether the SPS fits fully marginalize over flexible recent bursts on top of extended SFH or varied dust laws; without this, the recovered slopes may covary with the same observables (mass, [M/H], SFR) used in the partial correlation analysis, undermining the reported drivers.
  3. [Results] Results (partial correlation analysis): The claim that low-mass slope is primarily driven by [M/H] while high-mass is linked to mass and recent SF requires demonstration that the two IMF estimators are not sharing systematic errors from unmodeled galaxy properties; no such cross-check is described.
minor comments (2)
  1. [Abstract] The abstract would be strengthened by reporting the actual correlation coefficients, p-values, and sample selection criteria rather than qualitative descriptors.
  2. Notation for the low-mass and high-mass slopes should be defined consistently and early (e.g., Γ_low and Γ_high) to aid readability.

Simulated Author's Rebuttal

3 responses · 0 unresolved

We thank the referee for their careful reading and constructive feedback on our manuscript. We address each major comment below. Where the concerns identify gaps in validation or clarification, we have revised the manuscript accordingly to strengthen the presentation of our results on IMF diversity and correlations.

read point-by-point responses

  1. Referee: [Abstract] Abstract: The central claims of diversity, low-high slope correlation, and trends with mass/SF/metallicity rest on accurate recovery of true IMF slopes, but the abstract (and presumably the methods) provides no quantitative validation such as mock recovery fractions, bias maps, or tests for residual degeneracies with dust attenuation curves and non-parametric SFH components.

    Authors: We agree that explicit quantitative validation strengthens the central claims. While the methods section outlines the SPS and Kennicutt approaches and notes internal consistency checks, we did not include detailed mock recovery statistics or bias maps in the submitted version. We have added a new appendix with mock tests showing recovery fractions and bias assessments for both IMF estimators, including tests varying dust laws and SFH parametrizations. The abstract has been updated to reference these validations. revision: yes

  2. Referee: [Methods] Methods (SPS and Kennicutt sections): It is unclear whether the SPS fits fully marginalize over flexible recent bursts on top of extended SFH or varied dust laws; without this, the recovered slopes may covary with the same observables (mass, [M/H], SFR) used in the partial correlation analysis, undermining the reported drivers.

    Authors: The SPS modeling uses extended SFHs with multiple age bins to capture variations, but does not fully marginalize over arbitrary recent bursts or all alternative dust attenuation curves. This is a valid concern for potential covariances. We have revised the methods section to explicitly state the SFH and dust assumptions, added sensitivity tests marginalizing over additional burst parameters and dust laws, and included a discussion of how these affect the partial correlations. The Kennicutt diagnostic section was clarified similarly. revision: partial

  3. Referee: [Results] Results (partial correlation analysis): The claim that low-mass slope is primarily driven by [M/H] while high-mass is linked to mass and recent SF requires demonstration that the two IMF estimators are not sharing systematic errors from unmodeled galaxy properties; no such cross-check is described.

    Authors: The partial correlation analysis controls for inter-variable dependencies to identify primary drivers. To directly address potential shared systematics between the two independent IMF estimators, we have added cross-checks in the results section, including sample splits by metallicity and SFR, residual analysis, and comparison of IMF slopes against unmodeled properties. These confirm that the reported drivers are not dominated by shared errors from the estimators. revision: yes

Circularity Check

0 steps flagged

No significant circularity; derivation is data-driven from observations

full rationale

The paper estimates low-mass IMF slope by fitting observed absorption features to SPS models with extended SFHs, and high-mass slope via Kennicutt diagnostic on Hα EW and g-r colour. Reported correlations with mass, SFR, and metallicity are statistical outputs from these fits to independent data. No equations reduce the slopes or correlations to quantities defined by the fit itself, and no self-citation chains or ansatzes are invoked as load-bearing for the central claims. This matches the expected non-finding for a purely empirical analysis against external SPS models.

Axiom & Free-Parameter Ledger

0 free parameters · 2 axioms · 0 invented entities

The central claims rest on the accuracy of stellar population synthesis models for IMF-sensitive features and the Kennicutt diagnostic for the high-mass end; these are treated as established but introduce model-dependent assumptions not tested within the paper.

axioms (2)
  • domain assumption Stellar population synthesis models correctly map IMF-sensitive absorption features to low-mass slope when star-formation history is extended.
    Invoked in the description of the low-mass end method.
  • domain assumption The Kennicutt diagnostic isolates the high-mass IMF slope from H-alpha equivalent width and g-r colour without significant contamination.
    Invoked in the description of the high-mass end method.

pith-pipeline@v0.9.1-grok · 5990 in / 1424 out tokens · 19170 ms · 2026-06-27T12:38:08.264953+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

297 extracted references · 219 canonical work pages · 98 internal anchors

  1. [1]

    Philosophical Transactions of the Royal Society of London Series A , year = 1902, month = jan, volume =

    The Stability of a Spherical Nebula. Philosophical Transactions of the Royal Society of London Series A , year = 1902, month = jan, volume =. doi:10.1098/rsta.1902.0012 , adsurl =

    work page doi:10.1098/rsta.1902.0012 1902

  2. [2]

    An Analysis of the Shapes of Interstellar Extinction Curves. V. The IR-through-UV Curve Morphology. , keywords =. doi:10.1086/518158 , archivePrefix =. 0705.0154 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1086/518158

  3. [3]

    Metal-rich, Metal-poor: Updated Stellar Population Models for Old Stellar Systems

    Metal-rich, Metal-poor: Updated Stellar Population Models for Old Stellar Systems. , keywords =. doi:10.3847/1538-4357/aaab49 , archivePrefix =. 1801.10185 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-4357/aaab49

  4. [4]

    , keywords =

    sMILES: a library of semi-empirical MILES stellar spectra with variable [ /Fe] abundances. , keywords =. doi:10.1093/mnras/stab1001 , archivePrefix =. 2104.04822 , primaryClass =

    work page doi:10.1093/mnras/stab1001

  5. [5]

    , keywords =

    The Character of M Dwarfs. , keywords =. doi:10.1146/annurev-astro-052722-102740 , adsurl =

    work page doi:10.1146/annurev-astro-052722-102740

  6. [6]

    , year = 1997, month = jan, volume =

    Model Atmospheres of Very Low Mass Stars and Brown Dwarfs. , year = 1997, month = jan, volume =. doi:10.1146/annurev.astro.35.1.137 , adsurl =

    work page doi:10.1146/annurev.astro.35.1.137 1997

  7. [7]

    , keywords =

    The Distribution of Low-Mass Stars in the Galactic Disc. , keywords =. doi:10.1093/mnras/262.3.545 , adsurl =

    work page doi:10.1093/mnras/262.3.545

  8. [8]

    , keywords =

    The Initial Mass Function and Stellar Birthrate in the Solar Neighborhood. , keywords =. doi:10.1086/190629 , adsurl =

    work page doi:10.1086/190629

  9. [9]

    , keywords =

    The Physical Origin of the Stellar Initial Mass Function. , keywords =. doi:10.1146/annurev-astro-052622-031748 , archivePrefix =. 2404.07301 , primaryClass =

    work page doi:10.1146/annurev-astro-052622-031748

  10. [10]

    arXiv e-prints , keywords =

    Massive Star Formation at Supersolar Metallicities: Constraints on the Initial Mass Function. arXiv e-prints , keywords =. doi:10.48550/arXiv.2509.20440 , archivePrefix =. 2509.20440 , primaryClass =

    work page doi:10.48550/arxiv.2509.20440

  11. [11]

    The statistical properties of stars and their dependence on metallicity: the effects of opacity

    The statistical properties of stars and their dependence on metallicity: the effects of opacity. , keywords =. doi:10.1093/mnras/stu795 , archivePrefix =. 1405.5583 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/stu795

  12. [12]

    Multimass modelling of Milky Way globular clusters – I

    Dickson, N and Hénault-Brunet, V and Baumgardt, H and Gieles, M and Smith, P J , year=. Multimass modelling of Milky Way globular clusters – I. Implications on their stellar initial mass function above 1 M⊙ , volume=. Monthly Notices of the Royal Astronomical Society , publisher=. doi:10.1093/mnras/stad1254 , number=

    work page doi:10.1093/mnras/stad1254

  13. [13]

    , keywords =

    Evidence for a bottom-light initial mass function in massive star clusters. , keywords =. doi:10.1093/mnras/stad631 , archivePrefix =. 2303.01636 , primaryClass =

    work page doi:10.1093/mnras/stad631

  14. [14]

    , keywords =

    Quantifying the Effects of Known Unknowns on Inferred High-redshift Galaxy Properties: Burstiness, IMF, and Nebular Physics. , keywords =. doi:10.3847/1538-4357/ad187c , archivePrefix =. 2310.06781 , primaryClass =

    work page doi:10.3847/1538-4357/ad187c

  15. [15]

    Publications of the Astronomical Society of Australia , author=

    Hector Galaxy Survey: Data Processing, Quality Control and Early Science , DOI=. Publications of the Astronomical Society of Australia , author=. 2025 , pages=

    2025

  16. [16]

    , keywords =

    The cosmic evolution of metallicity from the SDSS fossil record. , keywords =. doi:10.1111/j.1365-2966.2008.13981.x , archivePrefix =. 0804.3091 , primaryClass =

    work page doi:10.1111/j.1365-2966.2008.13981.x 2008

  17. [17]

    , keywords =

    Stellar populations and physical properties of starbursts in the antennae galaxy from self-consistent modelling of MUSE spectra. , keywords =. doi:10.1093/mnras/staa2158 , archivePrefix =. 1912.08151 , primaryClass =

    work page doi:10.1093/mnras/staa2158 1912

  18. [18]

    CALIFA, the Calar Alto Legacy Integral Field Area survey. III. Second public data release. , keywords =. doi:10.1051/0004-6361/201425080 , archivePrefix =. 1409.8302 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/201425080

  19. [19]

    10.1051/0004-6361/201220582

    CALIFA, the Calar Alto Legacy Integral Field Area survey - II. First public data release⋆ , DOI= "10.1051/0004-6361/201220582", url= "https://doi.org/10.1051/0004-6361/201220582", journal =

    work page doi:10.1051/0004-6361/201220582

  20. [20]

    The Effects of Stellar Rotation. II. A Comprehensive Set of Starburst99 Models. , keywords =. doi:10.1088/0067-0049/212/1/14 , archivePrefix =. 1403.5444 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1088/0067-0049/212/1/14

  21. [21]

    and Meynet, Georges and Morisset, Christophe and Sander, Andreas A

    Hawcroft, Calum and Leitherer, Claus and Aranguré, Oskar and Chisholm, John and Ekström, Sylvia and Martinet, Sébastien and Martins, Lucimara P. and Meynet, Georges and Morisset, Christophe and Sander, Andreas A. C. and Wofford, Aida , year=. pySTARBURST99: The Next Generation of S<scp>TARBURST</scp>99 , volume=. The Astrophysical Journal Supplement Serie...

    work page doi:10.3847/1538-4365/adddb6

  22. [22]

    Dust attenuation in z $\sim$ 1 galaxies from Herschel and 3D-HST H$\alpha$ measurements

    Dust attenuation in z -0.5ex 1 galaxies from Herschel and 3D-HST H measurements. , keywords =. doi:10.1051/0004-6361/201526782 , archivePrefix =. 1507.00005 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361/201526782

  23. [23]

    , keywords =

    Dependence of the IRX- Dust Attenuation Relation on Metallicity and Environment. , keywords =. doi:10.3847/2041-8213/abc1ef , archivePrefix =. 2010.10538 , primaryClass =

    work page doi:10.3847/2041-8213/abc1ef 2041

  24. [24]

    A UBVR CCD Survey of the Magellanic Clouds

    A UBVR CCD Survey of the Magellanic Clouds. , keywords =. doi:10.1086/338286 , archivePrefix =. astro-ph/0110531 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1086/338286

  25. [25]

    Galaxy And Mass Assembly (GAMA): Linking Star Formation Histories and Stellar Mass Growth

    Galaxy And Mass Assembly (GAMA): linking star formation histories and stellar mass growth. , keywords =. doi:10.1093/mnras/stt1011 , archivePrefix =. 1306.2424 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/stt1011

  26. [26]

    Ground-based and Airborne Instrumentation for Astronomy VII , editor =

    Robert Content and Will Saunders and Jon Lawrence and Julia Bryant and Ross Zhelem , title =. Ground-based and Airborne Instrumentation for Astronomy VII , editor =. 2018 , doi =

    2018

  27. [27]

    Ground-based and Airborne Instrumentation for Astronomy IX , editor =

    Ross Zhelem and Julia Bryant and Joss Bland-Hawthorn and Rebecca Brown and Robert Content and Scott Croom and Tony Farrell and Michael Goodwin and Ellen Houston and Urs Klauser and Jon Lawrence and Slavko Mali and Rolf Muller and Richard Mcdermid and Helen McGregor and Mahesh Mohanan and Barnaby Norris and Naveen Pai and David Robertson and Will Saunders ...

    2022

  28. [28]

    Dark Matter Contraction and the Stellar Content of Massive Early-type Galaxies: Disfavoring "Light" Initial Mass Functions

    Dark Matter Contraction and the Stellar Content of Massive Early-type Galaxies: Disfavoring ``Light'' Initial Mass Functions. , keywords =. doi:10.1088/2041-8205/721/2/L163 , archivePrefix =. 1007.2409 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1088/2041-8205/721/2/l163 2041

  29. [29]

    AN OBJECTIVE DEFINITION FOR THE MAIN SEQUENCE OF STAR-FORMING GALAXIES , volume=

    Renzini, Alvio and Peng, Ying-jie , year=. AN OBJECTIVE DEFINITION FOR THE MAIN SEQUENCE OF STAR-FORMING GALAXIES , volume=. The Astrophysical Journal , publisher=. doi:10.1088/2041-8205/801/2/l29 , number=

    work page doi:10.1088/2041-8205/801/2/l29 2041

  30. [30]

    On the Nature of Sodium Excess Objects. I. Data and Observed Trends. , keywords =. doi:10.1088/0067-0049/208/1/7 , archivePrefix =. 1307.1472 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1088/0067-0049/208/1/7

  31. [31]

    , keywords =

    Stellar population models of Lick indices with variable element abundance ratios. , keywords =. doi:10.1046/j.1365-8711.2003.06248.x , archivePrefix =. astro-ph/0209250 , primaryClass =

    work page doi:10.1046/j.1365-8711.2003.06248.x 2003

  32. [32]

    Old Stellar Populations. V. Absorption Feature Indices for the Complete Lick/IDS Sample of Stars. , keywords =. doi:10.1086/192087 , adsurl =

    work page doi:10.1086/192087

  33. [33]

    Evidence For A Mild Steepening And Bottom-Heavy IMF In Massive Galaxies From Sodium And Titanium-Oxide Indicators

    Evidence for a Mild Steepening and Bottom-heavy Initial Mass Function in Massive Galaxies from Sodium and Titanium-oxide Indicators. , keywords =. doi:10.1088/2041-8205/753/2/L32 , archivePrefix =. 1204.3823 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1088/2041-8205/753/2/l32 2041

  34. [34]

    The Initial Mass Function of Stars: Evidence for Uniformity in Variable Systems

    The Initial Mass Function of Stars: Evidence for Uniformity in Variable Systems. Science , keywords =. doi:10.1126/science.1067524 , archivePrefix =. astro-ph/0201098 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1126/science.1067524

  35. [35]

    The SAMI Galaxy Survey: Data Release Two with absorption-line physics value-added products

    The SAMI Galaxy Survey: Data Release Two with absorption-line physics value-added products. , keywords =. doi:10.1093/mnras/sty2355 , archivePrefix =. 1808.03365 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/sty2355

  36. [36]

    Performance of AAOmega: the AAT multi-purpose fiber-fed spectrograph , volume=

    Sharp, Robert and Saunders, Will and Smith, Greg and Churilov, Vladimir and Correll, David and Dawson, John and Farrel, Tony and Frost, Gabriella and Haynes, Roger and Heald, Ron and Lankshear, Allan and Mayfield, Don and Waller, Lew and Whittard, Dennis , editor=. Performance of AAOmega: the AAT multi-purpose fiber-fed spectrograph , volume=. 2006 , mont...

    work page doi:10.1117/12.671022 2006

  37. [37]

    , keywords =

    Focal ratio degradation in optical fibres for the Hector integral field units. , keywords =. doi:10.1093/mnras/stad1273 , adsurl =

    work page doi:10.1093/mnras/stad1273

  38. [38]

    Ground-based and Airborne Instrumentation for Astronomy VIII , year = 2020, editor =

    The Hector Instrument: performance of the Hector fibre integral field units. Ground-based and Airborne Instrumentation for Astronomy VIII , year = 2020, editor =. doi:10.1117/12.2561514 , adsurl =

    work page doi:10.1117/12.2561514 2020

  39. [39]

    UV/Optical/IR Space Telescopes and Instruments: Innovative Technologies and Concepts IX , year = 2019, editor =

    Development and focal ratio degradation optimisation of integral field units on Hector. UV/Optical/IR Space Telescopes and Instruments: Innovative Technologies and Concepts IX , year = 2019, editor =. doi:10.1117/12.2529212 , adsurl =

    work page doi:10.1117/12.2529212 2019

  40. [40]

    Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation III , year = 2018, editor =

    New-generation hexabundles: development and initial results. Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation III , year = 2018, editor =. doi:10.1117/12.2313033 , adsurl =

    work page doi:10.1117/12.2313033 2018

  41. [41]

    Focal ratio degradation in lightly-fused hexabundles

    Focal ratio degradation in lightly fused hexabundles. , keywords =. doi:10.1093/mnras/stt2254 , archivePrefix =. 1311.6865 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/stt2254

  42. [43]

    Ground-based and Airborne Instrumentation for Astronomy X , year = 2024, editor =

    Hector: performance of the new integral field spectrograph instrument for the Anglo-Australian Telescope. Ground-based and Airborne Instrumentation for Astronomy X , year = 2024, editor =. doi:10.1117/12.3016340 , adsurl =

    work page doi:10.1117/12.3016340 2024

  43. [44]

    The galaxy-wide IMF of dwarf late-type to massive early-type galaxies

    The galaxy-wide initial mass function of dwarf late-type to massive early-type galaxies. , keywords =. doi:10.1093/mnras/stt1806 , archivePrefix =. 1309.6634 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/stt1806

  44. [45]

    Counting Low-Mass Stars in Integrated Light

    Counting Low-mass Stars in Integrated Light. , keywords =. doi:10.1088/0004-637X/747/1/69 , archivePrefix =. 1109.0007 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1088/0004-637x/747/1/69

  45. [46]

    The SAMI Galaxy Survey: Revisiting Galaxy Classification Through High-Order Stellar Kinematics

    The SAMI Galaxy Survey: Revisiting Galaxy Classification through High-order Stellar Kinematics. , keywords =. doi:10.3847/1538-4357/835/1/104 , archivePrefix =. 1611.07039 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/1538-4357/835/1/104

  46. [47]

    Chen, Yan-Ping and Trager, S. C. and Peletier, R. F. and Lançon, A. and Vazdekis, A. and Prugniel, Ph. and Silva, D. R. and Gonneau, A. , year=. The X-shooter Spectral Library (XSL): I. DR1: Near-ultraviolet through optical spectra from the first year of the survey⋆ , volume=. doi:10.1051/0004-6361/201322505 , journal=

    work page doi:10.1051/0004-6361/201322505

  47. [48]

    , keywords =

    Classification parameters for the emission-line spectra of extragalactic objects. , keywords =. doi:10.1086/130766 , adsurl =

    work page doi:10.1086/130766

  48. [49]

    , keywords =

    Variation of the High-mass Slope of the Stellar Initial Mass Function: Theory Meets Observations. , keywords =. doi:10.3847/1538-4357/ad09bc , archivePrefix =. 2309.10842 , primaryClass =

    work page doi:10.3847/1538-4357/ad09bc

  49. [50]

    emcee: The MCMC Hammer

    emcee: The MCMC Hammer. , keywords =. doi:10.1086/670067 , archivePrefix =. 1202.3665 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1086/670067

  50. [51]

    , keywords =

    The ages and metallicities of galaxies in the local universe. , keywords =. doi:10.1111/j.1365-2966.2005.09321.x , archivePrefix =. astro-ph/0506539 , primaryClass =

    work page doi:10.1111/j.1365-2966.2005.09321.x 2005

  51. [52]

    , keywords =

    Semi-empirical analysis of Sloan Digital Sky Survey galaxies - I. Spectral synthesis method. , keywords =. doi:10.1111/j.1365-2966.2005.08752.x , archivePrefix =. astro-ph/0412481 , primaryClass =

    work page doi:10.1111/j.1365-2966.2005.08752.x 2005

  52. [53]

    Improving the full spectrum fitting method: accurate convolution with Gauss-Hermite functions

    Improving the full spectrum fitting method: accurate convolution with Gauss-Hermite functions. , keywords =. doi:10.1093/mnras/stw3020 , archivePrefix =. 1607.08538 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/stw3020

  53. [54]

    , keywords =

    Full spectrum fitting with photometry in PPXF: stellar population versus dynamical masses, non-parametric star formation history and metallicity for 3200 LEGA-C galaxies at redshift z 0.8. , keywords =. doi:10.1093/mnras/stad2597 , archivePrefix =. 2208.14974 , primaryClass =

    work page doi:10.1093/mnras/stad2597

  54. [55]

    , eprint =

    Parametric Recovery of Line-of-Sight Velocity Distributions from Absorption-Line Spectra of Galaxies via Penalized Likelihood. , keywords =. doi:10.1086/381875 , archivePrefix =. astro-ph/0312201 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1086/381875

  55. [56]

    , keywords =

    Theoretical isochrones from models with new radiative opacities. , keywords =

  56. [57]

    A library of high resolution synthetic stellar spectra from 300nm to 1.8 micron with solar and alpha-enhanced composition

    A library of high resolution synthetic stellar spectra from 300 nm to 1.8 m with solar and -enhanced composition. , keywords =. doi:10.1051/0004-6361:20053511 , archivePrefix =. astro-ph/0505511 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1051/0004-6361:20053511

  57. [58]

    VizieR Online Data Catalog: MILES library of empirical spectra (Sanchez-blazquez+, 2006)

    2006

  58. [59]

    A Large Stellar Evolution Database for Population Synthesis Studies. II. Stellar Models and Isochrones for an -enhanced Metal Distribution. , keywords =. doi:10.1086/501344 , archivePrefix =. astro-ph/0603721 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1086/501344

  59. [60]

    A Large Stellar Evolution Database for Population Synthesis Studies. I. Scaled Solar Models and Isochrones. , keywords =. doi:10.1086/422498 , archivePrefix =. astro-ph/0405193 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1086/422498

  60. [61]

    Young LMC clusters: the role of red supergiants and multiple stellar populations in their integrated light and CMDs

    Young LMC clusters: the role of red supergiants and multiple stellar populations in their integrated light and CMDs. , keywords =. doi:10.1093/mnras/stx1824 , archivePrefix =. 1708.00369 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/stx1824

  61. [62]

    Evolutionary stellar population synthesis with MILES - II. Scaled-solar and \alpha-enhanced models

    Evolutionary stellar population synthesis with MILES - II. Scaled-solar and -enhanced models. , keywords =. doi:10.1093/mnras/stv151 , archivePrefix =. 1504.08032 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/stv151

  62. [63]

    , keywords =

    Evolutionary stellar population synthesis with MILES - I. The base models and a new line index system. , keywords =. doi:10.1111/j.1365-2966.2010.16407.x , archivePrefix =. 1004.4439 , primaryClass =

    work page doi:10.1111/j.1365-2966.2010.16407.x 2010

  63. [65]

    , archivePrefix = "arXiv", eprint =

    Galaxy And Mass Assembly (GAMA): stellar mass estimates. , keywords =. doi:10.1111/j.1365-2966.2011.19536.x , archivePrefix =. 1108.0635 , primaryClass =

    work page doi:10.1111/j.1365-2966.2011.19536.x 2011

  64. [66]

    , keywords =

    The effect of the environment-dependent stellar initial mass function on the photometric properties of star-forming galaxies. , keywords =. doi:10.1051/0004-6361/202347928 , archivePrefix =. 2405.05313 , primaryClass =

    work page doi:10.1051/0004-6361/202347928

  65. [67]

    , keywords =

    The SAMI Galaxy Survey: _ SFR drives the presence of complex emission-line profiles in star-forming galaxies. , keywords =. doi:10.1093/mnras/stad3747 , archivePrefix =. 2312.03659 , primaryClass =

    work page doi:10.1093/mnras/stad3747

  66. [68]

    2018 , publisher =

    Dahlgren, Björn , title =. 2018 , publisher =. doi:10.21105/joss.00565 , url =

    work page doi:10.21105/joss.00565 2018

  67. [69]

    , keywords =

    Stellar population synthesis at the resolution of 2003. , keywords =. doi:10.1046/j.1365-8711.2003.06897.x , archivePrefix =. astro-ph/0309134 , primaryClass =

    work page doi:10.1046/j.1365-8711.2003.06897.x 2003

  68. [70]

    SPIDER VIII - Constraints on the Stellar Initial Mass Function of Early-type Galaxies from a Variety of Spectral Features

    SPIDER VIII - constraints on the stellar initial mass function of early-type galaxies from a variety of spectral features. , keywords =. doi:10.1093/mnras/stt943 , archivePrefix =. 1305.2273 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/stt943

  69. [71]

    and Conroy, Charlie , year=

    van Dokkum, Pieter G. and Conroy, Charlie , year=. THE STELLAR INITIAL MASS FUNCTION IN EARLY-TYPE GALAXIES FROM ABSORPTION LINE SPECTROSCOPY. I. DATA AND EMPIRICAL TRENDS , volume=. The Astrophysical Journal , publisher=. doi:10.1088/0004-637x/760/1/70 , number=

    work page doi:10.1088/0004-637x/760/1/70

  70. [72]

    2024 , eprint=

    First detection of CO isotopologues in a high-redshift main-sequence galaxy: evidence of a top-heavy stellar initial mass function , author=. 2024 , eprint=

    2024

  71. [73]

    Extreme CO Isotopic Abundances in the ULIRG IRAS 13120-5453: An Extremely Young Starburst or Top-Heavy Initial Mass Function

    Extreme CO Isotopic Abundances in the ULIRG IRAS 13120-5453: An Extremely Young Starburst or Top-heavy Initial Mass Function. , keywords =. doi:10.3847/2041-8213/aa6ea4 , archivePrefix =. 1704.06671 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.3847/2041-8213/aa6ea4 2041

  72. [74]

    , keywords =

    The evolution of CNO isotopes: the impact of massive stellar rotators. , keywords =. doi:10.1093/mnras/stz2741 , archivePrefix =. 1907.09476 , primaryClass =

    work page doi:10.1093/mnras/stz2741 1907

  73. [75]

    , keywords =

    Star Formation in R136: A Cluster of O3 Stars Revealed by Hubble Space Telescope Spectroscopy. , keywords =. doi:10.1086/305126 , adsurl =

    work page doi:10.1086/305126

  74. [76]

    The Stellar Initial Mass Function (38th Herstmonceux Conference) , year = 1998, editor =

    The Initial Mass Function of Massive Stars in the Local Group. The Stellar Initial Mass Function (38th Herstmonceux Conference) , year = 1998, editor =

    1998

  75. [77]

    The Origin and Universality of the Stellar Initial Mass Function

    The Origin and Universality of the Stellar Initial Mass Function. Protostars and Planets VI , year = 2014, editor =. doi:10.2458/azu_uapress_9780816531240-ch003 , archivePrefix =. 1312.5326 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.2458/azu_uapress_9780816531240-ch003 2014

  76. [78]

    Galactic Stellar and Substellar Initial Mass Function

    Galactic Stellar and Substellar Initial Mass Function. , keywords =. doi:10.1086/376392 , archivePrefix =. astro-ph/0304382 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1086/376392

  77. [79]

    Modeling the Panchromatic Spectral Energy Distributions of Galaxies

    Conroy, Charlie , year=. Modeling the Panchromatic Spectral Energy Distributions of Galaxies , volume=. Annual Review of Astronomy and Astrophysics , publisher=. doi:10.1146/annurev-astro-082812-141017 , number=

    work page internal anchor Pith review doi:10.1146/annurev-astro-082812-141017

  78. [80]

    Fitting the integrated spectral energy distributions of galaxies , volume=

    Walcher, Jakob and Groves, Brent and Budavári, Tamás and Dale, Daniel , year=. Fitting the integrated spectral energy distributions of galaxies , volume=. Astrophysics and Space Science , publisher=. doi:10.1007/s10509-010-0458-z , number=

    work page doi:10.1007/s10509-010-0458-z

  79. [81]

    Multi-Epoch High-Spectral-Resolution Observations of Neutral Sodium in 14 Type Ia Supernovae

    Multi-epoch high-spectral-resolution observations of neutral sodium in 14 Type Ia supernovae. , keywords =. doi:10.1093/mnras/stu1202 , archivePrefix =. 1311.3645 , primaryClass =

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.1093/mnras/stu1202

  80. [82]

    Empirical verification

    Poznanski, Dovi and Prochaska, J. Xavier and Bloom, Joshua S. , year=. An empirical relation between sodium absorption and dust extinction: Sodium and dust , volume=. Monthly Notices of the Royal Astronomical Society , publisher=. doi:10.1111/j.1365-2966.2012.21796.x , number=

    work page doi:10.1111/j.1365-2966.2012.21796.x 2012

Showing first 80 references.