Dwarf Galaxies in the MATLAS Survey: Hubble Space Telescope Observations of the Globular Cluster System in the Ultra-diffuse Galaxy MATLAS-2019

Abstract Ultra-diffuse galaxies (UDGs) are very-low-surface-brightness galaxies with large effective radii. Spectroscopic measurements of a few UDGs have revealed a low dark-matter content based on the internal motion of stars or globular clusters (GCs). This is in contrast to the large number of GCs found for these systems, from which it would be expected to correspond to a large dark-matter halo mass. Here we present HST+ACS observations for the UDG MATLAS-2019 in the NGC 5846 group. Using the F606W and F814W filters, we trace the GC population two magnitudes below the peak of the GC luminosity function (GCLF). Employing Bayesian considerations, we identify 26 ± 6 GCs associated with the dwarf, yielding a large specific frequency of S N = 58 ± 14. We use the turnover of the GCLF to derive a distance of 21 ± 2 Mpc, which is consistent with the NGC 5846 group of galaxies. Due to the superior image quality of the HST, we are able to resolve the GCs and measure their sizes, which are consistent with the sizes of GCs around Local Group galaxies. Using the linear relation between the total mass of galaxies and of GCs, we derive a halo mass of 0.9 ± 0.2 × 1011 M ⊙ (M ⊙/L ⊙ > 1000). The high abundance of GCs, together with the small uncertainties, make MATLAS-2019 one of the most extreme UDGs, which likely sets an upper limit of the number of GCs for UDGs.

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Massive low-surface-brightness galaxies in the eagle simulation

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1798 ◽

2020 ◽

Vol 496 (3) ◽

pp. 3996-4016

Author(s):

Andrea Kulier ◽

Gaspar Galaz ◽

Nelson D Padilla ◽

James W Trayford

Keyword(s):

Dark Matter ◽

Angular Momentum ◽

Surface Density ◽

Surface Brightness ◽

Initial Conditions ◽

High Surface ◽

Formation Rate ◽

Dark Matter Halo ◽

Low Surface Brightness ◽

Low Surface Brightness Galaxies

ABSTRACT We investigate the formation and properties of low surface brightness galaxies (LSBGs) with M* > 109.5 M⊙ in the eagle hydrodynamical cosmological simulation. Galaxy surface brightness depends on a combination of stellar mass surface density and mass-to-light ratio (M/L), such that low surface brightness is strongly correlated with both galaxy angular momentum (low surface density) and low specific star formation rate (high M/L). This drives most of the other observed correlations between surface brightness and galaxy properties, such as the fact that most LSBGs have low metallicity. We find that LSBGs are more isolated than high-surface-brightness galaxies (HSBGs), in agreement with observations, but that this trend is driven entirely by the fact that LSBGs are unlikely to be close-in satellites. The majority of LSBGs are consistent with a formation scenario in which the galaxies with the highest angular momentum are those that formed most of their stars recently from a gas reservoir co-rotating with a high-spin dark matter halo. However, the most extended LSBG discs in EAGLE, which are comparable in size to observed giant LSBGs, are built up via mergers. These galaxies are found to inhabit dark matter haloes with a higher spin in their inner regions (<0.1r200c), even when excluding the effects of baryonic physics by considering matching haloes from a dark-matter-only simulation with identical initial conditions.

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Observational insights on the origin of giant low surface brightness galaxies

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab374 ◽

2021 ◽

Vol 503 (1) ◽

pp. 830-849

Author(s):

Anna S Saburova ◽

Igor V Chilingarian ◽

Anastasia V Kasparova ◽

Olga K Sil’chenko ◽

Kirill A Grishin ◽

...

Keyword(s):

Dark Matter ◽

Galaxy Formation ◽

Surface Brightness ◽

High Surface ◽

Dark Matter Halo ◽

High Mass ◽

Formation Mechanisms ◽

Orbital Parameters ◽

Low Surface Brightness ◽

Low Surface Brightness Galaxies

ABSTRACT Giant low surface brightness galaxies (gLSBGs) with dynamically cold stellar discs reaching the radius of 130 kpc challenge currently considered galaxy formation mechanisms. We analyse new deep long-slit optical spectroscopic observations, archival optical images, and published Hi and optical spectroscopic data for a sample of seven gLSBGs, for which we performed mass modelling and estimated the parameters of dark matter haloes assuming the Burkert dark matter density profile. Our sample is not homogeneous by morphology, parameters of stellar populations, and total mass, however, six of seven galaxies sit on the high-mass extension of the baryonic Tully–Fisher relation. In UGC 1382, we detected a global counterrotation of the stellar high surface brightness (HSB) disc with respect to the extended LSB disc. In UGC 1922 with signatures of a possible merger, the gas counterrotation is seen in the inner disc. Six galaxies host active galactic nuclei, three of which have the estimated black hole masses substantially below those expected for their (pseudo-)bulge properties suggesting poor merger histories. Overall, the morphology, internal dynamics, and low star formation efficiency in the outer discs indicate that the three formation scenarios shape gLSBGs: (i) a two-stage formation when an HSB galaxy is formed first and then grows an LSB disc by accreting gas from an external supply; (ii) an unusual shallow and extended dark matter halo; (iii) a major merger with fine-tuned orbital parameters and morphologies of the merging galaxies.

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A full pipeline for modelling low surface brightness galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319008548 ◽

2019 ◽

Vol 14 (S353) ◽

pp. 279-280

Author(s):

Marius Peper ◽

Boudewijn F. Roukema ◽

Krzysztof Bolejko

Keyword(s):

Dark Matter ◽

Galaxy Formation ◽

Surface Brightness ◽

Dark Matter Halo ◽

Cosmological Simulations ◽

Galaxy Formation And Evolution ◽

Low Surface Brightness ◽

Formation And Evolution ◽

Low Surface Brightness Galaxies

AbstractCosmological simulations are a powerful tool to test various cosmological and galaxy formation scenarios. The discovery of low surface brightness objects has been a challenge for both of these fields. Our work aims to create a fully reproducible pipeline to generate a realistic dark matter halo catalog with corresponding information on galaxy formation and evolution.

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The universal rotation curve of low surface brightness galaxies – IV. The interrelation between dark and luminous matter

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2700 ◽

2019 ◽

Vol 490 (4) ◽

pp. 5451-5477 ◽

Cited By ~ 5

Author(s):

Chiara Di Paolo ◽

Paolo Salucci ◽

Adnan Erkurt

Keyword(s):

Dark Matter ◽

Surface Brightness ◽

Rotation Curve ◽

High Surface ◽

Dark Matter Halo ◽

Rotation Curves ◽

Central Surface ◽

Low Surface Brightness ◽

Low Surface Brightness Galaxies ◽

Lsb Galaxies

ABSTRACT We investigate the properties of the baryonic and the dark matter components in low surface brightness (LSB) disc galaxies, with central surface brightness in the B band $\mu _0 \ge 23 \, \mathrm{mag \, arcsec}^{-2}$. The sample is composed of 72 objects, whose rotation curves show an orderly trend reflecting the idea of a universal rotation curve (URC) similar to that found in the local high surface brightness (HSB) spirals in previous works. This curve relies on the mass modelling of the co-added rotation curves, involving the contribution from an exponential stellar disc and a Burkert cored dark matter halo. We find that the dark matter is dominant especially within the smallest and less luminous LSB galaxies. Dark matter haloes have a central surface density $\Sigma _0 \sim 100 \, \mathrm{M}_{\odot } \, \mathrm{pc}^{-2}$, similar to galaxies of different Hubble types and luminosities. We find various scaling relations among the LSBs structural properties which turn out to be similar but not identical to what has been found in HSB spirals. In addition, the investigation of these objects calls for the introduction of a new luminous parameter, the stellar compactness C* (analogously to a recent work by Karukes & Salucci), alongside the optical radius and the optical velocity in order to reproduce the URC. Furthermore, a mysterious entanglement between the properties of the luminous and the dark matter emerges.

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The first detection of ultra-diffuse galaxies in the Hydra I cluster from the VEGAS survey

Astronomy and Astrophysics ◽

10.1051/0004-6361/202038523 ◽

2020 ◽

Vol 642 ◽

pp. A48

Author(s):

E. Iodice ◽

M. Cantiello ◽

M. Hilker ◽

M. Rejkuba ◽

M. Arnaboldi ◽

...

Keyword(s):

Surface Brightness ◽

Total Population ◽

Matter Content ◽

Early Type ◽

Low Surface Brightness ◽

Colour Distribution ◽

Specific Frequency ◽

Stellar Masses ◽

Low Surface Brightness Galaxies ◽

Early Type Galaxy

In this paper, we report the discovery of 27 low-surface brightness galaxies, of which 12 are candidates for ultra-diffuse galaxies (UDG) in the Hydra I cluster, based on deep observations taken as part of the VST Early-type Galaxy Survey (VEGAS). This first sample of UDG candidates in the Hydra I cluster represents an important step in our project that aims to enlarge the number of confirmed UDGs and, through study of statistically relevant samples, constrain the nature and formation of UDGs. This study presents the main properties of this class of galaxies in the Hydra I cluster. For all UDGs, we analysed the light and colour distribution, and we provide a census of the globular cluster (GC) systems around them. Given the limitations of a reliable GC selection based on two relatively close optical bands only, we find that half of the UDG candidates have a total GC population consistent with zero. Of the other half, two galaxies have a total population larger than zero at 2σ level. We estimate the stellar mass, the total number of GCs, and the GC specific frequency (SN). Most of the candidates span a range of stellar masses of 107 − 108 M⊙. Based on the GC population of these newly discovered UDGs, we conclude that most of these galaxies have a standard or low dark matter content, with a halo mass of ≤1010 M⊙.

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A distance of 13 Mpc resolves the claimed anomalies of the galaxy lacking dark matter

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz771 ◽

2019 ◽

Vol 486 (1) ◽

pp. 1192-1219 ◽

Cited By ~ 47

Author(s):

Ignacio Trujillo ◽

Michael A Beasley ◽

Alejandro Borlaff ◽

Eleazar R Carrasco ◽

Arianna Di Cintio ◽

...

Keyword(s):

Dark Matter ◽

Galaxy Formation ◽

Globular Clusters ◽

Surface Brightness ◽

Careful Analysis ◽

Matter Content ◽

Low Surface Brightness ◽

Normal Distance ◽

The Galaxy ◽

The Uk

Abstract The claimed detection of a diffuse galaxy lacking dark matter represents a possible challenge to our understanding of the properties of these galaxies and galaxy formation in general. The galaxy, already identified in photographic plates taken in the summer of 1976 at the UK 48-in Schmidt telescope, presents normal distance-independent properties (e.g. colour, velocity dispersion of its globular clusters). However, distance-dependent quantities are at odds with those of other similar galaxies, namely the luminosity function and sizes of its globular clusters, mass-to-light ratio, and dark matter content. Here we carry out a careful analysis of all extant data and show that they consistently indicate a much shorter distance (13 Mpc) than previously indicated (20 Mpc). With this revised distance, the galaxy appears to be a rather ordinary low surface brightness galaxy (Re = 1.4 ± 0.1 kpc; M⋆ = 6.0 ± 3.6 × 107 M⊙) with plenty of room for dark matter (the fraction of dark matter inside the half-mass radius is >75 per cent and Mhalo/M⋆>20) corresponding to a minimum halo mass >109 M⊙. At 13 Mpc, the luminosity and structural properties of the globular clusters around the object are the same as those found in other galaxies.

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