# Traces of Galaxy Formation: Stellar populations, Dynamics and Morphology

Start year
2006
Organizational Unit
Organizing institutions

### Grants related:

General
Description

#### Welcome to the Traces of Galaxy Formation research group website.

We are a large, diverse, and very active research group aiming to provide a comprehensive picture for the formation of galaxies in the Universe. Rooted in detailed stellar population analysis, we are constantly exploring and developing new tools and ideas to understand how galaxies came to be what we now observe.

A complex star formation history, as the one expected to describe galaxy evolution, needs a multidisciplinary approach to be fully understood. Our group at the IAC consists of experienced researchers in cosmological simulations, dynamical studies, stellar populations and morphological properties of galaxies up to high redshift. We combine different approaches (e.g. observations and theory, secular and cosmological evolution studies) to obtain a complete view of the dominant mechanisms driving the evolution of galaxies.

Within this general framework, we are currently exploring three main areas of research:

1. Stellar population synthesis models
• Development of new stellar population synthesis models
• Stellar population analysis tools
• Universality of the stellar initial mass function (IMF)

2. Cosmic evolution of galaxies
• Massive galaxy evolution
• Stellar populations in different environments
• Low surface brightness science
• Machine learning and cosmological simulations

3. Evolutionary processes in nearby galaxies
• The role of black holes in the evolution of galaxies
• Surveys of nearby galaxies
• Stellar kinematics and dynamical models

If you want to get in contact or work with us, please send an email to the head of the group (Ignacio Martín-Navarro ignacio.martin [at] iac.es).

Here you can find some of our most recent highlights:

### Related publications

• Introducing the LBT Imaging of Galactic Halos and Tidal Structures (LIGHTS) survey. A preview of the low surface brightness Universe to be unveiled by LSST

We present the first results of the LBT Imaging of Galaxy Haloes and Tidal Structures (LIGHTS) survey. LIGHTS is an ongoing observational campaign with the 2 × 8.4 m Large Binocular Telescope (LBT) aiming to explore the stellar haloes and the low surface brightness population of satellites down to a depth of μV ∼ 31 mag arcsec−2 (3σ in 10″ × 10″

Trujillo, Ignacio et al.

10
2021
• A Disk and No Signatures of Tidal Distortion in the Galaxy "Lacking" Dark Matter NGC 1052-DF2

Using ultra-deep imaging (μg = 30.4 mag arcsec-2; 3σ, 10″ × 10″), we probed the surroundings of the first galaxy "lacking" dark matter (DM) KKS2000[04] (NGC 1052-DF2). Signs of tidal stripping in this galaxy would explain its claimed low content of DM. However, we find no evidence of tidal tails. In fact, the galaxy remains undisturbed down to a

Montes, Mireia et al.

9
2021
• Surface brightness fluctuations to constrain secondary stellar populations: revealing very low-metallicity stars in massive galaxies

The aim of this work is to explore the potential of surface brightness fluctuations (SBF) for studying composite stellar populations (CSP). To do so, we have computed the standard (mean) and SBF spectra with E-MILES stellar population synthesis code. We have created a set of models composed by different mass fractions of two single stellar

Rodríguez-Beltrán, P. et al.

10
2021
• The miniJPAS survey: A preview of the Universe in 56 colors

The Javalambre-Physics of the Accelerating Universe Astrophysical Survey (J-PAS) will scan thousands of square degrees of the northern sky with a unique set of 56 filters using the dedicated 2.55 m Javalambre Survey Telescope (JST) at the Javalambre Astrophysical Observatory. Prior to the installation of the main camera (4.2 deg2 field-of-view with

Bonoli, S. et al.

9
2021
• The Fornax 3D project: PNe populations and stellar metallicity in edge-on galaxies

Context. Extragalactic planetary nebulae (PNe) are useful distance indicators and are often used to trace the dark-matter content in external galaxies. At the same time, PNe can also be used as probes of their host galaxy stellar populations and to help understand the later stages of stellar evolution. Previous works have indicated that a specific

Galán-de Anta, P. M. et al.

8
2021
• The lens SW05 J143454.4+522850: a fossil group at redshift 0.6?

Fossil groups are considered the end product of natural galaxy group evolution in which group members sink towards the centre of the gravitational potential due to dynamical friction, merging into a single, massive, and X-ray bright elliptical. Since gravitational lensing depends on the mass of a foreground object, its mass concentration, and

Denzel, Philipp et al.

9
2021
• Local variations of the Stellar Velocity Ellipsoid-I: the disc of galaxies in the Auriga simulations

The connection between the Stellar Velocity Ellipsoid (SVE) and the dynamical evolution of galaxies has been a matter of debate in the last years and there is no clear consensus whether different heating agents (e.g. spiral arms, giant molecular clouds, bars and mergers) leave clear detectable signatures in the present day kinematics. Most of these

Walo-Martín, Daniel et al.

9
2021
• Pushing automated morphological classifications to their limits with the Dark Energy Survey

We present morphological classifications of ~27 million galaxies from the Dark Energy Survey (DES) Data Release 1 (DR1) using a supervised deep learning algorithm. The classification scheme separates: (a) early-type galaxies (ETGs) from late-type galaxies (LTGs); and (b) face-on galaxies from edge-on. Our convolutional neural networks (CNNs) are

Vega-Ferrero, J. et al.

9
2021
• The ultraviolet luminosity function of star-forming galaxies between redshifts of 0.6 and 1.2

We use ultraviolet (UV) imaging taken with the XMM-Newton Optical Monitor telescope (XMM-OM), covering 280 arcmin2 in the UVW1 band (λeff = 2910 Å) to measure rest-frame UV 1500-Å luminosity functions of galaxies with redshifts z between 0.6 and 1.2. The XMM-OM data are supplemented by a large body of optical and infrared imaging to provide

Page, M. J. et al.

9
2021
• Extending the evolution of the stellar mass-size relation at z ≤ 2 to low stellar mass galaxies from HFF and CANDELS

We reliably extend the stellar mass-size relation over 0.2 ≤ z ≤ 2 to low stellar mass galaxies by combining the depth of Hubble Frontier Fields with the large volume covered by CANDELS. Galaxies are simultaneously modelled in multiple bands using the tools developed by the MegaMorph project, allowing robust size (i.e. half-light radius) estimates

Nedkova, Kalina V. et al.

9
2021
• The size function of massive satellites from the R<SUB>e</SUB>-R<SUB>h</SUB> and M<SUB>star</SUB>-M<SUB>h</SUB> relations: constraining the role of environment

In previous work, we showed that a semi-empirical model in which galaxies in host dark matter haloes are assigned stellar masses via a stellar mass-halo mass (SMHM) relation and sizes (Re) via a linear and tight Re-Rh relation can faithfully reproduce the size function of local Sloan Digital Sky Survey (SDSS) central galaxies and the strong size

Zanisi, L. et al.

7
2021
• Constraints on the dust extinction law of the Galaxy with Swift/UVOT, Gaia, and 2MASS

We explore variations of the dust extinction law of the Milky Way by selecting stars from the Swift/UVOT Serendipitous Source Catalogue, cross-matched with Gaia DR2 and 2MASS to produce a sample of 10 452 stars out to ~4 kpc with photometry covering a wide spectral window. The near ultraviolet passbands optimally encompass the 2175 Å bump, so that

Ferreras, Ignacio et al.

7
2021
• The SAMI Galaxy Survey: the third and final data release

We have entered a new era where integral-field spectroscopic surveys of galaxies are sufficiently large to adequately sample large-scale structure over a cosmologically significant volume. This was the primary design goal of the SAMI Galaxy Survey. Here, in Data Release 3, we release data for the full sample of 3068 unique galaxies observed. This

Croom, Scott M. et al.

7
2021
• Mild radial variations of the stellar IMF in the bulge of M31

Using new, homogeneous, long-slit spectroscopy in the wavelength range from ~0.35 to $\sim 1 \, \mu$m, we study radial gradients of optical and near-infrared (NIR) initial mass function (IMF)-sensitive features along the major axis of the bulge of M31, out to a galactocentric distance of ~200 arcsec (~800 pc). Based on state-of-the-art stellar

La Barbera, F. et al.

7
2021
• Anisotropic satellite galaxy quenching modulated by black hole activity

The evolution of satellite galaxies is shaped by their constant interaction with the circumgalactic medium surrounding central galaxies, which in turn may be affected by gas and energy ejected from the central supermassive black hole1-6. The nature of such a coupling between black holes and galaxies is, however, much debated7-9 and observational

Martín-Navarro, Ignacio et al.

0
2021
• The evolution of compact massive quiescent and star-forming galaxies derived from the R<SUB>e</SUB>-R<SUB>h</SUB> and M<SUB>star</SUB>-M<SUB>h</SUB> relations

The mean size (effective radius Re) of massive galaxies (MGs; Mstar > 1011.2M⊙) is observed to increase steadily with cosmic time. It is still unclear whether this trend originates from the size growth of individual galaxies (via, e.g. mergers and/or AGN feedback) or from the inclusion of larger galaxies entering the selection at later epochs

Zanisi, L. et al.

8
2021
• Diversity of nuclear star cluster formation mechanisms revealed by their star formation histories

Nuclear star clusters (NSCs) are the densest stellar systems in the Universe and are found in the centres of all types of galaxies. They are thought to form via mergers of star clusters such as ancient globular clusters (GCs) that spiral to the centre as a result of dynamical friction or through in situ star formation directly at the galaxy centre

Fahrion, K. et al.

6
2021
• History of the gas fuelling star formation in EAGLE galaxies

Theory predicts that cosmological gas accretion plays a fundamental role fuelling star formation in galaxies. However, a detailed description of the accretion process to be used when interpreting observations is still lacking. Using the state-of-the-art cosmological hydrodynamical simulation EAGLE, we work out the chemical inhomogeneities arising

Scholz-Díaz, Laura et al.

8
2021
• An extension of the MILES library with derived T<SUB>eff</SUB>, log g, [Fe/H], and [α/Fe]

Extragalactic astronomy and stellar astrophysics are intrinsically related. In fact, the determination of important galaxy properties such as stellar masses, star formation histories, or chemical abundances relies on the ability to model their stellar populations. One important ingredient of these models is stellar libraries. Empirical libraries

García Pérez, A. E. et al.

8
2021
• A Duality in the Origin of Bulges and Spheroidal Galaxies

Studying the resolved stellar populations of the different structural components that build massive galaxies directly unveils their assembly history. We aim at characterizing the stellar population properties of a representative sample of bulges and pure spheroids in massive galaxies (M⋆ > 1010 M⊙) in the GOODS-N field. We take advantage of the

Costantin, Luca et al.