Traces of Galaxy Formation: Stellar populations, Dynamics and Morphology

    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 (ignacio[dot]martin[at]iac[dot]es)).

    Principal investigator

    Here you can find some of our most recent highlights:

    Related publications

    • NGC 1277: A Massive Compact Relic Galaxy in the Nearby Universe
      As early as 10 Gyr ago, galaxies with more than 1011 M ☉ of stars already existed. While most of these massive galaxies must have subsequently transformed through on-going star formation and mergers with other galaxies, a small fraction (lsim0.1%) may have survived untouched until today. Searches for such relic galaxies, useful windows to explore
      Vazdekis, A. et al.

      Advertised on:

      1
      2014
      Citations
      110
    • The galaxy-wide initial mass function of dwarf late-type to massive early-type galaxies
      Observational studies are showing that the galaxy-wide stellar initial mass function (IMF) is top-heavy in galaxies with high star formation rates (SFRs). Calculating the integrated galactic stellar initial mass function (IGIMF) as a function of the SFR of a galaxy, it follows that galaxies which have or which formed with SFRs >10 M⊙ yr-1 would
      Weidner, C. et al.

      Advertised on:

      12
      2013
      Citations
      86
    • Fully cosmological virtual massive galaxies at z = 0: kinematical, morphological and stellar population characterization
      We present the results of a numerical adaptive mesh refinement hydrodynamical and N-body simulation in a Λ cold dark matter cosmology. We focus on the analysis of the main properties of massive galaxies (M* > 1011 M⊙) at z = 0. For all the massive virtual galaxies, we carry out a careful study of their one-dimensional density, luminosity, velocity
      Vazdekis, A. et al.

      Advertised on:

      12
      2013
      Citations
      39
    • The O3N2 and N2 abundance indicators revisited: improved calibrations based on CALIFA and Te-based literature data
      The use of integral field spectroscopy is since recently allowing to measure the emission line fluxes of an increasingly large number of star-forming galaxies, both locally and at high redshift. Many studies have used these fluxes to derive the gas-phase metallicity of the galaxies by applying the so-called strong-line methods. However, the
      Marino, R. A. et al.

      Advertised on:

      11
      2013
      Citations
      492
    • The (galaxy-wide) IMF in giant elliptical galaxies: from top to bottom
      Recent evidence based independently on spectral line strengths and dynamical modelling point towards a non-universal stellar initial mass function (IMF), probably implying an excess of low-mass stars in elliptical galaxies with a high velocity dispersion. Here, we show that a time-independent bottom-heavy IMF is compatible neither with the observed
      Weidner, C. et al.

      Advertised on:

      11
      2013
      Citations
      79
    • The nature of LINER galaxies:. Ubiquitous hot old stars and rare accreting black holes
      Context. Galaxies, which often contain ionised gas, sometimes also exhibit a so-called low-ionisation nuclear emission line region (LINER). For 30 years, this was attributed to a central mass-accreting supermassive black hole (more commonly known as active galactic nucleus, AGN) of low luminosity, making LINER galaxies the largest AGN sub
      Singh, R. et al.

      Advertised on:

      10
      2013
      Citations
      260
    • Tests of model predictions for the responses of stellar spectra and absorption-line indices to element abundance variations
      A method that is widely used to analyse stellar populations in galaxies is to apply the theoretically derived responses of stellar spectra and line indices to element abundance variations, which are hereafter referred to as response functions. These are applied in a differential way, to base models, in order to generate spectra or indices with
      Sánchez-Blázquez, P. et al.

      Advertised on:

      10
      2013
      Citations
      25
    • Resolving galaxies in time and space. I. Applying STARLIGHT to CALIFA datacubes
      Aims: Fossil record methods based on spectral synthesis techniques have matured during the past decade, and their application to integrated galaxy spectra has fostered substantial advances in the understanding of galaxies and their evolution. Yet, because of the lack of spatial resolution, these studies are limited to a global view, providing no
      Cid Fernandes, R. et al.

      Advertised on:

      9
      2013
      Citations
      190
    • Bottom-heavy initial mass function in a nearby compact L★ galaxy
      We present orbit-based dynamical models and stellar population analysis of Sloan Digital Sky Survey J151741.75-004217.6, a low-redshift (z = 0.116) early-type galaxy (ETG) which, for its moderate luminosity, has an exceptionally high velocity dispersion. We aim to determine the central black hole (BH) mass (M•), the i-band stellar mass-to-light
      Läsker, R. et al.

      Advertised on:

      7
      2013
      Citations
      41
    • SPIDER VIII - constraints on the stellar initial mass function of early-type galaxies from a variety of spectral features
      We perform a spectroscopic study to constrain the stellar initial mass function (IMF) by using a large sample of 24 781 early-type galaxies from the Sloan Digital Sky Survey-based Spheroids Panchromatic Investigation in Different Environmental Regions survey. Clear evidence is found of a trend between IMF and central velocity dispersion (σ0)
      La Barbera, F. et al.

      Advertised on:

      8
      2013
      Citations
      248
    • The mmax-Mecl relation, the IMF and IGIMF: probabilistically sampled functions
      We introduce a new method to measure the dispersion of mmax values of star clusters and show that the observed sample of mmax is inconsistent with random sampling from a universal stellar initial mass function (IMF) at a 99.9 per cent confidence level. The scatter seen in the mmax-Mecl data can be mainly (76 per cent) understood as being the result
      Weidner, C. et al.

      Advertised on:

      9
      2013
      Citations
      90
    • Expected Number of Massive Galaxy Relics in the Present Day Universe
      The number of present day massive galaxies that have survived untouched since their formation at high-z is an important observational constraint to the hierarchical galaxy formation models. Using three different semianalytical models based on the Millenium simulation, we quantify the expected fraction and number densities of the massive galaxies
      Trujillo, I. et al.

      Advertised on:

      8
      2013
      Citations
      45
    • The merger history of massive spheroids since z ˜ 1 is size-independent
      Using a compilation of 379 massive (stellar mass M ≳ 1011 M⊙) spheroid-like galaxies from the near-infrared Palomar/DEEP-2 survey, we investigated, up to z ˜ 1, whether the presence of companions depends on the size of the host galaxy. We explored the presence of companions for mass ratios with respect to the central massive galaxy down to 1 : 10
      Díaz-García, L. A. et al.

      Advertised on:

      7
      2013
      Citations
      6
    • Nebular emission and the Lyman continuum photon escape fraction in CALIFA early-type galaxies
      We use deep integral field spectroscopy data from the CALIFA survey to study the warm interstellar medium (wim) over the entire extent and optical spectral range of 32 nearby early-type galaxies (ETGs). We find that faint nebular emission is extended in all cases, and its surface brightness decreases roughly as ∝ r-α. The large standard deviation
      Papaderos, P. et al.

      Advertised on:

      7
      2013
      Citations
      99
    • The ATLAS3D project - XXII. Low-efficiency star formation in early-type galaxies: hydrodynamic models and observations
      We study the global efficiency of star formation in high-resolution hydrodynamical simulations of gas discs embedded in isolated early-type and spiral galaxies. Despite using a universal local law to form stars in the simulations, we find that the early-type galaxies are offset from the spirals on the large-scale Kennicutt relation, and form stars
      Martig, Marie et al.

      Advertised on:

      7
      2013
      Citations
      106
    • Aperture corrections for disk galaxy properties derived from the CALIFA survey. Balmer emission lines in spiral galaxies
      This work investigates the effect of the aperture size on derived galaxy properties for which we have spatially-resolved optical spectra. We focus on some indicators of star formation activity and dust attenuation for spiral galaxies that have been widely used in previous work on galaxy evolution. We investigated 104 spiral galaxies from the CALIFA
      Iglesias-Páramo, J. et al.

      Advertised on:

      5
      2013
      Citations
      40
    • An Integral View of Fast Shocks Around Supernova 1006
      Supernova remnants are among the most spectacular examples of astrophysical pistons in our cosmic neighborhood. The gas expelled by the supernova explosion is launched with velocities ∼1000 kilometers per second into the ambient, tenuous interstellar medium, producing shocks that excite hydrogen lines. We have used an optical integral-field
      Nikolić, Sladjana et al.

      Advertised on:

      4
      2013
      Citations
      39
    • Distinct stellar populations in the inner bars of double-barred galaxies
      Numerical simulations of double-barred galaxies predict the build-up of different structural components (e.g. bulges, inner discs) in the central regions of disc galaxies. In those simulations, inner bars have a prominent role in the internal secular evolution of their host galaxies. The development of bulges and inner discs is, however, poorly
      de Lorenzo-Cáceres, A. et al.

      Advertised on:

      5
      2013
      Citations
      34
    • Stellar haloes of disc galaxies at z ˜ 1
      Taking advantage of the ultradeep near-infrared imaging obtained with the Hubble Space Telescope on the Hubble Ultra Deep Field, we detect and explore for the first time the properties of the stellar haloes of two Milky Way-like galaxies at z ˜ 1. We find that the structural properties of those haloes (size and shape) are similar to the ones found
      Trujillo, I. et al.

      Advertised on:

      5
      2013
      Citations
      32
    • The impact of a non-universal Initial Mass Function on the star formation histories of early-type galaxies
      Recent results on the non-universality of the Initial Mass Function (IMF) have shown strong evidence of IMF variations with galaxy velocity dispersion, with a corresponding impact on other stellar population parameters, line indices and colours. Using a set of stellar population models with varying IMF slopes, we provide additional caveats on the
      de la Rosa, I. G. et al.

      Advertised on:

      5
      2013
      Citations
      34

    Related talks

    No related talks were found.

    Related conferences

    No related conferences were found.
    Type
    State