Astrofísica Numérica: Formación y Evolución de Galaxias

    General
    Descripción

    Entre las cuestiones fundamentales en Astronomía y Astrofísica están la formación y evolución de galaxias. Las escalas de tiempo y tamaño son tan astronómicas que su observación en galaxias individuales es imposible. Solo con el uso de simulaciones numéricas es posible entender la formación de estructuras cósmicas dentro del actual marco cosmológico.

    Los principales procesos físicos que rigen la formación y evolución de galaxias son gravedad, hidrodinámica, gas cooling, formación estelar, evolución estelar, y SN y BH feedback, todos ellos no lineales y por ello difíciles de describir con modelos puramente analíticos. Otros modelos, los semi-analíticos, se basan en simulaciones de únicamente materia oscura y están, por tanto, sesgados al igual que éstas. Por todo esto, las simulaciones cosmológicas hidrodinámicas son la mejor herramienta para realizar los “experimentos controlados” de formación y evolución de galaxias.

    Tras tres décadas de mejoras en las simulaciones numéricas, solo ahora los trabajos teóricos pueden reproducir simultáneamente las propiedades observadas de las galaxias y del medio interestelar (e.g. EAGLE, Schaye et al. 2015, MNRAS, 446, 521; ILLUSTRIS, Vogelsberger et al., 2014, Nature, 509, 177); en particular, las funciones de luminosidad y de masa de las galaxias, las relaciones entre tamaño y masa, entre metalicidad y masa, entre otras muchas propiedades están reproducidas en un amplio rango de masas de galaxias.

    El grupo de astrofísica numérica trabaja en una variedad de temas científicos relacionados con la evolución de las galaxias y la estructura a gran escala del universo. La experiencia abarca desde la estructura interna de las galaxias enanas y de bajo brillo superficial, la Vía Láctea y sus galaxias satélite, el estudio de las galaxias en grupos y agrupaciones, hasta las grandes simulaciones cosmológicas de la estructura del universo. El grupo colabora con la mayoría de los grupos de investigación de IAC que trabajan en astrofísica extragaláctica y cosmología.

    Investigador principal
    Co investigador principal
    Colaboradores
    Prof.
    Sadegh Khochfar
    Prof.
    Joop Schaye
    Dr.
    Yannick Bahé
    Prof.
    Gustavo Yepes
    Prof.
    Daisuke Kawata
    Prof.
    Andrea Macciò
    Prof.
    Alexander Knebe
    Dr.
    Hidenobu Yashima

    Publicaciones relacionadas

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      Angthopo, J. et al.

      Fecha de publicación:

      4
      2021
      Número de citas
      13
    • Self-interacting dark matter and the delay of supermassive black hole growth
      Using cosmological hydrodynamic simulations with physically motivated models of supermassive black hole (SMBH) formation and growth, we compare the assembly of Milky Way-mass (M vir ≍ 7 × 10 11 M ☉ at z = 0) galaxies in cold dark matter (CDM) and self-interacting dark matter (SIDM) models. Our SIDM model adopts a constant cross-section of 1 cm 2 g
      Cruz, A. et al.

      Fecha de publicación:

      1
      2021
      Número de citas
      10
    • Stellar splashback: the edge of the intracluster light
      We examine the outskirts of galaxy clusters in the C-EAGLE simulations to quantify the 'edges' of the stellar and dark matter distribution. The radius of the steepest slope in the dark matter, commonly used as a proxy for the splashback radius, is located at $\sim \, r_{200 \rm m}$ ; the strength and location of this feature depends on the recent
      Deason, Alis J. et al.

      Fecha de publicación:

      1
      2021
      Número de citas
      31
    • The discovery of the most UV-Ly α luminous star-forming galaxy: a young, dust- and metal-poor starburst with QSO-like luminosities
      We report the discovery of BOSS-EUVLG1 at z = 2.469, by far the most luminous, almost un-obscured star-forming galaxy known at any redshift. First classified as a QSO within the Baryon Oscillation Spectroscopic Survey, follow-up observations with the Gran Telescopio Canarias reveal that its large luminosity, M UV ≃ -24.40 and log(L Lyα/erg s -1) ≃
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      Fecha de publicación:

      9
      2020
      Número de citas
      15
    • The First Billion Years project: Finding infant globular clusters at z = 6
      Aims: We aim to conduct an assessment of the demographics of substructures in cosmological simulations to identify low-mass stellar systems at high redshift, with a particular focus on globular cluster (GC) candidates. Methods: We explored a suite of high-resolution cosmological simulations from the First Billion Years Project (FiBY) at z ≥ 6. All
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      Fecha de publicación:

      9
      2020
      Número de citas
      18
    • NIHAO XXIV: rotation- or pressure-supported systems? Simulated Ultra Diffuse Galaxies show a broad distribution in their stellar kinematics
      In recent years, a new window on galaxy evolution opened, thanks to the increasing discovery of galaxies with a low-surface brightness, such as Ultra Diffuse Galaxies (UDGs). The formation mechanism of these systems is still a much debated question and so are their kinematical properties. In this work, we address this topic by analysing the stellar
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      Fecha de publicación:

      7
      2020
      Número de citas
      18
    • Constraining the inner density slope of massive galaxy clusters
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      Fecha de publicación:

      6
      2020
      Número de citas
      23
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      Brook, Chris B. et al.

      Fecha de publicación:

      4
      2020
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      12
    • Kinematic analysis of eagle simulations: evolution of λ<SUB>Re</SUB> and its connection with mergers and gas accretion
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      Walo-Martín, D. et al.

      Fecha de publicación:

      5
      2020
      Número de citas
      21
    • The mass of our Galaxy from satellite proper motions in the Gaia era
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      Fecha de publicación:

      4
      2020
      Número de citas
      52
    • Sub one per cent mass fractions of young stars in red massive galaxies
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      Salvador-Rusiñol, Núria et al.

      Fecha de publicación:

      2
      2020
      Número de citas
      40
    • The intracluster light as a tracer of the total matter density distribution: a view from simulations
      By using deep observations of clusters of galaxies, it has been recently found that the projected stellar mass density closely follows the projected total (dark and baryonic) mass density within the innermost ∼140 kpc. In this work, we aim to test these observations using the Cluster-EAGLE simulations, comparing the projected densities inferred
      Alonso Asensio, Isaac et al.

      Fecha de publicación:

      4
      2020
      Número de citas
      50
    • Deep spectroscopy in nearby galaxy clusters - V. The Perseus cluster
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      Fecha de publicación:

      3
      2020
      Número de citas
      16
    • Signatures of the Galactic bar in high-order moments of proper motions measured by Gaia
      Our location in the Milky Way provides an exceptional opportunity to gain insight on the galactic evolution processes, and complement the information inferred from observations of external galaxies. Since the Milky Way is a barred galaxy, the study of motions of individual stars in the bulge and disc is useful to understand the role of the bar. The
      Palicio, Pedro A. et al.

      Fecha de publicación:

      2
      2020
      Número de citas
      2
    • One simulation to have them all: performance of the Bias Assignment Method against N-body simulations
      In this paper, we demonstrate that the information encoded in one single (sufficiently large) N-body simulation can be used to reproduce arbitrary numbers of halo catalogues, using approximated realizations of dark matter density fields with different initial conditions. To this end, we use as a reference one realization (from an ensemble of 300)
      Balaguera-Antolínez, A. et al.

      Fecha de publicación:

      1
      2020
      Número de citas
      24
    • The Pristine survey - VI. The first three years of medium-resolution follow-up spectroscopy of Pristine EMP star candidates
      We present the results of a 3-yr long, medium-resolution spectroscopic campaign aimed at identifying very metal-poor stars from candidates selected with the CaHK, metallicity-sensitive Pristine survey. The catalogue consists of a total of 1007 stars, and includes 146 rediscoveries of metal-poor stars already presented in previous surveys, 707 new
      Aguado, David S. et al.

      Fecha de publicación:

      12
      2019
      Número de citas
      65
    • Machine learning in APOGEE. Identification of stellar populations through chemical abundances
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      Garcia-Dias, Rafael et al.

      Fecha de publicación:

      9
      2019
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      12
    • Formation of ultra-diffuse galaxies in the field and in galaxy groups
      We study ultra-diffuse galaxies (UDGs) in zoom in cosmological simulations, seeking the origin of UDGs in the field versus galaxy groups. We find that while field UDGs arise from dwarfs in a characteristic mass range by multiple episodes of supernova feedback (Di Cintio et al.), group UDGs may also form by tidal puffing up and they become quiescent
      Jiang, Fangzhou et al.

      Fecha de publicación:

      8
      2019
      Número de citas
      117
    • Conditions for Reionizing the Universe with a Low Galaxy Ionizing Photon Escape Fraction
      We explore scenarios for reionizing the intergalactic medium with low galaxy ionizing photon escape fractions. We combine simulation-based halo mass–dependent escape fractions with an extrapolation of the observed galaxy rest-ultraviolet luminosity functions to solve for the reionization history from z = 20\to 4. We explore the posterior
      Finkelstein, Steven L. et al.

      Fecha de publicación:

      7
      2019
      Número de citas
      280
    • A distance of 13 Mpc resolves the claimed anomalies of the galaxy lacking dark matter
      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
      Trujillo, I. et al.

      Fecha de publicación:

      6
      2019
      Número de citas
      124

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