showing 5 related works from this author
Massive relic galaxies prefer dense environments
2016
We study the preferred environments of $z \sim 0$ massive relic galaxies ($M_\star \gtrsim 10^{10}~\mathrm{M_\odot}$ galaxies with little or no growth from star formation or mergers since $z \sim 2$). Significantly, we carry out our analysis on both a large cosmological simulation and an observed galaxy catalogue. Working on the Millennium I-WMAP7 simulation we show that the fraction of today massive objects which have grown less than 10 per cent in mass since $z \sim 2$ is ~0.04 per cent for the whole massive galaxy population with $M_\star > 10^{10}~\mathrm{M_\odot}$. This fraction rises to ~0.18 per cent in galaxy clusters, confirming that clusters help massive galaxies remain unalter…
Young ages and other intriguing properties of massive compact galaxies in the local Universe
2012
We characterize the kinematics, morphology, stellar populations and star formation histories of a sample of massive compact galaxies in the nearby Universe, which might provide a closer look at the nature of their high-redshift (z >rsim 1.0) massive counterparts. We find that nearby compact massive objects show elongated morphologies and are fast rotators. New high-quality long-slit spectra show that they have young mean luminosity-weighted ages (2 Gyr) and metallicities solar or above ([Z/H] >rsim 0.0). No significant stellar population gradients are found. The analysis of their star formation histories suggests that these objects have experienced recently enormous bursts which, in some c…
SATELLITES AROUND MASSIVE GALAXIES SINCE z ∼ 2: CONFRONTING THE MILLENNIUM SIMULATION WITH OBSERVATIONS
2012
Minor merging has been postulated as the most likely evolutionary path to produce the increase in size and mass observed in the massive galaxies since z$\sim$2. In this Letter, we test directly this hypothesis comparing the population of satellites around massive galaxies in cosmological simulations versus the observations. We use state-of-the-art, publically available, Millennium I and II simulations and the associated semi-analytical galaxy catalogues to explore the time evolution of the fraction of massive galaxies that have satellites, the number of satellites per galaxy, the projected distance at which the satellite locate from the host galaxy, and the mass ratio between the host galax…
Expected number of massive galaxy relics in the present-day Universe
2013
The number of present-day massive galaxies that has 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 form at z>2 which have evolved in stellar mass less than 10% and 30%. We find that only a small fraction of the massive galaxies already form at z~2 have remained almost unaltered since their formation (<2% with Delta_M*/M*<0.1 and <8% with Delta_M*/M*<0.3). These fractions correspond to the following number densities of massive relics…
The intriguing properties of local compact massive galaxies: What are they?
2012
AbstractStudying the properties of the few compact massive galaxies that exist in the local Universe (Trujillo et al. 2009) might provide a closer look to the nature of their high redshift (z ≥ 1.0) massive counterparts. By this means we have characterized their main kinematics, structural properties, stellar populations and star formation histories with a set of new high quality spectroscopic and imaging data (Ferré-Mateu et al. 2012 and Trujillo et al. 2012). These galaxies seem to be truly unique, as they do not follow the characteristic kinematics, stellar surface mass density profiles and stellar population patterns of present-day massive ellipticals or spirals of similar mass. They ar…