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We show that the observed upper bound on the line-of-sight velocity dispersion of the stars in an early-type galaxy, sigma<400km/s, may have a simple dynamical origin within the LCDM cosmological model, under two main hypotheses. The first is that most of the stars now in the luminous parts of a giant elliptical formed at redshift z>6. Subsequently, the stars behaved dynamically just as an additional component of the dark matter. The second hypothesis is that the mass distribution characteristic of a newly formed dark matter halo forgets such details of the initial conditions as the stellar collisionless matter that was added to the dense parts of earlier generations of halos. We also assume that the stellar velocity dispersion does not evolve much at z<6, because a massive host halo grows mainly by the addition of material at large radii well away from the stellar core of the galaxy. These assumptions lead to a predicted number density of ellipticals as a function of stellar velocity dispersion that is in promising agreement with the Sloan Digital Sky Survey data.
We present Gran-Telescopio-Canarias/OSIRIS optical spectra of 4 of the most compact and massive early-type galaxies in the Groth Strip Survey at redshift z~1, with effective radii Reff=0.5-2.4 kpc and photometric stellar masses Mstar=1.2-4x10^11 Msun
We analyze 40 cosmological re-simulations of individual massive galaxies with present-day stellar masses of $M_{*} > 6.3 times 10^{10} M_{odot}$ in order to investigate the physical origin of the observed strong increase in galaxy sizes and the decre
Using the exquisite depth of the Hubble Ultra Deep Field (HUDF12 programme) dataset, we explore the ongoing assembly of the outermost regions of the most massive galaxies ($rm M_{rm stellar}geq$ 5$times$10$^{10}$ M$_{odot}$) at $z leq$ 1. The outskir
We present tables of velocity dispersions derived from CALIFA V1200 datacubes using Pipe3D. Four different dispersions are extracted from emission (ionized gas) or absorption (stellar) spectra, with two spatial apertures (5 and 30). Stellar and ioniz
We use high spatial resolution stellar velocity maps from the Gemini GMOS integral-field spectrograph (IFS) and wide-field velocity maps from the McDonald Mitchell IFS to study the stellar velocity profiles and kinematic misalignments from $sim 200$