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Massive starburst galaxies in the early Universe are estimated to have depletion times of $sim 100$ Myr and thus be able to convert their gas very quickly into stars, possibly leading to a rapid quenching of their star formation. For these reasons, they are considered progenitors of massive early-type galaxies (ETGs). In this paper, we study two high-$z$ starbursts, AzTEC/C159 ($zsimeq 4.57$) and J1000+0234 ($zsimeq 4.54$), observed with ALMA in the [CII] 158-$mu$m emission line. These observations reveal two massive and regularly rotating gaseous discs. A 3D modelling of these discs returns rotation velocities of about $500$ km/s and gas velocity dispersions as low as $approx 20$ km/s, leading to very high ratios between regular and random motion ($V/sigma {lower.7exhbox{$;stackrel{textstyle>}{sim};$}} 20$), at least in AzTEC/C159. The mass decompositions of the rotation curves show that both galaxies are highly baryon-dominated with gas masses of $approx 10^{11}M_{odot}$, which, for J1000+0234, is significantly higher than previous estimates. We show that these high-$z$ galaxies overlap with $z=0$ massive ETGs in the ETG analogue of the stellar-mass Tully-Fisher relation once their gas is converted into stars. This provides dynamical evidence of the connection between massive high-$z$ starbursts and ETGs, although the transformation mechanism from fast rotating to nearly pressure-supported systems remains unclear.
There is a large consensus that gas in high-$z$ galaxies is highly turbulent, because of a combination of stellar feedback processes and gravitational instabilities driven by mergers and gas accretion. In this paper, we present the analysis of a samp
Early-type dwarf galaxies, once believed to be simple systems, have recently been shown to exhibit an intriguing diversity in structure and stellar content. To analyze this further, we started the SMAKCED project, and obtained deep H-band images for
We study the evidence for a diversity of formation processes in early-type galaxies by presenting the first complete volume-limited sample of slow rotators with both integral-field kinematics from the ATLAS3D Project and high spatial resolution photo
I present an overview of new observations of atomic and molecular gas in early-type galaxies, focusing on the Atlas3D project. Our data on stellar kinematics, age and metallicity, and ionized gas kinematics allow us to place the cold gas into the bro
We present a detailed study of the variable star population of Eridanus II (Eri II), an ultra-faint dwarf galaxy that lies close to the Milky Way virial radius. We analyze multi-epoch $g,r,i$ ground-based data from Goodman and the Dark Energy Camera,