Using stellar kinematics measurements, we investigate the growth of massive, quiescent galaxies from z ∼2 to today. We present X-Shooter spectra from the UV to NIR and dynamical mass measurements of five quiescent massive (> 10 11 M ⊙ ) galaxies at z ∼ 2. This triples the sample of z > 1.5 galaxies with well constrained (δσ < 100km s −1 ) velocity dispersion measurements. From spectral population synthesis modeling we find that these galaxies have stellar ages that range from 0.5-2 Gyr, with no signs of ongoing star formation. We measure velocity dispersions (290-450 km s −1 ) from stellar absorption lines and find that they are 1.6-2.1 times higher than those of galaxies in the Sloan Digital Sky Survey at the same mass. Sizes are measured using GALFIT from Hubble Space Telescope Wide Field Camera 3 H 160 and UDS K-band images. The dynamical masses correspond well to the spectral energy distribution based stellar masses, with dynamical masses that are ∼ 15% higher. We find that M * /M dyn may decrease slightly with time, which could reflect the increase of the dark matter fraction within an increasing effective radius. We combine different stellar kinematic studies from the literature, and examine the structural evolution from z ∼ 2 to z ∼ 0: we confirm that at fixed dynamical mass, the effective radius increases by a factor of ∼ 2.8, and the velocity dispersion decreases by a factor of ∼ 1.7. The mass density within one effective radius decreases by a factor of ∼ 20, while within a fixed physical radius (1 kpc) it decreases only mildly (factor of ∼ 2). When we allow for an evolving mass limit by selecting a population of galaxies at fixed number density, a stronger size growth with time is found (factor of ∼ 4), velocity dispersion decreases by a factor of ∼ 1.4, and interestingly, the mass density within 1 kpc is consistent with no evolution. This finding suggests that massive quiescent galaxies at z ∼ 2 grow inside-out, consistent with the expectations from minor mergers.

We describe the selection of galaxies targeted in eight low redshift clusters (APMCC0917, A168, A4038, EDCC442, A3880, A2399, A119 and A85; 0.029 < z < 0.058) as part of the Sydney-AAO Multi-Object integral field Spectrograph Galaxy Survey (SAMI-GS). We have conducted a redshift survey of these clusters using the AAOmega multi-object spectrograph on the 3.9m Anglo-Australian Telescope. The redshift survey is used to determine cluster membership and to characterise the dynamical properties of the clusters. In combination with existing data, the survey resulted in 21,257 reliable redshift measurements and 2899 confirmed cluster member galaxies. Our redshift catalogue has a high spectroscopic completeness (∼ 94%) for r petro ≤ 19.4 and clustercentric distances R < 2R 200 . We use the confirmed cluster member positions and redshifts to determine cluster velocity dispersion, R 200 , virial and caustic masses, as well as cluster structure. The clusters have virial masses 14.25 ≤ log(M 200 /M ⊙ ) ≤ 15.19. The cluster sample exhibits a range of dynamical states, from relatively relaxed-appearing systems, to clusters with strong indications of merger-related substructure. Aperture-and PSF-matched photometry are derived from SDSS and VST/ATLAS imaging and used to estimate stellar masses. These estimates, in combination with the redshifts, are used to define the input target catalogue for the cluster portion of the SAMI-GS. The primary SAMI-GS cluster targets have R

Misalignment of gas and stellar rotation in galaxies can give clues to the origin and processing of accreted gas. Integral field spectroscopic observations of 1213 galaxies from the SAMI Galaxy Survey show that 11% of galaxies with fitted gas and stellar rotation are misaligned by more than 30 • in both field/group and cluster environments. Using SAMI morphological classifications and Sérsic indices, the misalignment fraction is 45 ± 6% in early-type galaxies, but only 5 ± 1% in late-type galaxies. The distribution of position angle offsets is used to test the physical drivers of this difference. Slower dynamical settling time of the gas in elliptical stellar mass distributions accounts for a small increase in misalignment in early-type galaxies. However, gravitational dynamical settling time is insufficient to fully explain the observed differences between early-and late-type galaxies in the distributions of the gas/stellar position angle offsets. LTGs have primarily accreted gas close to aligned rather than settled from misaligned based on analysis of the skewed distribution of PA offsets compared to a dynamical settling model. Local environment density is less important in setting the misalignment fractions than morphology, suggesting that mergers are not the main source of accreted gas in these disks. Cluster environments are found to have gas misalignment driven primarily by cluster processes not by gas accretion.

We present a study of the evolution of the galaxy Velocity Dispersion Function (VDF) from z = 0 to z = 1.5 using photometric data from the UDS and NMBS COSMOS surveys. The VDF has been measured locally using direct kinematic measurements from the Sloan Digital Sky Survey, but direct studies of the VDF at high redshift are difficult as they require velocity dispersion measurements of many thousands of galaxies. Taylor et al. (2010) demonstrated that dynamical and stellar mass are linearly related when the structure of the galaxy is accounted for. We show that the stellar mass, size and Sérsic index can reliably predict the velocity dispersions of SDSS galaxies. We apply this relation to galaxies at high redshift and determine the evolution of the inferred VDF. We find that the VDF at z ∼ 0.5 is very similar to the VDF at z = 0. At higher redshifts, we find that the number density of galaxies with dispersions 200 km/s is lower, but the number of high dispersion galaxies is constant or even higher. At fixed cumulative number density, the velocity dispersions of galaxies with log N[ Mpc −3 ] < −3.5 increase with time by a factor of ∼ 1.4 from z ∼ 1.5 − 0, whereas the dispersions of galaxies with lower number density are approximately constant or decrease with time. The VDF appears to show less evolution than the stellar mass function, particularly at the lowest number densities. We note that these results are still somewhat uncertain and we suggest several avenues for further calibrating the inferred velocity dispersions.

Recent observations from integral field spectroscopy (IFS) indicate that the fraction of galaxies that are slow rotators, F SR , depends primarily on stellar mass, with no significant dependence on environment. We investigate these trends and the formation paths of slow rotators (SRs) using the EAGLE and HYDRANGEA hydro-dynamical simulations. EAGLE consists of several cosmological boxes of volumes up to (100 Mpc) 3 , while HYDRANGEA consists of 24 cosmological simulations of galaxy clusters and their environment. Together they provide a statistically significant sample in the stellar mass range 10 9.5 M ⊙ − 10 12.3 M ⊙ , of 16, 358 galaxies. We construct IFS-like cubes and measure stellar spin parameters, λ R , and ellipticities, allowing us to classify galaxies into slow/fast rotators as in observations. The simulations display a primary dependence of F SR on stellar mass, with a weak dependence on environment. At fixed stellar mass, satellite galaxies are more likely to be SRs than centrals. F SR shows a dependence on halo mass at fixed stellar mass for central galaxies, while no such trend is seen for satellites. We find that ≈ 70% of SRs at z = 0 have experienced at least one merger with mass ratio 0.1, with dry mergers being at least twice more common than wet mergers. Individual dry mergers tend to decrease λ R , while wet mergers mostly increase it. However, 30% of SRs at z = 0 have not experienced mergers, and those inhabit halos with median spins twice smaller than the halos hosting the rest of the SRs. Thus, although the formation paths of SRs can be varied, dry mergers and/or halos with small spins dominate.

We investigate the relationship between stellar and gas specific angular momentum j, stellar mass M * and optical morphology for a sample of 488 galaxies extracted from the SAMI Galaxy Survey. We find that j, measured within one effective radius, monotonically increases with M * and that, for M * >10 9.5 M , the scatter in this relation strongly correlates with optical morphology (i.e., visual classification and Sérsic index). These findings confirm that massive galaxies of all types lie on a plane relating mass, angular momentum and stellar light distribution, and suggest that the largescale morphology of a galaxy is regulated by its mass and dynamical state. We show that the significant scatter in the M * − j relation is accounted for by the fact that, at fixed stellar mass, the contribution of ordered motions to the dynamical support of galaxies varies by at least a factor of three. Indeed, the stellar spin parameter (quantified via λ R ) correlates strongly with Sérsic and concentration indices. This correlation is particularly strong once slow-rotators are removed from the sample, showing that late-type galaxies and early-type fast rotators form a continuous class of objects in terms of their kinematic properties.

We present the first detection of mass dependent galactic spin alignments with local cosmic filaments with > 2σ confidence using IFS kinematics. The 3D network of cosmic filaments is reconstructed on Mpc scales across GAMA fields using the cosmic web extractor DisPerSe. We assign field galaxies from the SAMI survey to their nearest filament segment in 3D and estimate the degree of alignment between SAMI galaxies' kinematic spin axis and their nearest filament in projection. Low-mass galaxies align their spin with their nearest filament while higher mass counterparts are more likely to display an orthogonal orientation. The stellar transition mass from the first trend to the second is bracketed between 10 10.4 M and 10 10.9 M , with hints of an increase with filament scale. Consistent signals are found in the Horizon-AGN cosmological hydrodynamic simulation. This supports a scenario of early angular momentum build-up in vorticity rich quadrants around filaments at low stellar mass followed by progressive flip of spins orthogonal to the cosmic filaments through mergers at high stellar mass. Conversely, we show that dark-matter only simulations post-processed with a semi-analytic model treatment of galaxy formation struggles to reproduce this alignment signal. This suggests that gas physics is key in enhancing the galaxy-filament alignment.

We present the second data release of the Large Early Galaxy Astrophysics Census (LEGA-C), an ESO 130−night public spectroscopic survey conducted with VIMOS on the Very Large Telescope. We release 1988 spectra with typical continuum S/N 20Å −1 of galaxies at 0.6 z 1.0, each observed for ∼ 20 hours and fully reduced with a custom-built pipeline. We also release a catalog with spectroscopic redshifts, emission line fluxes, Lick/IDS indices, and observed stellar and gas velocity dispersions that are spatially integrated quantities including both rotational motions and genuine dispersion. To illustrate the new parameter space in the intermediate redshift regime probed by LEGA-C we explore relationships between dynamical and stellar population properties. The star-forming galaxies typically have observed stellar velocity dispersions of ∼ 150 km s −1 and strong Hδ absorption (Hδ A ∼ 5Å), while passive galaxies have higher observed stellar velocity dispersions (∼ 200 km s −1 ) and weak Hδ absortion (Hδ A ∼ 0Å). Strong [OIII]5007/Hβ ratios tend to occur mostly for galaxies with weak Hδ A or galaxies with higher observed velocity dispersion. Beyond these broad trends, we find a large diversity of possible combinations of rest-frame colors, absorption line strengths and emission line detections, illustrating the utility of spectroscopic measurements to more accurately understand galaxy evolution. By making the spectra and value-added catalogs publicly available we encourage the community to take advantage of this very substantial investment in telescope time provided by ESO.