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We present an interstellar medium and stellar population analysis of three spectroscopically confirmed $z>7$ galaxies in the ERO JWST NIRCam and JWST NIRSpec data of the SMACS J0723.3-7327 cluster. We use the Bayesian spectral energy distribution (SED) fitting code \texttt{Prospector} with a flexible star-formation history (SFH), a variable dust attenuation law, and a self-consistent model of nebular emission (continuum and emission lines). Importantly, we self-consistently fit both the emission line fluxes from JWST NIRSpec and the broad-band photometry from JWST NIRCam, taking into account slit-loss effects. We find that these three $z=7.6-8.5$ galaxies ($M_{\star}\approx10^{8}~M_{\odot}$) are young with rising SFHs and mass-weighted ages of $3-4$ Myr, though we find indications for underlying older stellar populations. The inferred gas-phase metallicities broadly agree with the direct metallicity estimates from the auroral lines. The galaxy with the lowest gas-phase metallicity ($\mathrm{Z}_{\rm gas}=0.06~\mathrm{Z}_{\odot}$) has a steeply rising SFH, is very compact ($, 14 pages, 9 figures; accepted for publication in MNRAS

We explore local and global dynamical differences between the kinematics of ionised gas and stars in a sample of galaxies from Data Release 3 of the SAMI Galaxy Survey. We find better agreement between local (i.e., comparing on a spaxel-to-spaxel basis) velocities and dispersion of gas and stars in younger systems as with previous work on the asymmetric drift in galaxies, suggesting that the dynamics of stars and ionised gas are initially coupled. The intrinsic scatter around the velocity and dispersion relations increases with increasing stellar age and mass, suggesting that subsequent mechanisms such as internal processes, divergent star formation and assembly histories also play a role in setting and altering the dynamics of galaxies. The global (flux-weighted) dynamical support of older galaxies is hotter than in younger systems. We find that the ionised gas in galaxies is almost always dynamically colder than the stars with a steeper velocity gradient. In absolute terms, the local difference in velocity dispersion is more pronounced than the local difference in velocity, possibly reflecting inherent differences in the impact of turbulence, inflow and/or feedback on gas compared to stars. We suggest how these findings may be taken into account when comparing high and low redshift galaxy samples to infer dynamical evolution., Comment: 11 pages, 9 figures, 1 table, accepted for publication in MNRAS

We present SAMI-HI, a survey of the atomic hydrogen content of 296 galaxies with integral field spectroscopy available from the SAMI Galaxy Survey. The sample spans nearly 4 dex in stellar mass ($M_\star = 10^{7.4}-10^{11.1}~ \rm M_\odot$), redshift $z, Comment: 18 pages, 12 figures. Accepted for publication in MNRAS

We investigate the impact of environment on the internal mass distribution of galaxies using the Middle Ages Galaxy Properties with Integral field spectroscopy (MAGPI) survey. We use 2D resolved stellar kinematics to construct Jeans dynamical models for galaxies at mean redshift $z \sim 0.3$, corresponding to a lookback time of $3-4$ Gyr. The internal mass distribution for each galaxy is parameterised by the combined mass density slope $\gamma$ (baryons $+$ dark matter), which is the logarithmic change of density with radius. We use a MAGPI sample of 28 galaxies from low-to-mid density environments and compare to density slopes derived from galaxies in the high density Frontier Fields clusters in the redshift range $0.29, Comment: Accepted for publication in MNRAS

We investigate the change in mean stellar population age and metallicity ([Z/H]) scaling relations for quiescent galaxies from intermediate redshift ($0.60\leq z\leq0.76$) using the LEGA-C Survey, to low redshift ($0.014\leq z\leq0.10$) using the SAMI Galaxy Survey. We find that, similarly to their low-redshift counterparts, the stellar metallicity of quiescent galaxies at $0.60\leq z\leq 0.76$ closely correlates with $M_*/R_\mathrm{e}$ (a proxy for the gravitational potential or escape velocity), in that galaxies with deeper potential wells are more metal-rich. This supports the hypothesis that the relation arises due to the gravitational potential regulating the retention of metals, by determining the escape velocity required by metal-rich stellar and supernova ejecta to escape the system and avoid being recycled into later stellar generations. On the other hand, we find no correlation between stellar age and $M_*/R_\mathrm{e}^2$ (stellar mass surface density $\Sigma$) in the LEGA-C sample, despite this being a strong relation at low redshift. We consider this change in the age--$\Sigma$ relation in the context of the redshift evolution of the star-forming and quiescent populations in the mass--size plane, and find our results can be explained as a consequence of galaxies forming more compactly at higher redshifts, and remaining compact throughout their evolution. Furthermore, galaxies appear to quench at a characteristic surface density that decreases with decreasing redshift. The $z\sim 0$ age--$\Sigma$ relation is therefore a result of building up the quiescent and star-forming populations with galaxies that formed at a range of redshifts and so a range of surface densities., Comment: 18 pages, 11 figures, accepted to MNRAS

Aims. We present a non-parametric morphology analysis of the stellar continuum and nebular emission lines for a sample of local galaxies. We explore the dependence of the various morphological parameters on wavelength and morphological type. Our goal is to quantify the difference in morphology between the stellar and nebular components. Methods. We derived the non-parametric morphological indicators of 364 galaxies from the Calar Alto Legacy Integral Field Area (CALIFA) Survey. To calculate those indicators, we applied the StatMorph package on the high-quality integral field spectroscopic data cubes, as well as to the most prominent nebular emission-line maps, namely [O III]λ5007, Hα, and [N II]λ6583. Results. We show that the physical size of galaxies, M20 index, and concentration have a strong gradient from blue to red optical wavelengths. We find that the light distribution of the nebular emission is less concentrated than the stellar continuum. A comparison between the non-parametric indicators and the galaxy physical properties revealed a very strong correlation of the concentration with the specific star formation rate and morphological type. Furthermore, we explore how the galaxy inclination affects our results. We find that edge-on galaxies show a more rapid change in physical size and concentration with increasing wavelength due to the increase in the optical free path. Conclusions. We conclude that the apparent morphology of galaxies originates from the pure stellar distribution, but the morphology of the interstellar medium presents differences with respect to the morphology of the stellar component. Our analysis also highlights the importance of dust attenuation and galaxy inclination in the measurement of non-parametric morphological indicators, especially in the wavelength range 4000−5000 Å.

We present a new set of index-based measurements of [$\alpha$/Fe] for a sample of 2093 galaxies in the SAMI Galaxy Survey. Following earlier work, we fit a global relation between [$\alpha$/Fe] and the galaxy velocity dispersion $\sigma$ for red sequence galaxies, [$\alpha$/Fe]=(0.378$\pm$0.009)log($\sigma$/100)+(0.155$\pm$0.003). We observe a correlation between the residuals and the local environmental surface density, whereas no such relation exists for blue cloud galaxies. In the full sample, we find that elliptical galaxies in high-density environments are $\alpha$-enhanced by up to 0.057$\pm$0.014 dex at velocity dispersions $\sigma$, Comment: 15 pages, 9 figures. Revised after comments from referee

We use the MaNGA integral-field spectroscopic survey of low-redshift galaxies to compare the stellar populations of the bulge and disc components, identified from their Sersic profiles, for various samples of galaxies. Bulge dominated regions tend to be more metal-rich and have slightly older stellar ages than their associated disc dominated regions. The metallicity difference is consistent with the deeper gravitational potential in bulges relative to discs, which allows bulges to retain more of the metals produced by stars. The age difference is due to star formation persisting longer in discs relative to bulges. Relative to galaxies with lower stellar masses, galaxies with higher stellar masses tend to have bulge dominated regions that are more metal-rich and older (in light-weighted measurements) than their disc dominated regions. This suggests high-mass galaxies quench from the inside out, while lower-mass galaxies quench across the whole galaxy simultaneously. Early-type galaxies tend to have bulge dominated regions the same age as their disc dominated regions, while late-type galaxies tend to have disc dominated regions significantly younger than their bulge dominated regions. Central galaxies tend to have a greater metallicity difference between their bulge dominated regions and disc dominated regions than satellite galaxies at similar stellar mass. This difference may be explained by central galaxies being subject to mergers or extended gas accretion bringing new, lower-metallicity gas to the disc, thereby reducing the average metallicity and age of the stars; quenching of satellite discs may also play a role., Accepted by PASA

Finding and characterising the first galaxies that illuminated the early Universe at cosmic dawn is pivotal to understand the physical conditions and the processes that led to the formation of the first stars. In the first few months of operations, imaging from the James Webb Space Telescope (JWST) have been used to identify tens of candidates of galaxies at redshift (z) greater than 10, less than 450 million years after the Big Bang. However, none of these candidates has yet been confirmed spectroscopically, leaving open the possibility that they are actually low-redshift interlopers. Here we present spectroscopic confirmation and analysis of four galaxies unambiguously detected at redshift 10.3, Comment: 32 pages, 8 figures, accepted to Nature Astronomy

We analyse the chemical properties of three z~8 galaxies behind the galaxy cluster SMACS J0723.3-7327, observed as part of the Early Release Observations programme of the James Webb Space Telescope (JWST). Exploiting [O III]4363 auroral line detections in NIRSpec spectra, we robustly apply the direct Te method for the very first time at such high redshift, measuring metallicities ranging from extremely metal poor (12+log(O/H)~7) to about one-third solar. We also discuss the excitation properties of these sources, and compare them with local strong-line metallicity calibrations. We find that none of the considered diagnostics match simultaneously the observed relations between metallicity and strong-line ratios for the three sources, implying that a proper re-assessment of the calibrations may be needed at these redshifts. On the mass-metallicity plane, the two galaxies at z~7.6 (log(M*/M_sun) = 8.1, 8.7) have metallicities that are consistent with the extrapolation of the mass-metallicity relation at z~2-3, while the least massive galaxy at z~8.5 (log(M*/M_sun) = 7.8) shows instead a significantly lower metallicity . The three galaxies show different level of offset relative to the Fundamental Metallicity Relation, with two of them (at z~7.6) being marginally consistent, while the z~8.5 source deviating significantly, being probably far from the smooth equilibrium between gas flows, star formation and metal enrichment in place at later epochs., 13 pages, 7 figures. Accepted for publication on MNRAS

Large galaxy samples from multi-object IFS surveys now allow for a statistical analysis of the z~0 galaxy population using resolved kinematics. However, the improvement in number statistics comes at a cost, with multi-object IFS survey more severely impacted by the effect of seeing and lower S/N. We present an analysis of ~1800 galaxies from the SAMI Galaxy Survey and investigate the spread and overlap in the kinematic distributions of the spin parameter proxy $\lambda_{Re}$ as a function of stellar mass and ellipticity. For SAMI data, the distributions of galaxies identified as regular and non-regular rotators with \textsc{kinemetry} show considerable overlap in the $\lambda_{Re}$-$\varepsilon_e$ diagram. In contrast, visually classified galaxies (obvious and non-obvious rotators) are better separated in $\lambda_{Re}$ space, with less overlap of both distributions. Then, we use a Bayesian mixture model to analyse the observed $\lambda_{Re}$-$\log(M_*/M_{\odot})$ distribution. Below $\log(M_{\star}/M_{\odot})\sim10.5$, a single beta distribution is sufficient to fit the complete $\lambda_{Re}$ distribution, whereas a second beta distribution is required above $\log(M_{\star}/M_{\odot})\sim10.5$ to account for a population of low-$\lambda_{Re}$ galaxies. While the Bayesian mixture model presents the cleanest separation of the two kinematic populations, we find the unique information provided by visual classification of kinematic maps should not be disregarded in future studies. Applied to mock-observations from different cosmological simulations, the mixture model also predicts bimodal $\lambda_{Re}$ distributions, albeit with different positions of the $\lambda_{Re}$ peaks. Our analysis validates the conclusions from previous smaller IFS surveys, but also demonstrates the importance of using kinematic selection criteria that are dictated by the quality of the observed or simulated data., Comment: 30 pages and 17 figures, accepted for publication in MNRAS. Abstract abridged for Arxiv. The key figures of the paper are: 3, 7, 8, and 11

The Study of H$\alpha$ from Dwarf Emissions (SH$\alpha$DE) is a high spectral resolution (R=13500) H$\alpha$ integral field survey of 69 dwarf galaxies with stellar masses $10^6, Comment: 19 pages, 13 figures, 5 tables; published in MNRAS

In this work, we investigate how the central stellar metallicity ([Z/H]) of 1363 galaxies from the SAMI galaxy survey is related to their stellar mass and a proxy for the gravitational potential, $\Phi$ = log10(M/M*) - log10($r_e$/kpc). In agreement with previous studies, we find that passive and star-forming galaxies occupy different areas of the [Z/H]-M* plane, with passive galaxies having higher [Z/H] than star-forming galaxies at fixed mass (a difference of 0.23 dex at log10(M/M*)=10.3). We show for the first time that all galaxies lie on the same relation between [Z/H] and $\Phi$, and show that the offset in [Z/H] between passive and star-forming galaxies at fixed $\Phi$ is smaller than or equal to the offset in [Z/H] at fixed mass (an average $\Delta$[Z/H] of 0.11 dex at fixed $\Phi$ compared to 0.21 dex at fixed mass). We then build a simple model of galaxy evolution to explain and understand our results. By assuming that [Z/H] traces $\Phi$ over cosmic time and that the probability that a galaxy quenches depends on both its mass and size, we are able to reproduce these offsets in stellar metallicity with a model containing instantaneous quenching. We therefore conclude that an offset in metallicity at fixed mass cannot by itself be used as evidence of slow quenching processes, in contrast to previous studies. Instead, our model implies that metal-rich galaxies have always been the smallest objects for their mass in a population. Our findings reiterate the need to consider galaxy size when studying stellar populations., Comment: 18 pages, 15 figures. Accepted for publication in MNRAS

Dynamical models for $673$ galaxies at $z=0.6-1.0$ with spatially resolved (long-slit) stellar kinematic data from LEGA-C are used to calibrate virial mass estimates defined as $M_{\rm{vir}}=K \sigma'^2_{\star,\rm{int}} R$, with $K$ a scaling factor, $\sigma'_{\star,\rm{int}}$ the spatially-integrated stellar velocity second moment from the LEGA-C survey and $R$ the effective radius measured from a S\'ersic profile fit to HST imaging. The sample is representative for $M_{\star}>3\times10^{10}~M_{\odot}$ and includes all types of galaxies, irrespective of morphology and color. We demonstrate that using $R=R_{\rm{sma}}$~(the semi-major axis length of the ellipse that encloses 50\% of the light) in combination with an inclination correction on $\sigma'_{\star,\rm{int}}$~produces an unbiased $M_{\rm{vir}}$. We confirm the importance of projection effects on $\sigma'_{\star,\rm{int}}$ by showing the existence of a similar residual trend between virial mass estimates and inclination for the nearby early-type galaxies in the ATLAS$^{\rm{3D}}$~survey. Also, as previously shown, when using a S\'ersic profile-based $R$ estimate, then a S\'{e}rsic index-dependent correction to account for non-homology in the radial profiles is required. With respect to analogous dynamical models for low-redshift galaxies from the ATLAS$^{\rm{3D}}$~survey we find a systematic offset of 0.1 dex in the calibrated virial constant for LEGA-C, which may be due to physical differences between the galaxy samples or an unknown systematic error. Either way, with our work we establish a common mass scale for galaxies across 8 Gyr of cosmic time with a systematic uncertainty of at most 0.1 dex., Comment: Published in ApJ

We investigate the mean locally-measured velocity dispersions of ionised gas ($\sigma_{\rm gas}$) and stars ($\sigma_*$) for 1090 galaxies with stellar masses $\log\,(M_*/M_{\odot}) \geq 9.5$ from the SAMI Galaxy Survey. For star-forming galaxies, $\sigma_*$ tends to be larger than $\sigma_{\rm gas}$, suggesting that stars are in general dynamically hotter than the ionised gas (asymmetric drift). The difference between $\sigma_{\rm gas}$ and $\sigma_*$ ($\Delta\sigma$) correlates with various galaxy properties. We establish that the strongest correlation of $\Delta\sigma$ is with beam smearing, which inflates $\sigma_{\rm gas}$ more than $\sigma_*$, introducing a dependence of $\Delta\sigma$ on both the effective radius relative to the point spread function and velocity gradients. The second-strongest correlation is with the contribution of active galactic nuclei (AGN) (or evolved stars) to the ionised gas emission, implying the gas velocity dispersion is strongly affected by the power source. In contrast, using the velocity dispersion measured from integrated spectra ($\sigma_{\rm aper}$) results in less correlation between the aperture-based $\Delta\sigma$ ($\Delta\sigma_{\rm aper}$) and the power source. This suggests that the AGN (or old stars) dynamically heat the gas without causing significant deviations from dynamical equilibrium. Although the variation of $\Delta\sigma_{\rm aper}$ is much smaller than that of $\Delta\sigma$, a correlation between $\Delta\sigma_{\rm aper}$ and gas velocity gradient is still detected, implying there is a small bias in dynamical masses derived from stellar and ionised gas velocity dispersions., Comment: 18 pages, 13 figures

We study the alignments of galaxy spin axes with respect to cosmic web filaments as a function of various properties of the galaxies and their constituent bulges and discs. We exploit the SAMI Galaxy Survey to identify 3D spin axes from spatially-resolved stellar kinematics and to decompose the galaxy into the kinematic bulge and disc components. The GAMA survey is used to reconstruct the cosmic filaments. The mass of the bulge, defined as the product of stellar mass and bulge-to-total flux ratio M_bulge=M_star x (B/T), is the primary parameter of correlation with spin-filament alignments: galaxies with lower bulge masses tend to have their spins parallel to the closest filament, while galaxies with higher bulge masses are more perpendicularly aligned. M_star and B/T separately show correlations, but they do not fully unravel spin-filament alignments. Other galaxy properties, such as visual morphology, stellar age, star formation activity, kinematic parameters and local environment, are secondary tracers. Focusing on S0 galaxies, we find preferentially perpendicular alignments, with the signal dominated by high-mass S0 galaxies. Studying bulge and disc spin-filament alignments separately reveals additional information about the formation pathways of the corresponding galaxies: bulges tend to have more perpendicular alignments, while discs show different tendencies according to their kinematic features and the mass of the associated bulge. The observed correlation between the flipping of spin-filament alignments and the growth of the bulge can be explained by mergers, which drive both alignment flips and bulge formation., Comment: Accepted for publication in MNRAS. 23 pages, 22 figures, 2 3D models at https://skfb.ly/o9MXv and https://skfb.ly/o9MXz, 5 supplementary figures

We explore a sample of 1492 galaxies with measurements of the mean stellar population properties and the spin parameter proxy, $\lambda_{R_{\rm{e}}}$, drawn from the SAMI Galaxy Survey. We fit a global $\left[\alpha/\rm{Fe}\right]$-$\sigma$ relation, finding that $\left[\alpha/\rm{Fe}\right]=(0.395\pm0.010)\rm{log}_{10}\left(\sigma\right)-(0.627\pm0.002)$. We observe an anti-correlation between the residuals $\Delta\left[\alpha/\rm{Fe}\right]$ and the inclination-corrected $\lambda_{\,R_{\rm{e}}}^{\rm{\,eo}}$, which can be expressed as $\Delta\left[\alpha/\rm{Fe}\right]=(-0.057\pm0.008)\lambda_{\,R_{\rm{e}}}^{\rm{\,eo}}+(0.020\pm0.003)$. The anti-correlation appears to be driven by star-forming galaxies, with a gradient of $\Delta\left[\alpha/\rm{Fe}\right]\sim(-0.121\pm0.015)\lambda_{\,R_{\rm{e}}}^{\rm{\,eo}}$, although a weak relationship persists for the subsample of galaxies for which star formation has been quenched. We take this to be confirmation that disk-dominated galaxies have an extended duration of star formation. At a reference velocity dispersion of 200 km s$^{-1}$, we estimate an increase in half-mass formation time from $\sim$0.5 Gyr to $\sim$1.2 Gyr from low- to high-$\lambda_{\,R_{\rm{e}}}^{\rm{\,eo}}$ galaxies. Slow rotators do not appear to fit these trends. Their residual $\alpha$-enhancement is indistinguishable from other galaxies with $\lambda_{\,R_{\rm{e}}}^{\rm{\,eo}}\lessapprox0.4$, despite being both larger and more massive. This result shows that galaxies with $\lambda_{\,R_{\rm{e}}}^{\rm{\,eo}}\lessapprox0.4$ experience a similar range of star formation histories, despite their different physical structure and angular momentum., Comment: 12 pages, 9 figures

We present spatially resolved stellar kinematics for 797 $z=0.6-1$ galaxies selected from the LEGA-C survey and construct axisymmetric Jeans models to quantify their dynamical mass and degree of rotational support. The survey is $K_s$-band selected, irrespective of color or morphological type, and allows for a first assessment of the stellar dynamical structure of the general $L^*$ galaxy population at large lookback time. Using light profiles from Hubble Space Telescope imaging as a tracer, our approach corrects for observational effects (seeing convolution and slit geometry), and uses well-informed priors on inclination, anisotropy and a non-luminous mass component. Tabulated data include total mass estimates in a series of spherical apertures (1, 5, and 10 kpc; 1$\times$ and 2$\times$\re), as well as rotational velocities, velocity dispersions and anisotropy. We show that almost all star-forming galaxies and $\sim$50\% of quiescent galaxies are rotation-dominated, with deprojected $V/\sigma\sim1-2$. Revealing the complexity in galaxy evolution, we find that the most massive star-forming galaxies are among the most rotation-dominated, and the most massive quiescent galaxies among the least rotation-dominated galaxies. These measurements set a new benchmark for studying galaxy evolution, using stellar dynamical structure for galaxies at large lookback time. Together with the additional information on stellar population properties from the LEGA-C spectra, the dynamical mass and $V/\sigma$ measurements presented here create new avenues for studying galaxy evolution at large lookback time., Comment: Accepted for publication in ApJ. Data table will be published with journal article and is now available upon request

The kinematic morphology-density relation of galaxies is normally attributed to a changing distribution of galaxy stellar masses with the local environment. However, earlier studies were largely focused on slow rotators; the dynamical properties of the overall population in relation to environment have received less attention. We use the SAMI Galaxy Survey to investigate the dynamical properties of $\sim$1800 early and late-type galaxies with $\log(M_*/M_{\odot})>9.5$ as a function of mean environmental overdensity ($\Sigma_{5}$) and their rank within a group or cluster. By classifying galaxies into fast and slow rotators, at fixed stellar mass above $\log(M_*/M_{\odot})>10.5$, we detect a higher fraction ($\sim3.4\sigma$) of slow rotators for group and cluster centrals and satellites as compared to isolated-central galaxies. Focusing on the fast-rotator population, we also detect a significant correlation between galaxy kinematics and their stellar mass as well as the environment they are in. Specifically, by using inclination-corrected or intrinsic $\lambda_{R_e}$ values, we find that, at fixed mass, satellite galaxies on average have the lowest $\lambda_{\,R_e,intr}$, isolated-central galaxies have the highest $\lambda_{\,R_e,intr}$, and group and cluster centrals lie in between. Similarly, galaxies in high-density environments have lower mean $\lambda_{\,R_e,intr}$ values as compared to galaxies at low environmental density. However, at fixed $\Sigma_{5}$, the mean $\lambda_{\,R_e,intr}$ differences for low and high-mass galaxies are of similar magnitude as when varying $\Sigma_{5}$ {($\Delta \lambda_{\,R_e,intr} \sim 0.05$. Our results demonstrate that after stellar mass, environment plays a significant role in the creation of slow rotators, while for fast rotators we also detect an independent, albeit smaller, impact of mass and environment on their kinematic properties., Comment: 22 pages and 17 figures, accepted for publication in MNRAS. Abstract abridged for Arxiv. The key figures of the paper are: 6, 8, 10, and 12

We have entered a new era where integral-field spectroscopic surveys of galaxies are sufficiently large to adequately sample large-scale structure over a cosmologically significant volume. This was the primary design goal of the SAMI Galaxy Survey. Here, in Data Release 3 (DR3), we release data for the full sample of 3068 unique galaxies observed. This includes the SAMI cluster sample of 888 unique galaxies for the first time. For each galaxy, there are two primary spectral cubes covering the blue (370-570nm) and red (630-740nm) optical wavelength ranges at spectral resolving power of R=1808 and 4304 respectively. For each primary cube, we also provide three spatially binned spectral cubes and a set of standardized aperture spectra. For each galaxy, we include complete 2D maps from parameterized fitting to the emission-line and absorption-line spectral data. These maps provide information on the gas ionization and kinematics, stellar kinematics and populations, and more. All data are available online through Australian Astronomical Optics (AAO) Data Central., Accepted for publication in MNRAS. 27 pages, 21 figures. Data available at https://datacentral.org.au/ . See also http://sami-survey.org/

We study the Fundamental Plane (FP) for a volume- and luminosity-limited sample of 560 early-type galaxies from the SAMI survey. Using r-band sizes and luminosities from new Multi-Gaussian Expansion (MGE) photometric measurements, and treating luminosity as the dependent variable, the FP has coefficients a=1.294$\pm$0.039, b= 0.912$\pm$0.025, and zero-point c= 7.067$\pm$0.078. We leverage the high signal-to-noise of SAMI integral field spectroscopy, to determine how structural and stellar-population observables affect the scatter about the FP. The FP residuals correlate most strongly (8$\sigma$ significance) with luminosity-weighted simple-stellar-population (SSP) age. In contrast, the structural observables surface mass density, rotation-to-dispersion ratio, S\'ersic index and projected shape all show little or no significant correlation. We connect the FP residuals to the empirical relation between age (or stellar mass-to-light ratio $\Upsilon_\star$) and surface mass density, the best predictor of SSP age amongst parameters based on FP observables. We show that the FP residuals (anti-)correlate with the residuals of the relation between surface density and $\Upsilon_\star$. This correlation implies that part of the FP scatter is due to the broad age and $\Upsilon_\star$ distribution at any given surface mass density. Using virial mass and $\Upsilon_\star$ we construct a simulated FP and compare it to the observed FP. We find that, while the empirical relations between observed stellar population relations and FP observables are responsible for most (75%) of the FP scatter, on their own they do not explain the observed tilt of the FP away from the virial plane., Comment: 36 pages, 23 figures

We present the first comparison of observed stellar continuum spectra of high-redshift galaxies and mock galaxy spectra generated from hydrodynamical simulations. The mock spectra are produced from the IllustrisTNG TNG100 simulation combined with stellar population models and take into account dust attenuation and realistic observational effects (aperture effects and noise). We compare the simulated $D_n4000$ and EW(H$\delta$) of galaxies with $10.5 \leq \log(M_\ast/M_\odot) \leq 11.5$ at $0.6 \leq z \leq 1.0$ to the observed distributions from the LEGA-C survey. TNG100 globally reproduces the observed distributions of spectral indices, implying that the age distribution of galaxies in TNG100 is generally realistic. Yet there are small but significant differences. For old galaxies, TNG100 shows small $D_n4000$ when compared to LEGA-C, while LEGA-C galaxies have larger EW(H$\delta$) at fixed $D_n4000$. There are several possible explanations: 1) LEGA-C galaxies have overall older ages combined with small contributions (a few percent in mass) from younger ($, Comment: 17 pages, 12 figures, accepted by AJ

We explore the connection between the kinematics, structures and stellar populations of massive galaxies at $0.610.5$) galaxies that span a wide range in morphology, star formation activity and environment, and therefore is representative of the massive galaxy population at $z\sim0.8$. We find that quiescent and star-forming galaxies occupy the parameter space of the $g$-band FP differently and thus have different distributions in the dynamical mass-to-light ratio ($M_{\rm dyn}/L_g$), largely owing to differences in the stellar age and recent star formation history, and, to a lesser extent, the effects of dust attenuation. In contrast, we show that both star-forming and quiescent galaxies lie on the same mass FP at $z\sim 0.8$, with a comparable level of intrinsic scatter about the plane. We examine the variation in $M_{\rm dyn}/M_*$ through the thickness of the mass FP, finding no significant residual correlations with stellar population properties, S\'ersic index, or galaxy overdensity. Our results suggest that, at fixed size and velocity dispersion, the variations in $M_{\rm dyn}/L_g$ of massive galaxies reflect an approximately equal contribution of variations in $M_*/L_g$, and variations in the dark matter fraction or initial mass function., Comment: 32 pages, 19 figures (including appendices); accepted for publication in ApJ

Using deep rest-frame optical spectroscopy from the Large Early Galaxy Astrophysical Census (LEGA-C) survey, conducted using VIMOS on the ESO Very Large Telescope, we search for low-ionization [O ii] λ λ 3726,3729 emission in the spectra of a mass-complete sample of z ≈ 0.85 galaxies. We find that 59% of UVJ-quiescent (i.e., non-star-forming) galaxies in the sample have [O ii] emission detected above our completeness limit of 1.5 Å, and the median-stacked spectrum of the remaining sample also shows [O ii] emission. The overall fraction of sources with [O ii] above our equivalent width limit is comparable to what we find in the low-redshift universe from GAMA and MASSIVE, except perhaps at the highest stellar masses (>1011.5 M ⊙). However, stacked spectra for the individual low-equivalent-width systems uniquely indicates ubiquitous [O ii] emission in the higher-z LEGA-C sample, with typical [O ii] luminosities per unit stellar mass that are a factor of ×3 larger than the lower-z GAMA sample. Star formation at higher-z could play a role in producing the [O ii] emission, although it is unlikely to provide the bulk of the ionizing photons. More work is required to fully quantify the contributions of evolved stellar populations or active galactic nuclei to the observed spectra.

We present an overview of the Middle Ages Galaxy Properties with Integral Field Spectroscopy (MAGPI) survey, a Large Program on ESO/VLT. MAGPI is designed to study the physical drivers of galaxy transformation at a lookback time of 3-4 Gyr, during which the dynamical, morphological, and chemical properties of galaxies are predicted to evolve significantly. The survey uses new medium-deep adaptive optics aided MUSE observations of fields selected from the GAMA survey, providing a wealth of publicly available ancillary multi-wavelength data. With these data, MAGPI will map the kinematic and chemical properties of stars and ionised gas for a sample of 60 massive (> 7 x 10^10 M_Sun) central galaxies at 0.25 < z, 31 pages, 13 figures, PASA accepted

We use the Fundamental Plane (FP) to measure the redshift evolution of the dynamical mass-to-light ratio ($M_{\mathrm{dyn}}/L$) and the dynamical-to-stellar mass ratio ($M_{\mathrm{dyn}}/M_*$). Although conventionally used to study the properties of early-type galaxies, we here obtain stellar kinematic measurements from the Large Early Galaxy Astrophysics Census (LEGA-C) Survey for a sample of $\sim1400$ massive ($\log( M_*/M_\odot) >10.5$) galaxies at $0.6, Comment: 7 pages, 4 figures; accepted for publication in ApJL

We present a novel approach to measure the attenuation curves of 485 individual star-forming galaxies with M$_*$ $>$ 10$^{10}$ M$_{\odot}$ based on deep optical spectra from the VLT/VIMOS LEGA-C survey and multi-band photometry in the COSMOS field. Most importantly, we find that the attenuation curves in the rest-frame $3000-4500$A range are typically almost twice as steep as the Milky Way, LMC, SMC, and Calzetti attenuation curves, which is in agreement with recent studies of the integrated light of present-day galaxies. The attenuation at $4500$A and the slope strongly correlate with the galaxy inclination: face-on galaxies show less attenuation and steeper curves compared to edge-on galaxies, suggesting that geometric effects dominate observed variations in attenuation. Our new method produces $2175$A UV bump detections for 260 individual galaxies. Even though obvious correlations between UV bump strength and global galaxy properties are absent, strong UV bumps are most often seen in face-on, lower-mass galaxies (10 $, Comment: 15 pages, 10 figures, 1 table. Accepted for publication in The Astrophysical Journal

We use deep, spatially resolved spectroscopy from the LEGA-C Survey to study radial variations in the stellar population of 17 spectroscopically-selected post-starburst (PSB) galaxies. We use spectral fitting to measure two Lick indices, $H{\delta}_A$ and $Fe4383$, and find that, on average, PSB galaxies have radially decreasing $H{\delta}_A$ and increasing $Fe4383$ profiles. In contrast, a control sample of quiescent, non-PSB galaxies in the same mass range shows outwardly increasing $H{\delta}_A$ and decreasing $Fe4383$. The observed gradients are weak ($\approx-0.2$ \r{A}/$R_e$), mainly due to seeing convolution. A two-SSP model suggests intrinsic gradients are as strong as observed in local PSB galaxies ($\approx -0.8$ \r{A}$/R_e$). We interpret these results in terms of inside-out growth (for the bulk of the quiescent population) vs star formation occurring last in the centre (for PSB galaxies). At $z\approx0.8$, central starbursts are often the result of gas-rich mergers, as evidenced by the high fraction of PSB galaxies with disturbed morphologies and tidal features (40%). Our results provide additional evidence for multiple paths to quiescence: a standard path, associated with inside-out disc formation and with gradually decreasing star-formation activity, without fundamental structural transformation, and a fast path, associated with centrally-concentrated starbursts, leaving an inverse age gradient and smaller half-light radius., Comment: 18 pages, 9 figures

In this letter, we investigate the impact of environment on integrated and spatially-resolved stellar kinematics of a sample of massive, quiescent galaxies at intermediate redshift ($0.6, Comment: 10 pages, 5 figures, submitted to ApJ Letters

We analyze the colors and sizes of 32 quiescent (UVJ-selected) galaxies with strong Balmer absorption ($\mbox{EW}(H\delta) \geq 4$\AA) at $z\sim0.8$ drawn from DR2 of the LEGA-C survey to test the hypothesis that these galaxies experienced compact, central starbursts before quenching. These recently quenched galaxies, usually referred to as post-starburst galaxies, span a wide range of colors and we find a clear correlation between color and half-light radius, such that bluer galaxies are smaller. We build simple toy models to explain this correlation: a normal star-forming disk plus a central, compact starburst component. Bursts with exponential decay timescale of $\sim$~100 Myr that produce $\sim10\%$ to more than 100\% of the pre-existing masses can reproduce the observed correlation. More significant bursts also produce bluer and smaller descendants. Our findings imply that when galaxies shut down star formation rapidly, they generally had experienced compact, starburst events and that the large, observed spread in sizes and colors mostly reflects a variety of burst strengths. Recently quenched galaxies should have younger stellar ages in the centers; multi-wavelength data with high spatial resolution are required to reveal the age gradient. Highly dissipative processes should be responsible for this type of formation history. While determining the mechanisms for individual galaxies is challenging, some recently quenched galaxies show signs of gravitational interactions, suggesting that mergers are likely an important mechanism in triggering the rapid shut-down of star-formation activities at $z\sim0.8$., Comment: 16 pages, 8 figures, 1 table, accepted by ApJ

Stellar population parameters correlate with a range of galaxy properties, but it is unclear which relations are causal and which are the result of another underlying trend. In this series, we quantitatively compare trends between stellar population properties and galaxy structural parameters in order to determine which relations are intrinsically tighter, and are therefore more likely to reflect a causal relation. Specifically, we focus on the galaxy structural parameters of mass $M$, gravitational potential $\Phi\sim M/R_e$, and surface mass density $\Sigma\sim M/R_e^2$. In Barone et al. (2018) we found that for early-type galaxies the age-$\Sigma$ and [Z/H]-$\Phi$ relations show the least intrinsic scatter as well as the least residual trend with galaxy size. In this work we study the ages and metallicities measured from full spectral fitting of 2085 star-forming galaxies from the SDSS Legacy Survey, selected so all galaxies in the sample are probed to one effective radius. As with the trends found in early-type galaxies, we find that in star-forming galaxies age correlates best with stellar surface mass density, and [Z/H] correlates best with gravitational potential. We discuss multiple mechanisms that could lead to these scaling relations. For the [Z/H]--$\Phi$ relation we conclude that gravitational potential is the primary regulator of metallicity, via its relation to the gas escape velocity. The age--$\Sigma$ relation is consistent with compact galaxies forming earlier, as higher gas fractions in the early universe cause old galaxies to form more compactly during their in-situ formation phase, and may be reinforced by compactness-related quenching mechanisms., Comment: Accepted for publication in ApJ. 20 pages, 9 figures, 1 table

Galaxy evolution is driven by a variety of physical processes that are predicted to proceed at different rates for different dark matter haloes and environments across cosmic times. A record of this evolution is preserved in galaxy stellar populations, which we can access using absorption-line spectroscopy. Here we explore the large LEGA-C survey (DR3) to investigate the role of the environment and stellar mass on stellar populations at z ∼ 0.6–1 in the COSMOS field. Leveraging the statistical power and depth of LEGA-C, we reveal significant gradients in D n 4000 and Hδ equivalent widths (EWs) distributions over the stellar mass versus environment 2D spaces for the massive galaxy population (M > 1010 M ⊙) at z ∼ 0.6–1.0. D n 4000 and Hδ EWs primarily depend on stellar mass, but they also depend on environment at fixed stellar mass. By splitting the sample into centrals and satellites, and in terms of star-forming galaxies and quiescent galaxies, we reveal that the significant environmental trends of D n 4000 and Hδ EW, when controlling for stellar mass, are driven by quiescent galaxies. Regardless of being centrals or satellites, star-forming galaxies reveal D n 4000 and Hδ EWs, which depend strongly on their stellar mass and are completely independent of the environment at 0.6 < z < 1.0. The environmental trends seen for satellite galaxies are fully driven by the trends that hold only for quiescent galaxies, combined with the strong environmental dependency of the quiescent fraction at fixed stellar mass. Our results are consistent with recent predictions from simulations that point toward massive galaxies forming first in overdensities or the most compact dark matter haloes.

We present a comparative study of the relation between the aperture-based gas-phase metallicity and three structural parameters of star-forming galaxies: mass ($\mathrm{M \equiv M_*}$), average potential ($\Phi \equiv \mathrm{M_*/R_e}$) and average surface mass density ($\Sigma \equiv \mathrm{M_*/R_e^2}$; where $\mathrm{R_e}$ is the effective radius). We use a volume-limited sample drawn from the publicly available SDSS DR7, and base our analysis on aperture-matched sampling by selecting sets of galaxies where the SDSS fibre probes a fixed fraction of $\mathrm{R_e}$. We find that between 0.5 and 1.5 $\mathrm{R_e}$, the gas-phase metallicity correlates more tightly with $\Phi$ than with either $\mathrm{M}$ or $\Sigma$, in that for all aperture-matched samples, the potential-metallicity relation has (i) less scatter, (ii) higher Spearman rank correlation coefficient and (iii) less residual trend with $\mathrm{R_e}$ than either the mass-metallicity relation and the average surface density-metallicity relation. Our result is broadly consistent with the current models of gas enrichment and metal loss. However, a more natural explanation for our findings is a local relation between the gas-phase metallicity and escape velocity., Comment: Accepted by MNRAS; 17 pages, 11 figures, 1 table

We investigate the stellar population properties of bulges and disks separately for 34 S0s using integral field spectroscopy from the Calar Alto Legacy Integral Field Area survey. The spatially resolved stellar age and metallicity of bulge and disk components have been simultaneously estimated using the penalized pixel fitting method with photometrically defined weights for the two components. We find a tight correlation between age and metallicity for bulges, while the relation for disks has a larger scatter than that of bulges. This implies that the star formation histories of the disks are more complicated than those of the bulges. Bulges of the high-mass S0s are mostly comparable in metallicity, while bulges appear to be systematically more metal-rich than disks for the low-mass S0s. The ages of bulges and disks in the high-mass S0s appear to increase with local density. The bulge ages of the low-mass S0s also increases with local density, but such a trend is not clear in the disk ages of low-mass S0s. In addition, the age difference between bulge and disk components (delta Age) tends to increase with local density, both for the high-mass and low-mass S0s. The high-mass S0s have systematically higher delta Age than the low-mass S0s at given local density. Our results indicate that the stellar mass significantly influences the evolution of S0 galaxies, but the environment also plays an important role in determining the evolution of bulges and disks at given stellar mass., Comment: 16 pages, 7 figures, 2 tables, Accepted for publication in ApJ

We present the third and final data release of the Large Early Galaxy Astrophysics Census (LEGA-C), an ESO/VLT public spectroscopic survey targeting $0.6 < z < 1.0$, Ks-selected galaxies. The data release contains 3528 spectra with measured stellar velocity dispersions and stellar population properties, a 25-fold increase in sample size compared to previous work. This $K_s$-selected sample probes the galaxy population down to $\sim0.3 L^*$, for all colors and morphological types. Along with the spectra we publish a value-added catalog with stellar and ionized gas velocity dispersions, stellar absorption line indices, emission line fluxes and equivalent widths, complemented with structural parameters measured from HST/ACS imaging. With its combination of high precision and large sample size, LEGA-C provides a new benchmark for galaxy evolution studies., Comment: Accepted for publication in ApJS. Data available at http://archive.eso.org/cms/eso-archive-news/Third-and-final-release-of-the-Large-Early-Galaxy-Census-LEGA-C-Spectroscopic-Public-Survey-published.html or https://users.ugent.be/\string~avdrwel/research.html\#legac

The existence of a kinematic morphology-density relation remains uncertain, and instead stellar mass appears the more dominant driver of galaxy kinematics. We investigate the dependence of the stellar spin parameter proxy $\lambda_{R_e}$ on environment using a marked cross-correlation method with data from the SAMI Galaxy Survey. Our sample contains 710 galaxies with spatially resolved stellar velocity and velocity dispersion measurements. By utilising the highly complete spectroscopic data from the GAMA survey, we calculate marked cross-correlation functions for SAMI galaxies using a pair count estimator and marks based on stellar mass and $\lambda_{R_e}$. We detect an anti-correlation of stellar kinematics with environment at the 3.2$\sigma$ level, such that galaxies with low $\lambda_{R_e}$ values are preferably located in denser galaxy environments. However, a significant correlation between stellar mass and environment is also found (correlation at 2.4$\sigma$), as found in previous works. We compare these results to mock-observations from the cosmological EAGLE simulations, where we find a similar significant $\lambda_{R_e}$ anti-correlation with environment, and a mass and environment correlation. We demonstrate that the environmental correlation of $\lambda_{R_e}$ is not caused by the mass-environment relation. The significant relationship between $\lambda_{R_e}$ and environment remains when we exclude slow rotators. The signals in SAMI and EAGLE are strongest on small scales (10-100 kpc) as expected from galaxy interactions and mergers. Our work demonstrates that the technique of marked correlation functions is an effective tool for detecting the relationship between $\lambda_{R_e}$ and environment., Comment: 10 pages, 4 figures, 1 table, accepted in to Astrophysical Journal

Using the stellar kinematic maps and ancillary imaging data from the Sydney AAO Multi Integral field (SAMI) Galaxy Survey, the intrinsic shape of kinematically-selected samples of galaxies is inferred. We implement an efficient and optimised algorithm to fit the intrinsic shape of galaxies using an established method to simultaneously invert the distributions of apparent ellipticities and kinematic misalignments. The algorithm output compares favourably with previous studies of the intrinsic shape of galaxies based on imaging alone and our re-analysis of the ATLAS3D data. Our results indicate that most galaxies are oblate axisymmetric. We show empirically that the intrinsic shape of galaxies varies as a function of their rotational support as measured by the "spin" parameter proxy Lambda_Re. In particular, low spin systems have a higher occurrence of triaxiality, while high spin systems are more intrinsically flattened and axisymmetric. The intrinsic shape of galaxies is linked to their formation and merger histories. Galaxies with high spin values have intrinsic shapes consistent with dissipational minor mergers, while the intrinsic shape of low-spin systems is consistent with dissipationless multi-merger assembly histories. This range in assembly histories inferred from intrinsic shapes is broadly consistent with expectations from cosmological simulations., Comment: 15 pages, 11 figures, MNRAS in print

We use data from the Sydney-AAO Multi-object Integral-field spectroscopy (SAMI) Galaxy Survey to study the dynamical scaling relation between galaxy stellar mass $M_*$ and the general kinematic parameter $S_K = \sqrt{K V_{rot}^2 + \sigma^2}$ that combines rotation velocity $V_{rot}$ and velocity dispersion $\sigma$. We show that the $\log M_* - \log S_K$ relation: (1)~is linear above limits set by properties of the samples and observations; (2)~has slightly different slope when derived from stellar or gas kinematic measurements; (3)~applies to both early-type and late-type galaxies and has smaller scatter than either the Tully-Fisher relation ($\log M_* - \log V_{rot}$) for late types or the Faber-Jackson relation ($\log M_* - \log\sigma$) for early types; and (4)~has scatter that is only weakly sensitive to the value of $K$, with minimum scatter for $K$ in the range 0.4 and 0.7. We compare $S_K$ to the aperture second moment (the `aperture velocity dispersion') measured from the integrated spectrum within a 3-arcsecond radius aperture ($\sigma_{3^{\prime\prime}}$). We find that while $S_{K}$ and $\sigma_{3^{\prime\prime}}$ are in general tightly correlated, the $\log M_* - \log S_K$ relation has less scatter than the $\log M_* - \log \sigma_{3^{\prime\prime}}$ relation., Comment: 14 pages, 8 figures, Accepted 2019 May 22. Received 2019 May 18; in original form 2019 January 6

We present the second major release of data from the SAMI Galaxy Survey. Data Release Two includes data for 1559 galaxies, about 50% of the full survey. Galaxies included have a redshift range 0.004 < z < 0.113 and a large stellar mass range 7.5 < log (M_star/M_sun) < 11.6. The core data for each galaxy consist of two primary spectral cubes covering the blue and red optical wavelength ranges. For each primary cube we also provide three spatially binned spectral cubes and a set of standardised aperture spectra. For each core data product we provide a set of value-added data products. This includes all emission line value-added products from Data Release One, expanded to the larger sample. In addition we include stellar kinematic and stellar population value-added products derived from absorption line measurements. The data are provided online through Australian Astronomical Optics' Data Central. We illustrate the potential of this release by presenting the distribution of ~350,000 stellar velocity dispersion measurements from individual spaxels as a function of R/R_e, divided in four galaxy mass bins. In the highest stellar mass bin (log (M_star/M_sun)>11), the velocity dispersion strongly increases towards the centre, whereas below log (M_star/M_sun), 22 pages, 14 figures. Accepted for publication in MNRAS. See the SAMI Data Release 2 website (https://sami-survey.org/abdr) for current status. The data can be accessed via Australian Astronomical Optics' Data Central service (https://datacentral.org.au/)

We present a comparison of the observed, spatially integrated stellar and ionized gas velocity dispersions of $\sim1000$ massive ($\log M_{\star}/M_{\odot}\gtrsim\,10.3$) galaxies in the Large Early Galaxy Astrophysics Census (LEGA-C) survey at $0.6\lesssim\,z\lesssim1.0$. The high $S/N\sim20{\rm\AA^{-1}}$ afforded by 20 hour VLT/VIMOS spectra allows for joint modeling of the stellar continuum and emission lines in all galaxies, spanning the full range of galaxy colors and morphologies. These observed integrated velocity dispersions (denoted as $\sigma'_{g, int}$ and $\sigma'_{\star, int}$) are related to the intrinsic velocity dispersions of ionized gas or stars, but also include rotational motions through beam smearing and spectral extraction. We find good average agreement between observed velocity dispersions, with $\langle\log(\sigma'_{g, int}/\sigma'_{\star, int})\rangle=-0.003$. This result does not depend strongly on stellar population, structural properties, or alignment with respect to the slit. However, in all regimes we find significant scatter between $\sigma'_{g, int}$ and $\sigma'_{\star, int}$, with an overall scatter of 0.13 dex of which 0.05 dex is due to observational uncertainties. For an individual galaxy, the scatter between $\sigma'_{g, int}$ and $\sigma'_{\star, int}$ translates to an additional uncertainty of $\sim0.24\rm{dex}$ on dynamical mass derived from $\sigma'_{g, int}$, on top of measurement errors and uncertainties from Virial constant or size estimates. We measure the $z\sim0.8$ stellar mass Faber-Jackson relation and demonstrate that emission line widths can be used to measure scaling relations. However, these relations will exhibit increased scatter and slopes that are artificially steepened by selecting on subsets of galaxies with progressively brighter emission lines., Comment: 9 pages, 5 figures, Accepted for publication in ApJ Letters

In order to determine the causes of kinematic asymmetry in the H$\alpha$ gas in the SAMI Galaxy Survey sample, we investigate the comparative influences of environment and intrinsic properties of galaxies on perturbation. We use spatially resolved H$\alpha$ velocity fields from the SAMI Galaxy Survey to quantify kinematic asymmetry ($\overline{v_{asym}}$) in nearby galaxies and environmental and stellar mass data from the GAMA survey. {We find that local environment, measured as distance to nearest neighbour, is inversely correlated with kinematic asymmetry for galaxies with $\mathrm{\log(M_*/M_\odot)}>10.0$, but there is no significant correlation for galaxies with $\mathrm{\log(M_*/M_\odot)}, Comment: 15 pages, 20 figures

We present the SAMI Pilot Survey, consisting of integral field spectroscopy of 106 galaxies across three galaxy clusters, Abell 85, Abell 168 and Abell 2399. The galaxies were selected by absolute magnitude to have $M_r, Comment: 19 pages, 15 figures

We present an analysis of the global stellar populations of galaxies in the SAMI Galaxy Survey. Our sample consists of 1319 galaxies spanning four orders of magnitude in stellar mass and includes all morphologies and environments. We derive luminosity-weighted, single stellar population equivalent stellar ages, metallicities and alpha enhancements from spectra integrated within one effective radius apertures. Variations in galaxy size explain the majority of the scatter in the age--mass and metallicity--mass relations. Stellar populations vary systematically in the plane of galaxy size and stellar mass, such that galaxies with high stellar surface mass density are older, more metal-rich and alpha-enhanced than less dense galaxies. Galaxies with high surface mass densities have a very narrow range of metallicities, however, at fixed mass, the spread in metallicity increases substantially with increasing galaxy size (decreasing density). We identify residual correlations with morphology and environment. At fixed mass and size, galaxies with late-type morphologies, small bulges and low Sersic n are younger than early-type, high n, high bulge-to-total galaxies. Age and metallicity both show small residual correlations with environment; at fixed mass and size, galaxies in denser environments or more massive halos are older and somewhat more metal rich than those in less dense environments. We connect these trends to evolutionary tracks within the size--mass plane., Comment: 25 pages, 18 figures, MNRAS in press Corrected typo in author list

We investigate the Tully–Fisher relation (TFR) for a morphologically and kinematically diverse sample of galaxies from the Sydney-AAO Multi-object Integral field spectrograph (SAMI) Galaxy Survey using two-dimensional spatially resolved H α velocity maps and find a well-defined relation across the stellar mass range of 8.0 < log (M*/M⊙) < 11.5. We use an adaptation of kinemetry to parametrize the kinematic H α asymmetry of all galaxies in the sample, and find a correlation between scatter (i.e. residuals off the TFR) and asymmetry. This effect is pronounced at low stellar mass, corresponding to the inverse relationship between stellar mass and kinematic asymmetry found in previous work. For galaxies with log (M*/M⊙) < 9.5, 25 ± 3 per cent are scattered below the root mean square (RMS) of the TFR, whereas for galaxies with log (M*/M⊙) > 9.5 the fraction is 10 ± 1 per cent. We use ‘simulated slits’ to directly compare our results with those from long slit spectroscopy and find that aligning slits with the photometric, rather than the kinematic, position angle, increases global scatter below the TFR. Further, kinematic asymmetry is correlated with misalignment between the photometric and kinematic position angles. This work demonstrates the value of 2D spatially resolved kinematics for accurate TFR studies; integral field spectroscopy reduces the underestimation of rotation velocity that can occur from slit positioning off the kinematic axis.

The fraction of galaxies supported by internal rotation compared to galaxies stabilized by internal pressure provides a strong constraint on galaxy formation models. In integral field spectroscopy surveys, this fraction is biased because survey instruments typically only trace the inner parts of the most massive galaxies. We present aperture corrections for the two most widely used stellar kinematic quantities $V/\sigma$ and $\lambda_{R}$. Our demonstration involves integral field data from the SAMI Galaxy Survey and the ATLAS$^{\rm{3D}}$ Survey. We find a tight relation for both $V/\sigma$ and $\lambda_{R}$ when measured in different apertures that can be used as a linear transformation as a function of radius, i.e., a first-order aperture correction. We find that $V/\sigma$ and $\lambda_{R}$ radial growth curves are well approximated by second order polynomials. By only fitting the inner profile (0.5$R_{\rm{e}}$), we successfully recover the profile out to one $R_{\rm{e}}$ if a constraint between the linear and quadratic parameter in the fit is applied. However, the aperture corrections for $V/\sigma$ and $\lambda_{R}$ derived by extrapolating the profiles perform as well as applying a first-order correction. With our aperture-corrected $\lambda_{R}$ measurements, we find that the fraction of slow rotating galaxies increases with stellar mass. For galaxies with $\log M_{*}/M_{\odot}>$ 11, the fraction of slow rotators is $35.9\pm4.3$ percent, but is underestimated if galaxies without coverage beyond one $R_{\rm{e}}$ are not included in the sample ($24.2\pm5.3$ percent). With measurements out to the largest aperture radius the slow rotator fraction is similar as compared to using aperture corrected values ($38.3\pm4.4$ percent). Thus, aperture effects can significantly bias stellar kinematic IFS studies, but this bias can now be removed with the method outlined here., Comment: Accepted for Publication in the Monthly Notices of the Royal Astronomical Society. 16 pages and 11 figures. The key figures of the paper are: 1, 4, 9, and 10

We examine the kinematic morphology of early-type galaxies (ETGs) in eight galaxy clusters in the Sydney-AAO Multi-object Integral field spectrograph (SAMI) Galaxy Survey. The clusters cover a mass range of 14.2, Comment: Accepted by ApJ 15 June 2017

Recent cosmological hydrodynamical simulations suggest that integral field spectroscopy can connect the high-order stellar kinematic moments h3 (~skewness) and h4 (~kurtosis) in galaxies to their cosmological assembly history. Here, we assess these results by measuring the stellar kinematics on a sample of 315 galaxies, without a morphological selection, using 2D integral field data from the SAMI Galaxy Survey. A proxy for the spin parameter ($\lambda_{R_e}$) and ellipticity ($\epsilon_e$) are used to separate fast and slow rotators; there exists a good correspondence to regular and non-regular rotators, respectively, as also seen in earlier studies. We confirm that regular rotators show a strong h3 versus $V/\sigma$ anti-correlation, whereas quasi-regular and non-regular rotators show a more vertical relation in h3 and $V/\sigma$. Motivated by recent cosmological simulations, we develop an alternative approach to kinematically classify galaxies from their individual h3 versus $V/\sigma$ signatures. We identify five classes of high-order stellar kinematic signatures using Gaussian mixture models. Class 1 corresponds to slow rotators, whereas Classes 2-5 correspond to fast rotators. We find that galaxies with similar $\lambda_{R_e}-\epsilon_e$ values can show distinctly different h3-$V/\sigma$ signatures. Class 5 objects are previously unidentified fast rotators that show a weak h3 versus $V/\sigma$ anti-correlation. These objects are predicted to be disk-less galaxies formed by gas-poor mergers. From morphological examination, however, there is evidence for large stellar disks. Instead, Class 5 objects are more likely disturbed galaxies, have counter-rotating bulges, or bars in edge-on galaxies. Finally, we interpret the strong anti-correlation in h3 versus $V/\sigma$ as evidence for disks in most fast rotators, suggesting a dearth of gas-poor mergers among fast rotators., Comment: Accepted for Publication in The Astrophysical Journal. 35 pages and 30 figures, abstract abridged for arXiv submission. The key figures of the paper are: 7, 11, 12 , and 14

We present the first major release of data from the SAMI Galaxy Survey. This data release focuses on the emission-line physics of galaxies. Data Release One includes data for 772 galaxies, about 20% of the full survey. Galaxies included have the redshift range 0.004 < z < 0.092, a large mass range (7.6 < log(Mstellar/M$_\odot$) < 11.6), and star-formation rates of 10^-4 to 10^1\ M$_\odot$/yr. For each galaxy, we include two spectral cubes and a set of spatially resolved 2D maps: single- and multi-component emission-line fits (with dust extinction corrections for strong lines), local dust extinction and star-formation rate. Calibration of the fibre throughputs, fluxes and differential-atmospheric-refraction has been improved over the Early Data Release. The data have average spatial resolution of 2.16 arcsec (FWHM) over the 15~arcsec diameter field of view and spectral (kinematic) resolution R=4263 (sigma=30km/s) around Halpha. The relative flux calibration is better than 5\% and absolute flux calibration better than $\pm0.22$~mag, with the latter estimate limited by galaxy photometry. The data are presented online through the Australian Astronomical Observatory's Data Central., Submitted to MNRAS. SAMI DR1 data products available from http://datacentral.aao.gov.au/asvo/surveys/sami/

We present a photometric analysis of 65 galaxies in the rich cluster Abell 1689 at $z=0.183$, using the Hubble Space Telescope Advanced Camera for Surveys archive images in the rest-frame $V$-band. We perform two-dimensional multi-component photometric decomposition of each galaxy adopting different models of the surface-brightness distribution. We present an accurate morphological classification for each of the sample galaxies. For 50 early-type galaxies, we fit both a de Vaucouleurs and S\'ersic law; S0s are modelled by also including a disc component described by an exponential law. Bars of SB0s are described by the profile of a Ferrers ellipsoid. For the 15 spirals, we model a S\'ersic bulge, exponential disc, and, when required, a Ferrers bar component. We derive the Fundamental Plane by fitting 40 early-type galaxies in the sample, using different surface-brightness distributions. We find that the tightest plane is that derived by S\'ersic bulges. We find that bulges of spirals lie on the same relation. The Fundamental Plane is better defined by the bulges alone rather than the entire galaxies. Comparison with local samples shows both an offset and rotation in the Fundamental Plane of Abell 1689., Comment: 53 pages, 71 figures, MNRAS in press