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In Galaxy And Mass Assembly Data Release 4 (GAMA DR4), we make available our full spectroscopic redshift sample. This includes 248682 galaxy spectra, and, in combination with earlier surveys, results in 330542 redshifts across five sky regions covering ~250deg^2. The redshift density, is the highest available over such a sustained area, has exceptionally high completeness (95 per cent to r_KIDS=19.65mag), and is well suited for the study of galaxy mergers, galaxy groups, and the low redshift (z<0.25) galaxy population. DR4 includes 32 value-added tables or Data Management Units (DMUs) that provide a number of measured and derived data products including GALEX, ESO KiDS, ESO VIKING, WISE and Herschel Space Observatory imaging. Within this release, we provide visual morphologies for 15330 galaxies to z<0.08, photometric redshift estimates for all 18million objects to r_KIDS~25mag, and stellar velocity dispersions for 111830 galaxies. We conclude by deriving the total galaxy stellar mass function (GSMF) and its sub-division by morphological class (elliptical, compact-bulge and disc, diffuse-bulge and disc, and disc only). This extends our previous measurement of the total GSMF down to 10^6.75 M_sol h^-2_70 and we find a total stellar mass density of rho_*=(2.97+/-0.04)x10^8 M_sol h_70 Mpc^-3 or Omega_*=(2.17+/-0.03)x10^-3 h^-1_70. We conclude that at z<0.1, the Universe has converted 4.9+/-0.1 per cent of the baryonic mass implied by Big Bang Nucleosynthesis into stars that are gravitationally bound within the galaxy population., Comment: Accepted for publication in MNRAS. GAMA Data Release 4 is available at: http://www.gama-survey.org/dr4/

Context. The accurate classification of hundreds of thousands of galaxies observed in modern deep surveys is imperative if we want to understand the universe and its evolution. Aims. Here, we report the use of machine learning techniques to classify early- and late-type galaxies in the OTELO and COSMOS databases using optical and infrared photometry and available shape parameters: either the Sersic index or the concentration index. Methods. We used three classification methods for the OTELO database: 1) u-r color separation , 2) linear discriminant analysis using u-r and a shape parameter classification, and 3) a deep neural network using the r magnitude, several colors, and a shape parameter. We analyzed the performance of each method by sample bootstrapping and tested the performance of our neural network architecture using COSMOS data. Results. The accuracy achieved by the deep neural network is greater than that of the other classification methods, and it can also operate with missing data. Our neural network architecture is able to classify both OTELO and COSMOS datasets regardless of small differences in the photometric bands used in each catalog. Conclusions. In this study we show that the use of deep neural networks is a robust method to mine the cataloged data, Comment: 20 pages, 10 tables, 14 figures, Astronomy and Astrophysics (in press)

The OTELO survey is a very deep, blind exploration of a selected region of the Extended Groth Strip and is designed for finding emission-line sources (ELSs). The survey design, observations, data reduction, astrometry, and photometry, as well as the correlation with ancillary data used to obtain a final catalogue, including photo-z estimates and a preliminary selection of ELS, were described in a previous contribution. Here, we aim to determine the main properties and luminosity function (LF) of the [O III] ELS sample of OTELO as a scientific demonstration of its capabilities, advantages, and complementarity with respect to other surveys. The selection and analysis procedures of ELS candidates obtained using tunable filter (TF) pseudo-spectra are described. We performed simulations in the parameter space of the survey to obtain emission-line detection probabilities. Relevant characteristics of [O III] emitters and the LF([O III]), including the main selection biases and uncertainties, are presented. A total of 184 sources were confirmed as [O III] emitters at a mean redshift z=0.83. The minimum detectable line flux and equivalent width (EW) in this ELS sample are $\sim$5 $\times$ 10$^{-19}$ erg s$^{-1}$ cm$^{2}$ and $\sim$6 \AA, respectively. We are able to constrain the faint-end slope ($\alpha = -1.03\pm0.08$) of the observed LF([O III]) at z=0.83. This LF reaches values that are approximately ten times lower than those from other surveys. The vast majority (84\%) of the morphologically classified [O III] ELSs are disc-like sources, and 87\% of this sample is comprised of galaxies with stellar masses of M$_\star$ $<$ 10$^{10}$ M$_{\odot}$., Comment: v1: 16 pages, 6 figures. Accepted in Astronomy \& Astrophysics. v2: Author added in metadata

The evolution of galaxies through cosmic time is studied observationally by means of extragalactic surveys. The OTELO survey aims to provide the deepest narrow-band survey to date in terms of minimum detectable flux and emission line equivalent width in order to detect the faintest extragalactic emission line systems. In this way, OTELO data will complements other broad-band, narrow-band, and spectroscopic surveys. The red tunable filter of the OSIRIS instrument on the 10.4 m Gran Telescopio Canarias (GTC) is used to scan a spectral window centred at $9175 \AA$, which is free from strong sky emission lines, with a sampling interval of $6 \AA$ and a bandwidth of $12 \AA$ in the most deeply explored Extended Groth Strip region. Careful data reduction using improved techniques for sky ring subtraction, accurate astrometry, photometric calibration, and source extraction enables us to compile the OTELO catalogue. This catalogue is complemented with ancillary data ranging from deep X-ray to far-infrared, including high resolution HST images, which allow us to segregate the different types of targets, derive precise photometric redshifts, and obtain the morphological classification of the extragalactic objects detected. The OTELO multi-wavelength catalogue contains 11237 entries and is 50\% complete at AB magnitude 26.38. Of these sources, 6600 have photometric redshifts with an uncertainty $z_{phot}$ better than $0.2 (1+z_{phot})$. A total of 4336 of these sources correspond to preliminary emission line candidates, which are complemented by 81 candidate stars and 483 sources that qualify as absorption line systems. The OTELO survey products were released to the public on 2019., Comment: v1: 29 pages, 29 figures. Published in Astronomy \& Astrophysics. v2: author's affiliation and final statement in Abstract updated

We present the final distance measurements for the 2MASS Tully-Fisher (2MTF) survey. The final 2MTF catalogue contains 2,062 nearby spiral galaxies in the CMB frame velocity range of 600 km s$^{-1}$ $< cz < 10,000$ km s$^{-1}$ with a mean velocity of 4,805 km s$^{-1}$. The main update in this release is the replacement of some archival HI data with newer ALFALFA data. Using the 2MTF template relation, we calculate the distances and peculiar velocities of all 2MTF galaxies. The mean uncertainties of the linear distance measurements are around 22\% in all three infrared bands. 2MTF measurements agree well with the distances from the Cosmicflows-3 compilation, which contains 1,117 common galaxies, including 28 with SNIa distance measurements. Using distances estimated from the `3-bands combined' 2MTF sample and a $\chi^2$ minimization method, we find best-fit bulk flow amplitudes of $308 \pm 26$ km s$^{-1}$, $318 \pm 29$ km s$^{-1}$, and $286 \pm 25$ km s$^{-1}$ at depths of $R_I = $ 20, 30 and 40 $h^{-1}{\rm Mpc}$, respectively, which is consistent with the $\Lambda$CDM model and with previous 2MTF results with different estimation techniques and a preliminary catalogue., Comment: 8 pages, 6 figures, 2 tables, accepted for publication in MNRAS

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., Comment: Submitted to MNRAS. SAMI DR1 data products available from http://datacentral.aao.gov.au/asvo/surveys/sami/

We present measurements of the velocity power spectrum and constraints on the growth rate of structure $f\sigma_{8}$, at redshift zero, using the peculiar motions of 2,062 galaxies in the completed 2MASS Tully-Fisher survey (2MTF). To accomplish this we introduce a model for fitting the velocity power spectrum including the effects of non-linear Redshift Space Distortions (RSD), allowing us to recover unbiased fits down to scales $k=0.2\,h\,{\rm Mpc}^{-1}$ without the need to smooth or grid the data. Our fitting methods are validated using a set of simulated 2MTF surveys. Using these simulations we also identify that the Gaussian distributed estimator for peculiar velocities of \cite{Watkins2015} is suitable for measuring the velocity power spectrum, but sub-optimal for the 2MTF data compared to using magnitude fluctuations $\delta m$, and that, whilst our fits are robust to a change in fiducial cosmology, future peculiar velocity surveys with more constraining power may have to marginalise over this. We obtain \textit{scale-dependent} constraints on the growth rate of structure in two bins, finding $f\sigma_{8} = [0.55^{+0.16}_{-0.13},0.40^{+0.16}_{-0.17}]$ in the ranges $k = [0.007-0.055, 0.55-0.150]\,h\,{\rm Mpc}^{-1}$. We also find consistent results using four bins. Assuming scale-\textit{independence} we find a value $f\sigma_{8} = 0.51^{+0.09}_{-0.08}$, a $\sim16\%$ measurement of the growth rate. Performing a consistency check of General Relativity (GR) and combining our results with CMB data only we find $\gamma = 0.45^{+0.10}_{-0.11}$, a remarkable constraint considering the small number of galaxies. All of our results are completely independent of the effects of galaxy bias, and fully consistent with the predictions of GR (scale-independent $f\sigma_{8}$ and $\gamma\approx0.55$)., Comment: 18 pages, 14 figures, 3 tables. Accepted for publication in MNRAS

Taipan is a multi-object spectroscopic galaxy survey starting in 2017 that will cover 2pi steradians over the southern sky, and obtain optical spectra for about two million galaxies out to z<0.4. Taipan will use the newly-refurbished 1.2m UK Schmidt Telescope at Siding Spring Observatory with the new TAIPAN instrument, which includes an innovative 'Starbugs' positioning system capable of rapidly and simultaneously deploying up to 150 spectroscopic fibres (and up to 300 with a proposed upgrade) over the 6-deg diameter focal plane, and a purpose-built spectrograph operating from 370 to 870nm with resolving power R>2000. The main scientific goals of Taipan are: (i) to measure the distance scale of the Universe (primarily governed by the local expansion rate, H_0) to 1% precision, and the structure growth rate of structure to 5%; (ii) to make the most extensive map yet constructed of the mass distribution and motions in the local Universe, using peculiar velocities based on improved Fundamental Plane distances, which will enable sensitive tests of gravitational physics; and (iii) to deliver a legacy sample of low-redshift galaxies as a unique laboratory for studying galaxy evolution as a function of mass and environment. The final survey, which will be completed within 5 years, will consist of a complete magnitude-limited sample (i<17) of about 1.2x10^6 galaxies, supplemented by an extension to higher redshifts and fainter magnitudes (i<18.1) of a luminous red galaxy sample of about 0.8x10^6 galaxies. Observations and data processing will be carried out remotely and in a fully-automated way, using a purpose-built automated 'virtual observer' software and an automated data reduction pipeline. The Taipan survey is deliberately designed to maximise its legacy value, by complementing and enhancing current and planned surveys of the southern sky at wavelengths from the optical to the radio., Comment: Published in PASA; 29 pages, 17 figures, 2 tables

We examine the HI-to-stellar mass ratio (HI fraction) for galaxies near filament backbones within the nearby Universe ($d <$ 181 Mpc). This work uses the 6 degree Field Galaxy Survey and the Discrete Persistent Structures Extractor to define the filamentary structure of the local cosmic web. HI spectral stacking of HI Parkes all sky survey observations yields the HI fraction for filament galaxies and a field control sample. The HI fraction is measured for different stellar masses and fifth nearest neighbour projected densities ($\Sigma_{5}$) to disentangle what influences cold gas in galaxies. For galaxies with stellar masses log($M_{\star}$) $<$ 11 M$_{\odot}$ in projected densities 0 $\leq$ $\Sigma_{5}$ $<$ 3 galaxies Mpc$^{-2}$, all HI fractions of galaxies near filaments are statistically indistinguishable from the control sample. Galaxies with stellar masses log($M_{\star}$) $\geq$ 11 M$_{\odot}$ have a systematically higher HI fraction near filaments than the control sample. The greatest difference is 0.75 dex, which is 5.5$\sigma$ difference at mean projected densities of 1.45 galaxies Mpc$^{-2}$. We suggest that this is evidence for massive galaxies accreting cold gas from the intrafilament medium that can replenish some HI gas. This supports cold mode accretion where filament galaxies with a large gravitational potential can draw gas from the large-scale structure., Comment: 20 pages, 13 figures. Accepted in MNRAS

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 have investigated the effect of group environment on residual star formation in galaxies, using Galex NUV galaxy photometry with the SDSS group catalogue of Yang et al. (2007). We compared the (NUV $- r$) colours of grouped and non-grouped galaxies, and find a significant increase in the fraction of red sequence galaxies with blue (NUV $- r$) colours outside of groups. When comparing galaxies in mass matched samples of satellite (non-central), and non-grouped galaxies, we found a > 4{\sigma} difference in the distribution of (NUV $- r$) colours, and an (NUV $- r$) blue fraction $> 3{\sigma}$ higher outside groups. A comparison of satellite and non-grouped samples has found the NUV fraction is a factor of $\sim2$ lower for satellite galaxies between $10^{10.5}M_{\bigodot}$ and $10^{10.7}M_{\bigodot}$, showing that higher mass galaxies are more able to form stars when not influenced by a group potential. There was a higher (NUV $- r$) blue fraction of galaxies with lower Sersic indices (n < 3) outside of groups, not seen in the satellite sample. We have used stellar population models of Bruzual & Charlot (2003) with multiple burst, or exponentially declining star formation histories to find that many of the (NUV $- r$) blue non-grouped galaxies can be explained by a slow ($\sim 2$ Gyr) decay of star formation, compared to the satellite galaxies. We suggest that taken together, the difference in (NUV $- r$) colours between samples can be explained by a population of secularly evolving, non-grouped galaxies, where star formation declines slowly. This slow channel is less prevalent in group environments where more rapid quenching can occur., Comment: 12 pages, 10 figures, accepted for publication in MNRAS

We measure the bulk flow of the local Universe using the 6dF Galaxy Survey peculiar velocity sample (6dFGSv), the largest and most homogeneous peculiar velocity sample to date. 6dFGSv is a Fundamental Plane sample of $\sim10^4$ peculiar velocities covering the whole southern hemisphere for galactic latitude $|b| > 10^\circ$, out to redshift ${z=0.0537}$. We apply the `Minimum Variance' bulk flow weighting method, which allows us to make a robust measurement of the bulk flow on scales of $50$ and $70\,h^{-1}{\rm Mpc}$. We investigate and correct for potential bias due to the lognormal velocity uncertainties, and verify our method by constructing $\Lambda{\rm CDM}$ 6dFGSv mock catalogues incorporating the survey selection function. For a hemisphere of radius $50\,h^{-1}{\rm Mpc}$ we find a bulk flow amplitude of $U=248\pm58\,{\rm km}\,{\rm s}^{-1}$ in the direction $(l,b) = (318^\circ\pm20^\circ,40^\circ\pm13^\circ)$, and for $70\,h^{-1}{\rm Mpc}$ we find $U=243\pm58\,{\rm km}\,{\rm s}^{-1}$, in the same direction. Our measurement gives us a constraint on $\sigma_8$ of $1.01^{+1.07}_{-0.58}$. Our results are in agreement with other recent measurements of the direction of the bulk flow, and our measured amplitude is consistent with a $\Lambda{\rm CDM}$ prediction., Comment: 17 pages, 13 figures. Accepted for publication in MNRAS

Using the Tully-Fisher relation, we derive peculiar velocities for the 2MASS Tully-Fisher Survey and describe the velocity field of the nearby Universe. We use adaptive kernel smoothing to map the velocity field, and compare it to reconstructions based on the redshift space galaxy distributions of the 2MASS Redshift Survey (2MRS) and the IRAS Point Source Catalog Redshift Survey (PSCz). With a standard $\chi^2$ minimization fit to the models, we find that the PSCz model provides a better fit to the 2MTF velocity field data than does the 2MRS model, and provides a value of $\beta$ in greater agreement with literature values. However, when we subtract away the monopole deviation in the velocity zeropoint between data and model, the 2MRS model also produces a value of $\beta$ in agreement with literature values. We also calculate the `residual bulk flow': the component of the bulk flow not accounted for by the models. This is $\sim 250$ km/s when performing the standard fit, but drops to $\sim 150$ km/s for both models when the aforementioned monopole offset between data and models is removed. This smaller number is more in line with theoretical expectations, and suggests that the models largely account for the major structures in the nearby Universe responsible for the bulk velocity., Comment: 16 pages, 9 figures, 2 tables, accepted for publication in MNRAS

We examine the properties of galaxies in the Galaxies and Mass Assembly (GAMA) survey located in voids with radii $>10~h^{-1}$ Mpc. Utilising the GAMA equatorial survey, 592 void galaxies are identified out to z~0.1 brighter than $M_{r} = -18.4$, our magnitude completeness limit. Using the $W_{\rm{H\alpha}}$ vs. [NII]/H$\alpha$ (WHAN) line strength diagnostic diagram, we classify their spectra as star forming, AGN, or dominated by old stellar populations. For objects more massive than $5\times10^{9}$ M$_{\odot}$, we identify a sample of 26 void galaxies with old stellar populations classed as passive and retired galaxies in the WHAN diagnostic diagram, else they lack any emission lines in their spectra. When matched to WISE mid-IR photometry, these passive and retired galaxies exhibit a range of mid-IR colour, with a number of void galaxies exhibiting [4.6]-[12] colours inconsistent with completely quenched stellar populations, with a similar spread in colour seen for a randomly drawn non-void comparison sample. We hypothesise that a number of these galaxies host obscured star formation, else they are star forming outside of their central regions targeted for single fibre spectroscopy. When matched to a randomly drawn sample of non-void galaxies, the void and non-void galaxies exhibit similar properties in terms of optical and mid-IR colour, morphology, and star formation activity, suggesting comparable mass assembly and quenching histories. A trend in mid-IR [4.6]-[12] colour is seen, such that both void and non-void galaxies with quenched/passive colours <1.5 typically have masses higher than $10^{10}$ M$_{\odot}$, where internally driven processes play an increasingly important role in galaxy evolution., Comment: 22 pages, 12 figures. Accepted for publication in MNRAS

We present the GAMA Panchromatic Data Release (PDR) constituting over 230deg$^2$ of imaging with photometry in 21 bands extending from the far-UV to the far-IR. These data complement our spectroscopic campaign of over 300k galaxies, and are compiled from observations with a variety of facilities including: GALEX, SDSS, VISTA, WISE, and Herschel, with the GAMA regions currently being surveyed by VST and scheduled for observations by ASKAP. These data are processed to a common astrometric solution, from which photometry is derived for 221,373 galaxies with r<19.8 mag. Online tools are provided to access and download data cutouts, or the full mosaics of the GAMA regions in each band. We focus, in particular, on the reduction and analysis of the VISTA VIKING data, and compare to earlier datasets (i.e., 2MASS and UKIDSS) before combining the data and examining its integrity. Having derived the 21-band photometric catalogue we proceed to fit the data using the energy balance code MAGPHYS. These measurements are then used to obtain the first fully empirical measurement of the 0.1-500$\mu$m energy output of the Universe. Exploring the Cosmic Spectral Energy Distribution (CSED) across three time-intervals (0.3-1.1Gyr, 1.1-1.8~Gyr and 1.8---2.4~Gyr), we find that the Universe is currently generating $(1.5 \pm 0.3) \times 10^{35}$ h$_{70}$ W Mpc$^{-3}$, down from $(2.5 \pm 0.2) \times 10^{35}$ h$_{70}$ W Mpc$^{-3}$ 2.3~Gyr ago. More importantly, we identify significant and smooth evolution in the integrated photon escape fraction at all wavelengths, with the UV escape fraction increasing from 27(18)% at z=0.18 in NUV(FUV) to 34(23)% at z=0.06. The GAMA PDR will allow for detailed studies of the energy production and outputs of individual systems, sub-populations, and representative galaxy samples at $z<0.5$. The GAMA PDR can be found at: http://gama-psi.icrar.org/, Comment: 31 pages and 30 figures. Accepted in MNRAS. High-resolution copy available from our release site: http://gama-psi.icrar.org/ or directly via http://www.simondriver.org/mwavev05.pdf

Using new integral field observations of 106 galaxies in three nearby clusters we investigate how the intrinsic scatter of the Fundamental Plane depends on the way in which the velocity dispersion and effective radius are measured. Our spatially resolved spectroscopy, combined with a cluster sample with negligible relative distance errors allows us to derive a Fundamental Plane with minimal systematic uncertainties. From the apertures we tested, we find that velocity dispersions measured within a circular aperture with radius equal to one effective radius minimises the intrinsic scatter of the Fundamental Plane. Using simple yet powerful Jeans dynamical models we determine dynamical masses for our galaxies. Replacing luminosity in the Fundamental Plane with dynamical mass, we demonstrate that the resulting Mass Plane has further reduced scatter, consistent with zero intrinsic scatter. Using these dynamical models we also find evidence for a possibly non-linear relationship between dynamical mass-to-light ratio and velocity dispersion., Comment: 15 pages, 11 figures. Accepted for publication in MNRAS

We present a proof-of-concept of a novel and fully Bayesian methodology designed to detect halos of different masses in cosmological observations subject to noise and systematic uncertainties. Our methodology combines the previously published Bayesian large-scale structure inference algorithm, HADES, and a Bayesian chain rule (the Blackwell-Rao Estimator), which we use to connect the inferred density field to the properties of dark matter halos. To demonstrate the capability of our approach we construct a realistic galaxy mock catalogue emulating the wide-area 6-degree Field Galaxy Survey, which has a median redshift of approximately 0.05. Application of HADES to the catalogue provides us with accurately inferred three-dimensional density fields and corresponding quantification of uncertainties inherent to any cosmological observation. We then use a cosmological simulation to relate the amplitude of the density field to the probability of detecting a halo with mass above a specified threshold. With this information we can sum over the HADES density field realisations to construct maps of detection probabilities and demonstrate the validity of this approach within our mock scenario. We find that the probability of successful of detection of halos in the mock catalogue increases as a function of the signal-to-noise of the local galaxy observations. Our proposed methodology can easily be extended to account for more complex scientific questions and is a promising novel tool to analyse the cosmic large-scale structure in observations., Comment: 17 pages, 13 figures. Accepted for publication in MNRAS following moderate corrections

We derive peculiar velocities for the 6dF Galaxy Survey (6dFGS) and describe the velocity field of the nearby ($z<0.055$) southern hemisphere. The survey comprises 8885 galaxies for which we have previously reported Fundamental Plane data. We obtain peculiar velocity probability distributions for the redshift space positions of each of these galaxies using a Bayesian approach. Accounting for selection bias, we find that the logarithmic distance uncertainty is 0.11 dex, corresponding to $26\%$ in linear distance. We use adaptive kernel smoothing to map the observed 6dFGS velocity field out to $cz \sim 16,000$ \kms, and compare this to the predicted velocity fields from the PSCz Survey and the 2MASS Redshift Survey. We find a better fit to the PSCz prediction, although the reduced $\chi^2$ for the whole sample is approximately unity for both comparisons. This means that, within the observational uncertainties due to redshift independent distance errors, observed galaxy velocities and those predicted by the linear approximation from the density field agree. However, we find peculiar velocities that are systematically more positive than model predictions in the direction of the Shapley and Vela superclusters, and systematically more negative than model predictions in the direction of the Pisces-Cetus Supercluster, suggesting contributions from volumes not covered by the models., Comment: 22 pages, 14 figures, accepted for publication in MNRAS. Table 1 is available in its entirety as an ancillary file. Fully interactive 3D versions of Figures 11 and 12 are also available as ancillary files. A version of this paper with the 3D versions of Figs. 11 and 12 embedded within the pdf can also be accessed from http://www.6dfgs.net/vfield/veldata.pdf

Using the 2MASS near-infrared photometry and high signal-to-noise HI 21-cm data from the Arecibo, Green Bank, Nancay, and Parkes telescopes, we calculate the redshift-independent distances and peculiar velocities of 2,018 bright inclined spiral galaxies over the whole sky. This project is part of the 2MASS Tully-Fisher survey (2MTF), aiming to map the galaxy peculiar velocity field within 100 h^{-1}Mpc, with an all-sky coverage apart from Galactic latitudes |b|< 5 deg. A \chi^2 minimization method was adopted to analyze the Tully-Fisher peculiar velocity field in J, H and K bands, using a Gaussian filter. We combine information from the three wavebands, to provide bulk flow measurements of 310.9 +/- 33.9 km/s, 280.8 +/- 25.0 km/s, and 292.3 +/- 27.8 km/s at depths of 20 h^{-1}Mpc, 30 h^{-1}Mpc and 40 h^{-1}Mpc, respectively. Each of these bulk flow vectors points in a direction similar to those found by previous measurements. At each of the three depths, the bulk flow magnitude is consistent with predictions made by the $\Lambda$CDM model at the 1$\sigma$ level. The maximum likelihood and minimum variance method were also used to analyze the 2MTF samples, giving similar results., Comment: 12 pages, 15 figures, 3 tables, accepted for publication in MNRAS

We report the 6dFGS Fundamental Plane (6dFGSv) catalogue that is used to estimate distances and peculiar velocities for nearly 9,000 early-type galaxies in the local (z$<$0.055) universe. Velocity dispersions are derived by cross-correlation from 6dF V-band spectra with typical S/N of 12.9 \AA$^{-1}$ for a sample of 11,315 galaxies; the median velocity dispersion is 163 kms$^{-1}$ and the median measurement error is 12.9%. The photometric Fundamental Plane (FP) parameters (effective radii and surface brightnesses) are determined from the $JHK$ 2MASS images for 11,102 galaxies. Comparison of the independent $J$- and $K$-band measurements implies that the average uncertainty in $X_{FP}$, the combined photometric parameter that enters the FP, is 0.013 dex (3%) for each band. Visual classification of morphologies was used to select a sample of nearly 9,000 early-type galaxies that form 6dFGSv. This catalogue has been used to study the effects of stellar populations on galaxy scaling relations, to investigate the variation of the FP with environment and galaxy morphology, to explore trends in stellar populations through, along and across the FP, and to map and analyse the local peculiar velocity field., Comment: 21 pages, 25 figures, 9 tables, accepted for publication in MNRAS, the full versions of Tables 2, 4, 8 and 9 will be available in the MNRAS publication as online Supporting Information

We examine the kinematic morphology of early-type galaxies (ETGs) in three galaxy clusters Abell 85, 168 and 2399. Using data from the Sydney-AAO Multi-object Integral field spectrograph (SAMI) we measured spatially-resolved kinematics for 79 ETGs in these clusters. We calculate $\lambda_{R}$, a proxy for the projected specific stellar angular momentum, for each galaxy and classify the 79 ETGs in our samples as fast or slow rotators. We calculate the fraction of slow rotators in the ETG populations ($f_{SR}$) of the clusters to be $0.21\pm0.08$, $0.08\pm0.08$ and $0.12\pm0.06$ for Abell 85, 168 and 2399 respectively, with an overall fraction of $0.15\pm0.04$. These numbers are broadly consistent with the values found in the literature, confirming recent work asserting that the fraction of slow rotators in the ETG population is constant across many orders of magnitude in global environment. We examine the distribution of kinematic classes in each cluster as a function of environment using the projected density of galaxies: the kinematic morphology-density relation. We find that in Abell 85 $f_{SR}$ increases in higher density regions but in Abell 168 and Abell 2399 this trend is not seen. We examine the differences between the individual clusters to explain this. In addition, we find slow rotators on the outskirts of two of the clusters studied, Abell 85 and 2399. These galaxies reside in intermediate to low density regions and have clearly not formed at the centre of a cluster environment. We hypothesise that they formed at the centres of groups and are falling into the clusters for the first time., Comment: 21 pages, 13 figures, accepted for publication in MNRAS

We present a photometric investigation into recent star formation in galaxy clusters at z ~ 0.1. We use spectral energy distribution templates to quantify recent star formation in large X-ray selected clusters from the LARCS survey using matched GALEX NUV photometry. These clusters all have signs of red sequence galaxy recent star formation (as indicated by blue NUV-R colour), regardless of cluster morphology and size. A trend in environment is found for these galaxies, such that they prefer to occupy low density, high cluster radius environments. The morphology of these UV bright galaxies suggests that they are in fact red spirals, which we confirm with light curves and Galaxy Zoo voting percentages as morphological proxies. These UV bright galaxies are therefore seen to be either truncated spiral galaxies, caught by ram pressure in falling into the cluster, or high mass spirals, with the photometry dominated by the older stellar population., Comment: Accepted for publication in MNRAS, 11 pages, 11 figures

We present a mid-infrared Tully-Fisher (TF) relation using photometry from the 3.4-micron W1 band of the Wide-field Infrared Survey Explorer (WISE) satellite. The WISE TF relation is formed from 568 galaxies taken from the all-sky 2MASS Tully-Fisher (2MTF) galaxy catalog, spanning a range of environments including field, group, and cluster galaxies. This constitutes the largest mid-infrared TF relation constructed, to date. After applying a number of corrections to galaxy magnitudes and line widths, we measure a master TF relation given by M_corr = -22.24 - 10.05[log(W_corr) - 2.5], with an average dispersion of sigma_WISE = 0.686 magnitudes. There is some tension between WISE TF and a preliminary 3.6-micron relation, which has a shallower slope and almost no intrinsic dispersion. However, our results agree well with a more recent relation constructed from a large sample of cluster galaxies. We additionally compare WISE TF to the near-infrared 2MTF template relations, finding a good agreement between the TF parameters and total dispersions of WISE TF and the 2MTF K-band template. This fact, coupled with typical galaxy colors of (K - W1) ~ 0, suggests that these two bands are tracing similar stellar populations, including the older, centrally-located stars in the galactic bulge which can (for galaxies with a prominent bulge) dominate the light profile., Comment: 13 pages, 13 figures, 1 table. Accepted to ApJ. (A machine-readable version of Table 1 is included with this submission.)

We examine the hypothesis that mergers and close encounters between galaxies can fuel AGNs by increasing the rate at which gas accretes towards the central black hole. We compare the clustering of galaxies around radio-loud AGNs with the clustering around a population of radio-quiet galaxies with similar masses, colors and luminosities. Our catalog contains 2178 elliptical radio galaxies with flux densities greater than 2.8 mJy at 1.4 GHz from the 6dFGS survey. We find that radio AGNs with more than 200 times the median radio power have, on average, more close (r<160 kpc) companions than their radio-quiet counterparts, suggestive that mergers play a role in forming the most powerful radio galaxies. For ellipticals of fixed stellar mass, the radio power is not a function of large-scale environment nor halo mass, consistent with the radio powers of ellipticals varying by orders of magnitude over billions of years., Comment: 12 pages, 6 figures

We present new 21-cm neutral hydrogen (HI) observations of spiral galaxies for the 2MASS Tully Fisher (2MTF) survey. Using the 64-m Parkes radio telescope multibeam system we obtain 152 high signal-to-noise HI spectra from which we extract 148 high-accuracy (< 5% error) velocity widths and derive reliable rotation velocities. The observed sample consists of 303 southern (\delta < -40\deg) galaxies selected from the MASS Redshift Survey (2MRS) with K_s <11.25 mag, cz < 10,000 km/s and axis ratio b/a < 0.5. The HI observations reported in this paper will be combined with new HI spectra from the Green Bank and Arecibo telescopes, together producing the most uniform Tully-Fisher survey ever constructed (in terms of sky coverage). In particular, due to its near infrared selection, 2MTF will be significantly more complete at low Galactic latitude (|b|<15\deg) and will provide a more reliable map of peculiar velocities in the local universe., Comment: 11 pages, 12 figures, 3 tables, accepted for publication in MNRAS

In this paper we study the stellar-mass dependence of galaxy clustering in the 6dF Galaxy Survey. The near-infrared selection of 6dFGS allows more reliable stellar mass estimates compared to optical bands used in other galaxy surveys. Using the Halo Occupation Distribution (HOD) model, we investigate the trend of dark matter halo mass and satellite fraction with stellar mass by measuring the projected correlation function, $w_p(r_p)$. We find that the typical halo mass ($M_1$) as well as the satellite power law index ($\alpha$) increase with stellar mass. This indicates, (1) that galaxies with higher stellar mass sit in more massive dark matter halos and (2) that these more massive dark matter halos accumulate satellites faster with growing mass compared to halos occupied by low stellar mass galaxies. Furthermore we find a relation between $M_1$ and the minimum dark matter halo mass ($M_{\rm min}$) of $M_1 \approx 22\,M_{\rm min}$, in agreement with similar findings for SDSS galaxies. The satellite fraction of 6dFGS galaxies declines with increasing stellar mass from 21% at $M_{\rm stellar} = 2.6\times10^{10}h^{-2}\,M_{\odot}$ to 12% at $M_{\rm stellar} = 5.4\times10^{10}h^{-2}\,M_{\odot}$ indicating that high stellar mass galaxies are more likely to be central galaxies. We compare our results to two different semi-analytic models derived from the Millennium Simulation, finding some disagreement. Our results can be used for placing new constraints on semi-analytic models in the future, particularly the behaviour of luminous red satellites. Finally we compare our results to studies of halo occupation using galaxy-galaxy weak lensing. We find good overall agreement, representing a valuable crosscheck for these two different tools of studying the matter distribution in the Universe., Comment: 17 pages, 11 figures. arXiv admin note: text overlap with arXiv:1104.2447 by other authors

We present the first scientific results from the Sydney-AAO Multi-Object IFS (SAMI) at the Anglo-Australian Telescope. This unique instrument deploys 13 fused fibre bundles (hexabundles) across a one-degree field of view allowing simultaneous spatially-resolved spectroscopy of 13 galaxies. During the first SAMI commissioning run, targeting a single galaxy field, one object (ESO 185-G031) was found to have extended minor axis emission with ionisation and kinematic properties consistent with a large-scale galactic wind. The importance of this result is two-fold: (i) fibre bundle spectrographs are able to identify low-surface brightness emission arising from extranuclear activity; (ii) such activity may be more common than presently assumed because conventional multi-object spectrographs use single-aperture fibres and spectra from these are nearly always dominated by nuclear emission. These early results demonstrate the extraordinary potential of multi-object hexabundle spectroscopy in future galaxy surveys., Comment: 12 pages, 14 figures, accepted for publication in ApJ 01/Nov/2012

We determine the near-infrared Fundamental Plane (FP) for $\sim10^4$ early-type galaxies in the 6dF Galaxy Survey (6dFGS). We fit the distribution of central velocity dispersion, near-infrared surface brightness and half-light radius with a three-dimensional Gaussian model using a maximum likelihood method. For the 6dFGS $J$ band sample we find a FP with $R_{e}$\,$\propto$\,$\sigma_0^{1.52\pm0.03}I_{e}^{-0.89\pm0.01}$, similar to previous near-IR determinations and consistent with the $H$ and $K$ band Fundamental Planes once allowance is made for differences in mean colour. The overall scatter in $R_e$ about the FP is $\sigma_r$,=,29%, and is the quadrature sum of an 18% scatter due to observational errors and a 23% intrinsic scatter. Because of the distribution of galaxies in FP space, $\sigma_r$ is not the distance error, which we find to be $\sigma_d$,=,23%. Using group richness and local density as measures of environment, and morphologies based on visual classifications, we find that the FP slopes do not vary with environment or morphology. However, for fixed velocity dispersion and surface brightness, field galaxies are on average 5% larger than galaxies in higher-density environments, and the bulges of early-type spirals are on average 10% larger than ellipticals and lenticulars. The residuals about the FP show significant trends with environment, morphology and stellar population. The strongest trend is with age, and we speculate that age is the most important systematic source of offsets from the FP, and may drive the other trends through its correlations with environment, morphology and metallicity., Comment: 29 pages, 20 figures, accepted for publication in MNRAS. A version of this paper with fully interactive 3D figures, viewable with Adobe Reader 8.0 or higher, can be accessed from: http://www.aao.gov.au/6dFGS/Publications/REFEREED/fpfit_paper3d.pdf

We present a detailed analysis of redshift-space distortions in the two-point correlation function of the 6dF Galaxy Survey (6dFGS). The K-band selected sub-sample which we employ in this study contains 81971 galaxies distributed over 17000deg^2 with an effective redshift z = 0.067. By modelling the 2D galaxy correlation function, xi(r_p,pi), we measure the parameter combination f(z)sigma_8(z) = 0.423 +/- 0.055. Alternatively, by assuming standard gravity we can break the degeneracy between sigma_8 and the galaxy bias parameter, b. Combining our data with the Hubble constant prior from Riess et al (2011), we measure sigma_8 = 0.76 +/- 0.11 and Omega_m = 0.250 +/- 0.022, consistent with constraints from other galaxy surveys and the Cosmic Microwave Background data from WMAP7. Combining our measurement of fsigma_8 with WMAP7 allows us to test the relationship between matter and gravity on cosmic scales by constraining the growth index of density fluctuations, gamma. Using only 6dFGS and WMAP7 data we find gamma = 0.547 +/- 0.088, consistent with the prediction of General Relativity. We note that because of the low effective redshift of 6dFGS our measurement of the growth rate is independent of the fiducial cosmological model (Alcock-Paczynski effect). We also show that our conclusions are not sensitive to the model adopted for non-linear redshift-space distortions. Using a Fisher matrix analysis we report predictions for constraints on fsigma_8 for the WALLABY survey and the proposed TAIPAN survey. The WALLABY survey will be able to measure fsigma_8 with a precision of 4-10%, depending on the modelling of non-linear structure formation. This is comparable to the predicted precision for the best redshift bins of the Baryon Oscillation Spectroscopic Survey (BOSS), demonstrating that low-redshift surveys have a significant role to play in future tests of dark energy and modified gravity., Comment: 17 pages, 13 figures, 1 table

We demonstrate a novel technology that combines the power of the multi-object spectrograph with the spatial multiplex advantage of an integral field spectrograph (IFS). The Sydney-AAO Multi-object IFS (SAMI) is a prototype wide-field system at the Anglo-Australian Telescope (AAT) that allows 13 imaging fibre bundles ("hexabundles") to be deployed over a 1-degree diameter field of view. Each hexabundle comprises 61 lightly-fused multimode fibres with reduced cladding and yields a 75 percent filling factor. Each fibre core diameter subtends 1.6 arcseconds on the sky and each hexabundle has a field of view of 15 arcseconds diameter. The fibres are fed to the flexible AAOmega double-beam spectrograph, which can be used at a range of spectral resolutions (R=lambda/delta(lambda) ~ 1700-13000) over the optical spectrum (3700-9500A). We present the first spectroscopic results obtained with SAMI for a sample of galaxies at z~0.05. We discuss the prospects of implementing hexabundles at a much higher multiplex over wider fields of view in order to carry out spatially--resolved spectroscopic surveys of 10^4 to 10^5 galaxies., Comment: 24 pages, 16 figures. Accepted by MNRAS

We present results from an analysis of stellar population parameters for 7132 galaxies in the 6dFGS Fundamental Plane (FP) sample. We bin the galaxies along the axes, $v_1$, $v_2$, and $v_3$, of the tri-variate Gaussian to which we have fit the galaxy distribution in effective radius, surface brightness, and central velocity dispersion (FP space), and compute median values of stellar age, [Fe/H], [Z/H], and [$\alpha$/Fe]. We determine the directions of the vectors in FP space along which each of the binned stellar population parameters vary most strongly. In contrast to previous work, we find stellar population trends not just with velocity dispersion and FP residual, but with radius and surface brightness as well. The most remarkable finding is that the stellar population parameters vary through the plane ($v_1$ direction) and across the plane ($v_3$ direction), but show no variation at all along the plane ($v_2$ direction). The $v_2$ direction in FP space roughly corresponds to `luminosity density'. We interpret a galaxy's position along this vector as being closely tied to its merger history, such that early-type galaxies with lower luminosity density are more likely to have undergone major mergers. This conclusion is reinforced by an examination of the simulations of Kobayashi (2005), which show clear trends of merger history with $v_2$., Comment: 13 pages, 14 figures, accepted for publication in MNRAS. A version of this paper with fully interactive 3D figures, viewable with Adobe Reader 8.0 or higher, is available as an ancillary file with this release, and can also be accessed from this link

We analyse the large-scale correlation function of the 6dF Galaxy Survey (6dFGS) and detect a Baryon Acoustic Oscillation (BAO) signal. The 6dFGS BAO detection allows us to constrain the distance-redshift relation at z_{\rm eff} = 0.106. We achieve a distance measure of D_V(z_{\rm eff}) = 456\pm27 Mpc and a measurement of the distance ratio, r_s(z_d)/D_V(z_{\rm eff}) = 0.336\pm0.015 (4.5% precision), where r_s(z_d) is the sound horizon at the drag epoch z_d. The low effective redshift of 6dFGS makes it a competitive and independent alternative to Cepheids and low-z supernovae in constraining the Hubble constant. We find a Hubble constant of H_0 = 67\pm3.2 km s^{-1} Mpc^{-1} (4.8% precision) that depends only on the WMAP-7 calibration of the sound horizon and on the galaxy clustering in 6dFGS. Compared to earlier BAO studies at higher redshift, our analysis is less dependent on other cosmological parameters. The sensitivity to H_0 can be used to break the degeneracy between the dark energy equation of state parameter w and H_0 in the CMB data. We determine that w = -0.97\pm0.13, using only WMAP-7 and BAO data from both 6dFGS and \citet{Percival:2009xn}. We also discuss predictions for the large scale correlation function of two future wide-angle surveys: the WALLABY blind H{\sc I} survey (with the Australian SKA Pathfinder, ASKAP), and the proposed TAIPAN all-southern-sky optical galaxy survey with the UK Schmidt Telescope (UKST). We find that both surveys are very likely to yield detections of the BAO peak, making WALLABY the first radio galaxy survey to do so. We also predict that TAIPAN has the potential to constrain the Hubble constant with 3% precision., Comment: 18 pages, 17 figures, 3 tables

We present the burst ages for young stellar populations in a sample of six nearby (< 10 Mpc) spiral galaxies using a differential pixel-based analysis of the ionized gas emission. We explore this as an alternative approach for connecting large-scale dynamical mechanisms with star formation processes in disk galaxies, based on burst ages derived from the Ha to far UV (FUV) flux ratio. Images of each galaxy in Ha were taken with Taurus Tunable Filter (TTF) and matched to FUV imaging from GALEX. The resulting flux ratio provides a robust measure of relative age across the disk which we discuss in terms of the large-scale dynamical motions. Systematic effects, such as a variable initial mass function (IMF), non-solar metallicities, variable star-formation history (SFHs), and dust attenuation, have been used to derive estimates of the systematic uncertainty. The resulting age maps show a wide range of patterns outside of those galaxies with the strongest spiral structure, confirming the idea that star formation is driven one by several processes, largely determined by the individual circumstances of the galaxy. Generally, grand design spirals such as M74, M100, and M51 exhibit age gradients across the main spiral arms, with the youngest star formation regions along the central and inner edges. In M63 and M74 galaxy-wide trends emerge, suggesting that although most star formation is located along spiral arms, spiral density waves are not the only driver in these cases. We argue that despite appearances, galaxy morphology is not an absolute discriminator of the star formation history of an individual galaxy, nor of the processes triggering it. We conclude that Ha-to-FUV flux ratios are a relatively direct way to probe burst ages across galaxies and infer something of their dynamical histories, provided that sources of systematics are properly taken into account., Comment: The paper contains 22 pages, 13 figures and 5 tables

In order to generate credible 0.1-2 {\mu}m SEDs, the GAMA project requires many Gigabytes of imaging data from a number of instruments to be re-processed into a standard format. In this paper we discuss the software infrastructure we use, and create self-consistent ugrizYJHK photometry for all sources within the GAMA sample. Using UKIDSS and SDSS archive data, we outline the pre-processing necessary to standardise all images to a common zeropoint, the steps taken to correct for seeing bias across the dataset, and the creation of Gigapixel-scale mosaics of the three 4x12 deg GAMA regions in each filter. From these mosaics, we extract source catalogues for the GAMA regions using elliptical Kron and Petrosian matched apertures. We also calculate S\'ersic magnitudes for all galaxies within the GAMA sample using SIGMA, a galaxy component modelling wrapper for GALFIT 3. We compare the resultant photometry directly, and also calculate the r band galaxy LF for all photometric datasets to highlight the uncertainty introduced by the photometric method. We find that (1) Changing the object detection threshold has a minor effect on the best-fitting Schechter parameters of the overall population (M* +/- 0.055mag, {\alpha} +/- 0.014, {\Phi}* +/- 0.0005 h^3 Mpc^{-3}). (2) An offset between datasets that use Kron or Petrosian photometry regardless of the filter. (3) The decision to use circular or elliptical apertures causes an offset in M* of 0.20mag. (4) The best-fitting Schechter parameters from total-magnitude photometric systems (such as SDSS modelmag or S\'ersic magnitudes) have a steeper faint-end slope than photometry dependent on Kron or Petrosian magnitudes. (5) Our Universe's total luminosity density, when calculated using Kron or Petrosian r-band photometry, is underestimated by at least 15%., Comment: 38 pages, 10 Tables, 26 figures. Submitted to MNRAS (revised once). Image resolution has been lowered. For higher resolution, see http://www.gama-survey.org/

The Two Micron All-Sky Survey (2MASS) has provided a uniform photometric catalog to search for previously unknown red AGN and QSOs. We have extended the search to the southern equatorial sky by obtaining spectra for 1182 AGN candidates using the 6dF multifibre spectrograph on the UK Schmidt Telescope. These were scheduled as auxiliary targets for the 6dF Galaxy Redshift Survey. The candidates were selected using a single color cut of J - Ks > 2 to Ks ~ 15.5 and a galactic latitude of |b|>30 deg. 432 spectra were of sufficient quality to enable a reliable classification. 116 sources (or ~27%) were securely classified as type 1 AGN, 20 as probable type 1s, and 57 as probable type 2 AGN. Most of them span the redshift range 0.0520%) than in any previous galaxy survey. A small fraction of the type 1 AGN could have their optical colors reddened by optically thin dust with A_V<2 mag relative to optically selected QSOs. A handful show evidence for excess far-IR emission. The equivalent width (EW) and color distributions of the type 1 and 2 AGN are consistent with AGN unified models. In particular, the EW of the [OIII] emission line weakly correlates with optical--near-IR color in each class of AGN, suggesting anisotropic obscuration of the AGN continuum. Overall, the optical properties of the 2MASS red AGN are not dramatically different from those of optically-selected QSOs. Our near-IR selection appears to detect the most near-IR luminous QSOs in the local universe to z~0.6 and provides incentive to extend the search to deeper near-IR surveys., Comment: 57 pages, 12 figures, 4 tables, to appear in vol.27/4 of Publications of the Astronomical Society of Australia (PASA)

We have used over 10,000 early-type galaxies from the 6dF Galaxy Survey (6dFGS) to construct the Fundamental Plane across the optical and near-infrared passbands. We demonstrate that a maximum likelihood fit to a multivariate Gaussian model for the distribution of galaxies in size, surface brightness and velocity dispersion can properly account for selection effects, censoring and observational errors, leading to precise and unbiased parameters for the Fundamental Plane and its intrinsic scatter. This method allows an accurate and robust determination of the dependencies of the Fundamental Plane on variations in the stellar populations and environment of early-type galaxies., Comment: 3 pages, 1 figure, to appear in the proceedings of the IAU Symposium 262 "Stellar Populations: Planning for the Next Decade", Charlot and Bruzual eds

We report the final redshift release of the 6dF Galaxy Survey, a combined redshift and peculiar velocity survey over the southern sky (|b|>10 deg). Its 136,304 spectra have yielded 110,256 new extragalactic redshifts and a new catalogue of 125,071 galaxies making near-complete samples with (K, H, J, r_F, b_J) <= (12.65, 12.95, 13.75, 15.60, 16.75). The median redshift of the survey is 0.053. Survey data, including images, spectra, photometry and redshifts, are available through an online database. We describe changes to the information in the database since earlier interim data releases. Future releases will include velocity dispersions, distances and peculiar velocities for the brightest early-type galaxies, comprising about 10% of the sample. Here we provide redshift maps of the southern local universe with z<=0.1, showing nearby large-scale structures in hitherto unseen detail. A number of regions known previously to have a paucity of galaxies are confirmed as significantly underdense regions. The URL of the 6dFGS database is http://www-wfau.roe.ac.uk/6dFGS, Comment: 18 pages, 9 figures, submitted to MNRAS. Higher resolution version available from http://www.aao.gov.au/6dFGS/Publications

We use narrowband imaging (FWHM = 70 A) to select a sample of emission line galaxies between 0.20 <~ z <~ 1.22 in two fields covering 0.5 sq. deg. We use spectroscopic follow-up to select a sub-sample of Halpha emitting galaxies at z ~ 0.24 and determine the Halpha luminosity function and star formation density at z ~ 0.24 for both of our fields. Corrections are made for imaging and spectroscopic incompleteness, extinction and interloper contamination on the basis of the spectroscopic data. When compared to each other, we find the field samples differ by \Delta \alpha = 0.2 in faint end slope and \Delta \log [ L* (ergs/s) ] = 0.2 in luminosity. In the context of other recent surveys, our sample has comparable faint end slope, but a fainter L* turn-over. We conclude that systematic uncertainties and differences in selection criteria remain the dominant sources of uncertainty between Halpha luminosity functions at this redshift. We also investigate average star formation rates as a function of local environment and find typical values consistent with the field densities that we probe, in agreement with previous results. However, we find tentative evidence for an increase in star formation rate with respect to the local density of star forming galaxies, consistent with the scenario that galaxy-galaxy interactions are triggers for bursts of star formation., Comment: Accepted for publication in MNRAS. The paper contains 14 figures and 7 tables

We present the reconstructed real-space density and the predicted velocity fields from the Two Mass Redshift Survey (2MRS). The 2MRS is the densest all-sky redshift survey to date and includes about 23,200 galaxies with extinction corrected magnitudes brighter than K = 11.25. Our method is based on the expansion of these fields in Fourier-Bessel functions. Within this framework, the linear redshift distortions only affect the density field in the radial direction and can easily be deconvolved using a distortion matrix. Moreover, in this coordinate system, the velocity field is related to the density field by a simple linear transformation. The shot noise errors in the reconstructions are suppressed by means of a Wiener filter which yields a minimum variance estimate of the density and velocity fields. Using the reconstructed real-space density fields, we identify all major superclusters and voids. At 50 Mpc/h, our reconstructed velocity field indicates a back-side infall to the Great Attractor region of vi = (491 +/- 200)(beta/0.5) km/sec in the Local Group frame and v = (64 +/- 205)(beta/0.5) km/sec in the cosmic microwave background (CMB) frame and beta is the redshift distortion parameter. The direction of the reconstructed dipole agrees well with the dipole derived by Erdogdu et al. (2006). The misalignment between the reconstructed 2MRS and the CMB dipoles drops to 13 degrees at around 5000 km/sec but then increases at larger distances. A version of this paper with high resolution figures can be obtained from http://www.nottingham.ac.uk/~ppzzpe, Comment: 21 pages. 22 figures, accepted for publication in MNRAS. The figures are coarsely resolved, a version of this paper with high resolution figures can be obtained from http://www.nottingham.ac.uk/~ppzzpe

Context: Wide-field narrowband surveys are an efficient way of searching large volumes of high-redshift space for distant galaxies. Aims: We describe the Wide Field Imager Lyman-Alpha Search (WFILAS) over 0.74 sq. degree for bright emission-line galaxies at z~5.7. Methods: WFILAS uses deep images taken with the Wide Field Imager (WFI) on the ESO/MPI 2.2m telescope in three narrowband (70 A), one encompassing intermediate band (220 A) and two broadband filters, B and R. We use the novel technique of an encompassing intermediate band filter to exclude false detections. Images taken with broadband B and R filters are used to remove low redshift galaxies from our sample. Results: We present a sample of seven Lya emitting galaxy candidates, two of which are spectroscopically confirmed. Compared to other surveys all our candidates are bright, the results of this survey complements other narrowband surveys at this redshift. Most of our candidates are in the regime of bright luminosities, beyond the reach of less voluminous surveys. Adding our candidates to those of another survey increases the derived luminosity density by ~30%. We also find potential clustering in the Chandra Deep Field South, supporting overdensities discovered by other surveys. Based on a FORS2/VLT spectrum we additionally present the analysis of the second confirmed Lya emitting galaxy in our sample. We find that it is the brightest Lya emitting galaxy (1 x 10^-16 erg s^-1 cm^-2) at this redshift to date and the second confirmed candidate of our survey. Both objects exhibit the presence of a possible second Lya component redward of the line., Comment: 15 pages, accepted for publication in A&A Replaced with published version

Luminosity functions and their integrated luminosity densities are presented for the 6dF Galaxy Survey (6dFGS). This ongoing survey ultimately aims to measure around 150,000 redshifts and 15,000 peculiar velocities over almost the entire southern sky at |b|>10 deg. The main target samples are taken from the 2MASS Extended Source Catalog and the SuperCOSMOS Sky Survey catalogue, and comprise 138,226 galaxies complete to (K, H, J, rF, bJ) = (12.75, 13.00, 13.75, 15.60, 16.75). These samples are comparable in size to the optically-selected Sloan Digital Sky Survey and 2dF Galaxy Redshift Survey samples, and improve on recent near-infrared-selected redshift surveys by more than an order of magnitude in both number and sky coverage. The partial samples used in this paper contain a little over half of the total sample in each band and are ~90 percent complete. Luminosity distributions are derived using the 1/Vmax, STY and SWML estimators, and probe 1 to 2 absolute magnitudes fainter in the near-infrared than previous surveys. The effects of magnitude errors, redshift incompleteness and peculiar velocities have been taken into account and corrected throughout. Generally, the 6dFGS luminosity functions are in excellent agreement with those of similarly-sized surveys. Our data are of sufficient quality to demonstrate that a Schechter function is not an ideal fit to the true luminosity distribution, due to its inability to simultaneously match the faint end slope and rapid bright end decline. Integrated luminosity densities from the 6dFGS are consistent with an old stellar population and moderately declining star formation rate., Comment: 20 pages, 15 figures. MNRAS published. Replaces earlier version carrying a typo in Table 6. High resolution versions of the figures can be obtained from http://www.aao.gov.au/local/www/6df/Publications

The Wide Field Imager Lyman-Alpha Search (WFILAS) is a search for Lya emitting galaxies at z~5.7. Deep images from the Wide Field Imager (WFI) on the ESO/MPI 2.2m telescope have been used to detect 7 bright Lya emitting candidates in three fields covering 0.74 sq. degree on the sky. For this we used three narrowband (FWHM ~70A), one encompassing intermediate band (FWHM \~220A) and broadband B and R filters. One has thus far been spectroscopically confirmed as a Lya emitting galaxy at z=5.721 using FORS2 at the VLT. This galaxy shows a bright, well resolved asymmetric line profile, which is characteristic of Lya emitting galaxies. In one of our three fields, the Chandra Deep Field South (CDFS), we find an overdensity of Lya emitters in agreement with other surveys that have targeted this region. A statistically complete sample of our candidates probes the bright-end of the luminosity function, confirming earlier results from other smaller, deeper surveys., Comment: To appear in the proceedings for the Vth Marseille International Cosmology Conference: The Fabulous Destiny of Galaxies: Bridging Past and Present (5 pages). Requires mrs2005.sty, which is included

The 6dF Galaxy Survey is measuring around 150000 redshifts and 15000 peculiar velocities from galaxies over the southern sky at |b|>10 degrees. When complete, it will be the largest survey of its kind by more than an order of magnitude. Here we describe the characteristics of the Second Incremental Data Release (DR2) and provide an update of the survey. This follows earlier data made public in December 2002 and March 2004. A total of 83014 sources now have their spectra, redshifts, near-infrared and optical photometry available online and searchable through an SQL database at http://www-wfau.roe.ac.uk/6dFGS/., Comment: 11 pages, 7 figures. Submitted to PASA. High resolution versions of the figures can be obtained from http://www.aao.gov.au/local/www/6df/Publications

We report the spectroscopic confirmation of a compact \lya emitting galaxy at $z=5.721$. A FORS2 spectrum of the source shows a strong asymmetric line with a flux of 5$\times10^{-17}$ erg s$^{-1}$ cm$^{-2}$, making it one of the brightest \lya emitting galaxies at this redshift, and a line-of-sight velocity dispersion of 400 km s$^{-1}$. We also have a tentative detection of a second, narrower component that is redshifted by 400 km s$^{-1}$ with respect to the main peak. A FORS2 image shows that the source is compact, with a FWHM of 0\farcs5, which corresponds to 3.2 kpc at this redshift. This source is a brighter example of \object{J1236.8+6215} \citep{Dawson02}, another \lya\ emitting galaxy at $z\sim5.2$., Comment: Accepted by A&A, 4 pages, 4 figures. High resolution figures are available via http://www.mso.anu.edu.au/~westra/publications/

The 6dF Galaxy Survey (6dFGS) aims to measure the redshifts of around 150,000 galaxies, and the peculiar velocities of a 15,000-member sub-sample, over almost the entire southern sky. When complete, it will be the largest redshift survey of the nearby universe, reaching out to about z ~ 0.15, and more than an order of magnitude larger than any peculiar velocity survey to date. The targets are all galaxies brighter than K_tot = 12.75 in the 2MASS Extended Source Catalog (XSC), supplemented by 2MASS and SuperCOSMOS galaxies that complete the sample to limits of (H, J, r_F, b_J) = (13.05, 13.75, 15.6, 16.75). Central to the survey is the Six-Degree Field (6dF) multi-fibre spectrograph, an instrument able to record 150 simultaneous spectra over the 5.7-degree field of the UK Schmidt Telescope. An adaptive tiling algorithm has been employed to ensure around 95% fibering completeness over the 17046 sq.deg of the southern sky with | b | > 10 deg. Spectra are obtained in two observations using separate V and R gratings, that together give R ~ 1000 over at least 4000 -- 7500 Angstroms and signal-to-noise ratio ~10 per pixel. The 6dFGS database is available at http://www-wfau.roe.ac.uk/6dFGS/, with public data releases occuring after the completion of each third of the survey., Comment: 17 pages, 10 figures, submitted to MNRAS. Full resolution version of the paper available at http://www-wfau.roe.ac.uk/6dFGS/ and http://www.mso.anu.edu.au/6dFGS/