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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 per cent of the full survey. Galaxies included have the redshift range 0.004 < z < 0.092, a large mass range (7.6 < logM*/M☉ < 11.6), and star formation rates of ∼10-4 to ∼101M☉ yr-1. 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 (full width at half-maximum) over the 15 arcsec diameter field of view and spectral (kinematic) resolution of R = 4263 (σ = 30 km s-1) around Hα. The relative flux calibration is better than 5 per cent, and absolute flux calibration has an rms of 10 per cent. The data are presented online through the Australian Astronomical Observatory's Data Central. [ABSTRACT FROM AUTHOR]

ABSTRACT We report evidence of ordered orbital motion in luminous star-forming galaxies at z∼ 1.3. We present integral field spectroscopy (IFS) observations, performed with the OH Suppressing InfraRed Imaging Spectrograph (OSIRIS) system, assisted by laser guide star adaptive optics on the Keck telescope, of 13 star-forming galaxies selected from the WiggleZ Dark Energy Survey. Selected via ultraviolet and [O ii] emission, the large volume of the WiggleZ survey allows the selection of sources which have comparable intrinsic luminosity and stellar mass to IFS samples at z > 2. Multiple 1-2 kpc size subcomponents of emission, or 'clumps', are detected within the Hα spatial emission which extends over 6-10 kpc in four galaxies, resolved compact emission ( r < 3 kpc) is detected in five galaxies and extended regions of Hα emission are observed in the remaining four galaxies. We discuss these data in the context of different snapshots in a merger sequence and/or the evolutionary stages of coalescence of star-forming regions in an unstable disc. We find evidence of ordered orbital motion in galaxies as expected from disc models and the highest values of velocity dispersion (σ > 100 km s−1) in the most compact sources. This unique data set reveals that the most luminous star-forming galaxies at z > 1 are gaseous unstable discs indicating that a different mode of star formation could be feeding gas to galaxies at z > 1, and lending support to theories of cold dense gas flows from the intergalactic medium. [ABSTRACT FROM AUTHOR]

We report one of the most accurate measurements of the three-dimensional large-scale galaxy power spectrum achieved to date, using 56 159 redshifts of bright emission-line galaxies at effective redshift from the WiggleZ Dark Energy Survey at the Anglo-Australian Telescope. We describe in detail how we construct the survey selection function allowing for the varying target completeness and redshift completeness. We measure the total power with an accuracy of approximately 5 per cent in wavenumber bands of . A model power spectrum including non-linear corrections, combined with a linear galaxy bias factor and a simple model for redshift-space distortions, provides a good fit to our data for scales . The large-scale shape of the power spectrum is consistent with the best-fitting matter and baryon densities determined by observations of the cosmic microwave background radiation. By splitting the power spectrum measurement as a function of tangential and radial wavenumbers, we delineate the characteristic imprint of peculiar velocities. We use these to determine the growth rate of structure as a function of redshift in the range , including a data point at with an accuracy of 20 per cent. Our growth rate measurements are a close match to the self-consistent prediction of the Λ cold dark matter model. The WiggleZ survey data will allow a wide range of investigations into the cosmological model, cosmic expansion and growth history, topology of cosmic structure and Gaussianity of the initial conditions. Our calculation of the survey selection function will be released at a future date via our website wigglez.swin.edu.au. [ABSTRACT FROM AUTHOR]

The WiggleZ Dark Energy Survey is a survey of 240 000 emission-line galaxies in the distant Universe, measured with the AAOmega spectrograph on the 3.9-m Anglo-Australian Telescope (AAT). The primary aim of the survey is to precisely measure the scale of baryon acoustic oscillations (BAO) imprinted on the spatial distribution of these galaxies at look-back times of 4–8 Gyr. The target galaxies are selected using ultraviolet (UV) photometry from the Galaxy Evolution Explorer satellite, with a flux limit of . We also require that the targets are detected at optical wavelengths, specifically in the range . We use the Lyman break method applied to the UV colours, with additional optical colour limits, to select high-redshift galaxies. The galaxies generally have strong emission lines, permitting reliable redshift measurements in relatively short exposure times on the AAT. The median redshift of the galaxies is . The redshift range containing 90 per cent of the galaxies is . The survey will sample a volume of ∼1 Gpc3 over a projected area on the sky of 1000 deg2, with an average target density of 350 deg−2. Detailed forecasts indicate that the survey will measure the BAO scale to better than 2 per cent and the tangential and radial acoustic wave scales to approximately 3 and 5 per cent, respectively. Combining the WiggleZ constraints with existing cosmic microwave background measurements and the latest supernova data, the marginalized uncertainties in the cosmological model are expected to be and (for a constant w model). The WiggleZ measurement of w will constitute a robust, precise and independent test of dark energy models. This paper provides a detailed description of the survey and its design, as well as the spectroscopic observations, data reduction and redshift measurement techniques employed. It also presents an analysis of the properties of the target galaxies, including emission-line diagnostics which show that they are mostly extreme starburst galaxies, and Hubble Space Telescope images, which show that they contain a high fraction of interacting or distorted systems. In conjunction with this paper, we make a public data release of data for the first 100 000 galaxies measured for the project. [ABSTRACT FROM AUTHOR]

The WiggleZ Dark Energy Survey is a large-scale structure survey of intermediate-redshift ultraviolet-selected (UV-selected) emission-line galaxies scheduled to cover 1000 deg2, spanning a broad redshift range . The main scientific goal of the survey is the measurement of baryon acoustic oscillations (BAO) in the galaxy clustering pattern at a significantly higher redshift than previous studies. The BAO may be applied as a standard cosmological ruler to constrain dark energy models. Based on the first 20 per cent of the data set, we present initial results concerning the small-scale clustering of the WiggleZ targets, together with survey forecasts. The WiggleZ galaxy population possesses a clustering length Mpc, which is significantly larger than UV-selected samples, with a slope . This clustering length is comparable to Lyman-break galaxies with similar UV luminosities. The clustering strength of the sample increases with optical luminosity, UV luminosity and reddening rest-frame colour. The full survey, scheduled for completion in 2010, will map an effective volume Gpc3 (evaluated at a scale ) and will measure the angular diameter distance and Hubble expansion rates in three redshift bins with accuracies of ≈5 per cent. We will determine the value of a constant dark energy equation-of-state parameter, wcons, with a higher precision than existing supernovae observations using an entirely independent technique. The WiggleZ and supernova measurements lie in highly complementary directions in the plane of wcons and the matter density Ωm. The forecast using the full combination of WiggleZ, supernova and cosmic microwave background (CMB) data sets is a marginalized error , providing a robust and precise measurement of the properties of dark energy including cross-checking of systematic errors. [ABSTRACT FROM AUTHOR]

We have undertaken a pilot survey for faint quasi-stellar objects (QSOs) in the UKIRT Infrared Deep Survey (UKIDSS) Ultra Deep Survey (UDS) Field using the KX selection technique. These observations exploit the very deep near-infrared and optical imaging of this field from United Kingdom Infrared Telescope (UKIRT) and Subaru to select candidate QSOs based on their VJK colours and morphologies. We determined redshifts for 426 candidates using the AAOmega spectrograph on the Anglo-Australian Telescope in service time. We identify 17 QSOs in this pilot survey at z= 1.57–3.29. We combine our sample with an X-ray-selected sample of QSOs in the same field (a large fraction of which also comply with our KX selection) to constrain the surface density of QSOs with K≤ 20, deriving limits on the likely surface density of 85–150 deg−2. We use the good image quality available from our near-infrared imaging to detect a spatially extended component of the QSO light which probably represents the host galaxies. We also use our sample to investigate routes to improve the selection of KX QSOs at faint limits in the face of the significant contamination by compact, foreground galaxies. The brightest examples from our combined QSO sample will be used in conjunction with a large Very Large Telescope VIMOS spectroscopic survey of high-redshift galaxies in this region to study the structures inhabited by gas, galaxies and growing supermassive black holes at high redshifts in the UKIDSS UDS. [ABSTRACT FROM AUTHOR]