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 /M ) < 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 /M ) > 11), the velocity dispersion strongly increases towards the centre, whereas below log(M /M ) < 10 we find no evidence for a clear increase in the central velocity dispersion. This suggests a transition mass around log(M /M ) ∼ 10 for galaxies with or without a dispersion-dominated bulge.

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 M * / M < 11.6), and star-formation rates of ∼ 10 −4 to ∼ 10 1 M yr −1 . For each galaxy, we include two spectral cubes and a set of spatially resolved 2D maps: single-and multicomponent 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-atmosphericrefraction 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 (σ = 30 km s −1 ) around Hα. The relative flux calibration is better than 5% and absolute flux calibration better than ±0.22 mag, with the latter estimate limited by galaxy photometry. The data are presented online through the Australian Astronomical Observatory's Data Central.

The Hubble Deep Field South (HDF-S) Hubble Space Telescope (HST) observations are expected to begin in October 1998. We present a composite spectrum of the QSO in the HDF-S field covering UV/optical/near IR wavelengths, obtained by combining data from the Australian National University 2.3m Telescope with STIS on the Hubble Space Telescope (HST) 1 . This intermediate resolution spectrum covers the range 1600-10000Å and allows us to derive some basic information on the intervening absorption systems which will be important in planning future higher resolution studies of this QSO.The QSO J2233−606 coordinates are 22:33:37.6 −60:33:29 (J2000), the magnitude is B=17.5, and its redshift is z em = 2.238, derived by simultaneously fitting several emission lines. The spectral index is α = −0.7 ± 0.1, measured between the Lyman-α and Mg II emission lines. Many absorption systems are present, including systems with metal lines redwards of the Lyman-α emission line at z abs = 2.204, 1.942, 1.870, 1.787 and a few very strong Lyman-α features at z abs = 2.077, 1.928, without similarly strong metal lines. There is a conspicuous Lyman limit (LL) absorption system that is most likely associated with the z abs = 1.942 system with a neutral hydrogen column density of N HI = (3.1 ± 1.0) × 10 17 cm −2 . There is some evidence for the presence of a second LL absorber just to blue of the conspicuous system at z = 1.870. We have employed a new technique, based on an analysis of the shape of the observed spectrum in the region of the LL absorption, to explore the properties of the gas. We tentatively conclude that this system might have suitable characteristics for measuring the deuterium-to-hydrogen (D/H) ratio.

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