This paper presents the first major data release and survey description for the ANU WiFeS SuperNovA Programme. ANU WiFeS SuperNovA Programme is an ongoing supernova spectroscopy campaign utilising the Wide Field Spectrograph on the Australian National University 2.3-m telescope. The first and primary data release of this programme (AWSNAP-DR1) releases 357 spectra of 175 unique objects collected over 82 equivalent full nights of observing from 2012 July to 2015 August. These spectra have been made publicly available via the WISEREP supernova spectroscopy repository.

We analyse the ANU WiFeS SuperNovA Programme sample of Type Ia supernova spectra, including measurements of narrow sodium absorption features afforded by the high spectral resolution of the Wide Field Spectrograph instrument. In some cases, we were able to use the integral-field nature of the Wide Field Spectrograph instrument to measure the rotation velocity of the SN host galaxy near the SN location in order to obtain precision sodium absorption velocities. We also present an extensive time series of SN 2012dn, including a near-nebular spectrum which both confirms its ‘super-Chandrasekhar’ status and enables measurement of the sub-solar host metallicity at the SN site.

Pulsar Timing Array experiments exploit the clock-like behaviour of an array of millisecond pulsars, with the goal of detecting low-frequency gravitational waves. Pulsar Timing Array experiments have been in operation over the last decade, led by groups in Europe, Australia, and North America. These experiments use the most sensitive radio telescopes in the world, extremely precise pulsar timing models and sophisticated detection algorithms to increase the sensitivity of Pulsar Timing Arrays. No detection of gravitational waves has been made to date with this technique, but Pulsar Timing Array upper limits already contributed to rule out some models of galaxy formation. Moreover, a new generation of radio telescopes, such as the Five hundred metre Aperture Spherical Telescope and, in particular, the Square Kilometre Array, will offer a significant improvement to the Pulsar Timing Array sensitivity. In this article, we review the basic concepts of Pulsar Timing Array experiments, and discuss the latest results from the established Pulsar Timing Array collaborations.

We validate the baryonic Tully–Fisher (TF) relation by exploring the Tully–Fisher (TF) and BTF properties of optically and Hi-selected disk galaxies. The data includes galaxies from Sakai et al. (2000) calibrator sample, McGaugh et al. (2000: M2000) I-band sample, and 18 newly acquired Hi-selected field dwarf galaxies observed with the ANU 2.3-m telescope and the ATNF Parkes telescope (Gurovich 2005a).

As in M2000, we re-cast the TF and BTF relations as relationships between baryon mass and W20. First we report some numerical errors in M2000. Then, we calculate weighted bi-variate linear fits to the data, and finally we compare the fits of the intrinsically fainter dwarfs with the brighter galaxies of Sakai et al. (2000). With regards to the local calibrator disk galaxies of Sakai et al. (2000), our results suggest that the BTF relation is indeed tighter than the TF relation and that the slopes of the BTF relations are statistically flatter than the equivalent TF relations. Further, for the fainter galaxies which include the I-band M2000 and Hi-selected galaxies of Gurovich's sample, we calculate a break from a simple power law model because of what appears to be real cosmic scatter. Not withstanding this point, the BTF models are marginally better models than the equivalent TF ones with slightly smaller Χred2 values.

We investigate irradiation-driven mass transfer in cataclysmic variables in the presence of shielding of the radiation by an accretion disk. We have shown that the shielding can cause a temporal drop of 3–5 magnitudes in the brightness of systems with orbital periods shorter than about 4 hr. This provides a possible explanation for the brightness variations in the VY Scl stars.

Preliminary site testing results at Dome C (Antarctica) are presented, using both Automatic Weather Station (AWS) meteorological data (1986–1993) and Precipitable Water Vapour (PWV) measurements made by the authors. A comparison with the South Pole and other sites is made. The South Pole is a well established astrophysical observing site, where extremely good conditions are reported for a large fraction of time during the year. Dome C, where Italy and France are building a new scientific station, is a potential observing site in the millimetre and submillimetre range. AWS are operating at both sites and they have been continuously monitoring temperature, pressure and wind speed and direction for more than ten years. Site testing instruments are already operating at the South Pole (AASTO, Automated Astrophysical Site-Testing Observatory), while light experiments have been running at Dome C (APACHE, Antarctic Plateau Anisotropy CHasing Experiment) during summertime. A direct comparison between the two sites is planned in the near future, using the AASTO. The present analysis shows that the average wind speed is lower at Dome C (∼1 ms−1) than at the South Pole (∼2 ms−1), while temperature and PWV are comparable.

Luminous water maser emission in the 616–523 line at 22GHz has been detected from two dozen galaxies. In all cases the emission is confined to the nucleus and has been found only in AGN, in particular, in Type 2 Seyferts and LINERs. I argue that most of the observed megamaser sources are powered by X-ray irradiation of dense gas by the central engine. After briefly reviewing the physics of these X-Ray Dissociation Regions, I discuss in detail the observations of the maser disk in NGC 4258, its implications, and compare alternative models for the maser emission. I then discuss the observations of the other sources that have been imaged with VLBI to date, and how they do or do not fit into the framework of a thin, rotating disk, as in NGC 4258. Finally, I briefly discuss future prospects, especially the possibility of detecting other water maser transitions.

The long term goal of large-scale chemical tagging is to use stellar elemental abundances as a tracer of dispersed substructures of the Galactic disk. The identification of such lost stellar aggregates and the exploration of their chemical properties will be key in understanding the formation and evolution of the disk. Present day stellar structures such as open clusters and moving groups are the ideal testing grounds for the viability of chemical tagging, as they are believed to be the remnants of the original larger star-forming aggregates. Until recently, high accuracy elemental abundance studies of open clusters and moving groups having been lacking in the literature. In this paper we examine recent high resolution abundance studies of open clusters to explore the various abundance trends and reasses the prospects of large-scale chemical tagging.

A large scale 12CO J = 1 → 0 molecular line map of the Carina molecular cloud complex was obtained with the Mopra radio telescope in order to investigate its spatial and kinematic structure. The data show a complex velocity structure in two distinct cloud regions — the Northern and Southern Carina clouds. Two different clump identification methods (GAUSSCLUMPS and CLUMPFIND) were applied to the data. Though both algorithms find a similar clump mass spectral index (1.95 and 1.8, respectively), the properties of the clumps (mass, size, virial equilibrium) differ significantly. We discuss possible explanations for this discrepancy and question the validity of the Larson relations which could be an artifact of the limited spatial resolution and dynamic range of the observations.

In this review article, we discuss selected developments regarding the role of the equation of state in simulations of core-collapse supernovae. There are no first-principle calculations of the state of matter under supernova conditions since a wide range of conditions is covered, in terms of density, temperature, and isospin asymmetry. Instead, model equation of state are commonly employed in supernova studies. These can be divided into regimes with intrinsically different degrees of freedom: heavy nuclei at low temperatures, inhomogeneous nuclear matter where light and heavy nuclei coexist together with unbound nucleons, and the transition to homogeneous matter at high densities and temperatures. In this article, we discuss each of these phases with particular view on their role in supernova simulations.

Before and after every 12 hour synthesis observation, the Molonglo Observatory Synthesis Telescope (MOST) measures the flux densities of ∼5 compact extragalactic radio sources, chosen from a list of 55 calibrators. From 1984 to 1996, the MOST made some 58,000 such measurements. We have developed an algorithm to process this dataset to produce a light curve for each source spanning this thirteen-year period. We find that 18 of the 55 calibrators are variable, on time scales between one and ten years. There is the tendency for sources closer to the Galactic Plane to be more likely to vary, which suggests that the variability is a result of refractive scintillation in the Galactic interstellar medium. The sources with the flattest radio spectra show the highest levels of variability, an effect possibly resulting from differing orientations of the radio axes to the line of sight.

We have performed large-scale nucleosynthesis calculations within the high-entropy-wind (HEW) scenario of Type II supernovae. The primary aim was to constrain the conditions for the production of the classical ‘p-only’ isotopes of the light trans-Fe elements. We find, however, that for electron fractions in the range 0.458 ≤ Ye ≤ 0.478, sizeable abundances of p-, s- and r-process nuclei between 64Zn and 98Ru are coproduced in the HEW at low entropies (S ≤ 100) by a primary charged-particle process after an α-rich freezeout. With the above Ye–S correlation, most of the predicted isotopic abundance ratios within a given element, e.g. 64Zn(p)/70Zn(r) or 92Mo(p)/94Mo(p), as well as of neighboring elements, e.g. 70Ge(s + p)/74Se(p) or 74Se(p)/78Kr(p) agree with the observed Solar-System ratios. Taking the Mo isotopic chain as a particularly challenging example, we show that our HEW model can account for the production of all 7 stable isotopes, from ‘p-only’ 92Mo, via ‘s-only’ 96Mo up to ‘r-only’ 100Mo. Furthermore, our model is able to reproduce the isotopic composition of Mo in presolar SiC X-grains.

We present observations of 50 deg2 of the Mopra carbon monoxide (CO) survey of the Southern Galactic Plane, covering Galactic longitudes l = 300–350° and latitudes |b| ⩽ 0.5°. These data have been taken at 0.6 arcmin spatial resolution and 0.1 km s−1spectral resolution, providing an unprecedented view of the molecular clouds and gas of the Southern Galactic Plane in the 109–115 GHz J = 1–0 transitions of 12CO, 13CO, C18O, and C17O.

We present a series of velocity-integrated maps, spectra, and position-velocity plots that illustrate Galactic arm structures and trace masses on the order of ~106 M⊙ deg−2, and include a preliminary catalogue of C18O clumps located between l = 330–340°. Together with the information about the noise statistics of the survey, these data can be retrieved from the Mopra CO website and the PASA data store.

The emission nebula around the subdwarf B (sdB) star PHL 932 is currently classified as a planetary nebula (PN) in the literature. Based on a large body of multi-wavelength data, both new and previously published, we show here that this low-excitation nebula is in fact a small Strömgren sphere (Hii region) in the interstellar medium around this star. We summarise the properties of the nebula and its ionizing star, and discuss its evolutionary status. We find no compelling evidence for close binarity, arguing that PHL 932 is an ordinary sdB star. We also find that the emission nebulae around the hot DO stars PG 0108 + 101 and PG 0109 + 111 are also Strömgren spheres in the ISM, and along with PHL 932, are probably associated with the same extensive region of high-latitude molecular gas in Pisces–Pegasus.

IR spectroscopy in the range 12–230 μm with the SPace IR telescope for Cosmology and Astrophysics (SPICA) will reveal the physical processes governing the formation and evolution of galaxies and black holes through cosmic time, bridging the gap between the James Webb Space Telescope and the upcoming Extremely Large Telescopes at shorter wavelengths and the Atacama Large Millimeter Array at longer wavelengths. The SPICA, with its 2.5-m telescope actively cooled to below 8 K, will obtain the first spectroscopic determination, in the mid-IR rest-frame, of both the star-formation rate and black hole accretion rate histories of galaxies, reaching lookback times of 12 Gyr, for large statistically significant samples. Densities, temperatures, radiation fields, and gas-phase metallicities will be measured in dust-obscured galaxies and active galactic nuclei, sampling a large range in mass and luminosity, from faint local dwarf galaxies to luminous quasars in the distant Universe. Active galactic nuclei and starburst feedback and feeding mechanisms in distant galaxies will be uncovered through detailed measurements of molecular and atomic line profiles. The SPICA’s large-area deep spectrophotometric surveys will provide mid-IR spectra and continuum fluxes for unbiased samples of tens of thousands of galaxies, out to redshifts of z ~ 6.

This project uses the 2MASS all-sky image database to study the structure of galaxies over a range of luminosities, sizes and morphological types. This first paper in this series will outline the techniques, reliability and data products to our surface photometry program. Our program will analyze all acceptable galaxies (meeting our criteria for isolation from companions and bright stars) from the Revised Shapley–Ames and Uppsala galaxy catalogs. Resulting photometry and surface brightness profiles are released using a transparent scheme of data storage which includes not only all the processed data but knowledge of the processing steps and calibrating parameters.

The Carina Nebula is an extremely bright southern HII region embedded in a giant molecular cloud and contains some of the most massive stars known in our Galaxy. We are undertaking a multi-wavelength study of the Carina Nebula in order to examine the detailed kinematics and distribution of the molecular and ionised gas, and to look for further evidence of ongoing star formation. Here we present the results of the initial molecular cloud observations which were made by observing the 12CO(1−0) emission with the Mopra antenna. The observations reveal the clumpy morphology of the molecular gas, and allow us to identify many interesting regions for follow-up observations.

The Australian SKA Pathfinder (ASKAP) is being used to undertake a campaign to rapidly survey the sky in three frequency bands across its operational spectral range. The first pass of the Rapid ASKAP Continuum Survey (RACS) at 887.5 MHz in the low band has already been completed, with images, visibility datasets, and catalogues made available to the wider astronomical community through the CSIRO ASKAP Science Data Archive (CASDA). This work presents details of the second observing pass in the mid band at 1367.5 MHz, RACS-mid, and associated data release comprising images and visibility datasets covering the whole sky south of $\delta_{\text{J2000}}=+49^\circ$. This data release incorporates selective peeling to reduce artefacts around bright sources, as well as accurately modelled primary beam responses. The Stokes I images reach a median noise of 198 $\mu$Jy PSF$^{-1}$ with a declination-dependent angular resolution of 8.1–47.5 arcsec that fills a niche in the existing ecosystem of large-area astronomical surveys. We also supply Stokes V images after application of a widefield leakage correction, with a median noise of 165 $\mu$Jy PSF$^{-1}$. We find the residual leakage of Stokes I into V to be $\lesssim 0.9$–$2.4$% over the survey. This initial RACS-mid data release will be complemented by a future release comprising catalogues of the survey region. As with other RACS data releases, data products from this release will be made available through CASDA.

We briefly describe technical aspects and specifications of the new UKST Hα interference filter, which is probably the largest of its kind available in astronomy. Preliminary exposures show that the filter gives excellent imaging with high overall transmission and uniformity at Hα wavelengths. This is achieved over a circular area of about 305 mm diameter or about 5·7 degrees (the so called ‘clear aperture’). The prospects for the new UKST Hα survey of the southern Milky Way with this new filter are excellent.

Although originally classified as galaxies, Ultra-Compact Dwarfs (UCDs) have many properties in common with globular star clusters. The debate on the origin and nature of UCDs, and the recently discovered ultra-faint dwarf spheroidal (dSph) galaxies which contain very few stars, has motivated us to as the question ‘What is a galaxy?’ Our aim here is to promote further discussion of how to define a galaxy and, in particular, what separates it from a star cluster. Like most previous definitions, we adopt the requirement of gravitationally bound stellar system as a minimum. In order to distinguish a dwarf galaxy from a globular cluster, we discuss other possible requirements, such as a minimum size, a long two-body relaxation time a satellite system, the presence of complex stellar populations and non-baryonic dark matter. We briefly mention the implications of the adoption of each of these definitions. Some special cases of objects with a ambiguous nature are also discussed. Finally, we give our favoured criteria, and in the spirit of ‘collective wisdom’, invite readers to vote on their prefered definition of a galaxy via a dedicated website.

We describe a new low-frequency wideband radio survey of the southern sky. Observations covering 72–231 MHz and Declinations south of $+30^\circ$ have been performed with the Murchison Widefield Array “extended” Phase II configuration over 2018–2020 and will be processed to form data products including continuum and polarisation images and mosaics, multi-frequency catalogues, transient search data, and ionospheric measurements. From a pilot field described in this work, we publish an initial data release covering 1,447 $\mathrm{deg}^2$ over $4\,\mathrm{h}\leq \mathrm{RA}\leq 13\,\mathrm{h}$ , $-32.7^\circ \leq \mathrm{Dec} \leq -20.7^\circ$ . We process twenty frequency bands sampling 72–231 MHz, with a resolution of 2′–45′′, and produce a wideband source-finding image across 170–231 MHz with a root mean square noise of $1.27\pm0.15\,\mathrm{mJy\,beam}^{-1}$ . Source-finding yields 78,967 components, of which 71,320 are fitted spectrally. The catalogue has a completeness of 98% at ${{\sim}}50\,\mathrm{mJy}$ , and a reliability of 98.2% at $5\sigma$ rising to 99.7% at $7\sigma$ . A catalogue is available from Vizier; images are made available via the PASA datastore, AAO Data Central, and SkyView. This is the first in a series of data releases from the GLEAM-X survey.