Search Publications
Measuring the stellar and planetary parameters of the 51 Eridani system
Mann, Andrew W.; von Braun, Kaspar; Schaefer, Gail +3 more
In order to study exoplanets, a comprehensive characterisation of the fundamental properties of the host stars – such as angular diameter, temperature, luminosity, and age, is essential, as the formation and evolution of exoplanets are directly influenced by the host stars at various points in time. In this paper, we present interferometric observ…
Galaxy spin direction asymmetry in JWST deep fields
Shamir, Lior
The unprecedented imaging power of James Webb Space Telescope (JWST) provides new abilities to observe the shapes of objects in the early Universe in a way that has not been possible before. Recently, JWST acquired a deep field image inside the same field imaged in the past as the Hubble Space Telescope (HST) Ultra Deep Field. Computer-based quant…
New radio continuum study of the large magellanic cloud supernova remnant N49
Sasaki, Manami; Haberl, Frank; Kavanagh, Patrick +12 more
We present new Australia Telescope Compact Array (ATCA) radio observations towards N 49, one of the brightest extragalactic supernova remnants (SNRs) located in the Large Magellanic Cloud (LMC). Our new and archival ATCA radio observations were analysed along with Chandra X-ray data. These observations show a prominent 'bullet' shaped feature beyo…
A jet-induced shock in a young, powerful radio galaxy at z = 3.00
Noirot, Gaël; Gupta, Anshu; Emonts, Bjorn +9 more
The bright radio source, GLEAM J091734 - 001243 (hereafter GLEAM J0917 - 0012), was previously selected as a candidate ultra-high redshift ( z > 5 ) radio galaxy due to its compact radio size and faint magnitude ( K(AB)=22.7 ). Its redshift was not conclusively determined from follow-up millimetre and near-infrared spectroscopy. Here we present…
MOSEL survey: Unwrapping the Epoch of Reionisation through mimic galaxies at Cosmic Noon
Harshan, Anishya; Gupta, Anshu; Trott, Cathryn M. +4 more
The nature of the first galaxies that reionised the universe during the Epoch of Reionisation (EoR) remains unclear. Attempts to directly determine spectral properties of these early galaxies are affected by both limited photometric constraints across the spectrum and by the opacity of the intergalactic medium to the Lyman Continuum (LyC) at high …
HST WFC3/Grism observations of the candidate ultra-high-redshift radio galaxy GLEAM J0917-0012
Seymour, N.; Drouart, G.; Vernet, J. D. R. +11 more
We present Hubble Space Telescope Wide Field Camera 3 photometric and grism observations of the candidate ultra-high-redshift ( $z>7$ ) radio galaxy, GLEAM J0917-0012. This radio source was selected due to the curvature in its 70-230 MHz, low-frequency Murchison Widefield Array radio spectrum and its faintness in K-band. Follow-up spectroscopic…
Large-scale asymmetry in galaxy spin directions: evidence from the Southern hemisphere
Shamir, Lior
Recent observations using several different telescopes and sky surveys showed patterns of asymmetry in the distribution of galaxies by their spin directions as observed from Earth. These studies were done with data imaged from the Northern hemisphere, showing excellent agreement between different telescopes and different analysis methods. Here, da…
Absolute V-band magnitudes and mass-to-light ratios of Galactic globular clusters
Hilker, M.; Baumgardt, H.; Sollima, A.
We have used Hubble Space Telescope and ground-based photometry to determine total V-band magnitudes and mass-to-light ratios of more than 150 Galactic globular clusters. We do this by summing up the magnitudes of their individual member stars, using colour-magnitude information, Gaia DR2 proper motions, and radial velocities to distinguish cluste…
Galaxy spin direction distribution in HST and SDSS show similar large-scale asymmetry
Shamir, Lior
Several recent observations using large data sets of galaxies showed non-random distribution of the spin directions of spiral galaxies, even when the galaxies are too far from each other to have gravitational interaction. Here, a data set of$\sim8.7\cdot10^3$spiral galaxies imaged byHubble Space Telescope(HST) is used to test and profile a possibl…
ASKAP reveals giant radio halos in two merging SPT galaxy clusters
Johnston-Hollitt, Melanie; Akamatsu, Hiroki; Hodgson, Torrance +4 more
Early science observations from the Australian Square Kilometre Array Pathfinder (ASKAP) have revealed clear signals of diffuse radio emission associated with two clusters detected by the South Pole Telescope via their Sunyaev Zel'dovich signal: SPT CLJ0553-3342 (MACS J0553.4-3342) and SPT CLJ0638-5358 (Abell S0592) are both high-mass lensing clus…