Since their discovery in 1912, the origin of cosmic rays remains a mystery. The energy spectrum of cosmic rays suggests that these charged particles can be accelerated up to PeV energies within our Galaxy by so-called PeVatrons. As these charged particles propagate through the Galaxy, they are deflected by interstellar magnetic fields, as such we cannot trace them back. Instead, alternative...
The remarkable discovery by Y. Wang et al. (2021, MNRAS 502, 3294) of multiple scintillating AGN behind a nearby (within 20pc), long and narrow interstellar plasma filament (1.7 degrees by 4 arcmin on the sky) heralded a new era in studies of scintillating radio sources, made possible by widefield radio telescopes such as ASKAP. The finding has important implications for understanding the...
Compact Symmetric Objects, CSOs, are very compact, double-lobed radio galaxies, < 1 kiloparsec in extent. Understanding the population of CSOs has important implications for radio galaxy formation and evolution, but CSOs represent only a very small fraction (~5%) of bright, compact radio sources found in flux density limited surveys. The vast majority of sources are dominated by asymmetric...
Astrophysical jets powered by accretion onto supermassive black holes at the centre of galaxies are among the most energetic phenomena in our universe. Charged particles are accelerated along the jets to relativistic speeds, emitting synchrotron radiation observable at radio frequencies. Jets provide feedback and regulate star formation by interacting with the dense clumps of gas in their host...
We present photometric observations of SN2019vxm, a long-lasting, highly luminous Type IIn supernova, including a high-cadence rise captured by TESS. SN2019vxm has a broad range of electromagnetic detections ranging from Swift x-rays and ultraviolet through to near-infrared ground based surveys. By fitting a broken power-law model to the TESS light curve, we constrain the explosion time...
We present KAKAPO, the Kepler and K2 Analysis of Phast-evolving Objects pipeline for detecting transients in the Kepler/K2 space telescope. KAKAPO reliably recovers known transient events using effective Point-Spread Function Correlation matching and is currently searching for new events. In this poster we present the pipeline and the initial results.
An Active Galactic Nucleus (AGN) is the compact central region of a galaxy hosting a supermassive black hole that accretes gas and dust from its surroundings, often producing powerful outflows. Studying AGN provides critical insights into galaxy evolution and AGN-host interactions. Unlike the Northern Hemisphere, the Southern Sky remains underexplored in terms of AGN catalogues.
We present...
Among the mysteries of Fast Radio Bursts (FRBs) is how they direct, or 'beam' their energy. Despite observations of over 1000 FRBs from unique sources, the majority of the leading theories for emission mechanisms include some form of beaming, but this is often ignored for simplicity. Interpretations of features in the energy distribution, such as bimodality and broken power-laws implicitly...
The variable continuum emission from AGN can be used to probe the structure of their accretion disks via reverberation mapping analysis. Assuming a hot inner light source irradiating the outer accretion disk, time lags between light curves in different passbands reveal light-travel times between their emission regions. Previous work on several low-luminosity AGN found 3x longer lag times than...
When Wolf-Rayet stars are together with a massive companion in a close binary, their winds may collide to copiously form dust. This occurs at the shock of the wind-wind collision, and the orbital motion wraps this dust cone into a highly structure spiral nebula that expands away from the inner binary. State of the art ground-based and space telescopes (such as the VLT and JWST) are observing...
The origin of the slow solar wind (SSW) remains an open question in solar physics, with significant implications for understanding space weather and its impact on Earth. A leading hypothesis for the SSW origin is interchange reconnection at the interface between open and closed magnetic flux in the corona, suggesting that the closed flux near coronal hole boundaries influences the composition...
NASA's Solar Dynamics Observatory (SDO), launched in 2010, is a monitoring mission capturing full disk images of the Sun at a number of wavelengths with unprecedented spatial and temporal resolution. The SDO has generated an enormous amount of data over its operational lifetime, making it necessary to store the data in a searchable database for efficient access. We have established the...
Joyโs Law describes the systematic tilt of bipolar active regions on the Sun: the leading (prograde) magnetic polarity tends to emerge closer to the equator than the trailing (retrograde) polarity. This tilt increases with latitude and is attributed to the Coriolis force. In this study, we model the effect of the Coriolis force on a rising magnetic flux tube using a 3D Cartesian...
With the current upgrade of IceCube undergoing and IceCube Gen 2 on the way, along with KM3NeT in the Mediterranean Sea observing the most energetic neutrino event ever before even being finished, multi-messenger astronomy is becoming more and more prevalent than ever. However, one question remains unanswered: How many neutrino sources are there in the Universe? IceCube has provided evidence...
This poster showcases how interstellar absorption features in high-resolution optical spectra from the GALAH survey โ including neutral potassium (KโฏI) and diffuse interstellar bands (DIBs) โ can be used to trace the cold ISM across our Galaxy.
To highlight this amazing potential, we present first results by Nguyen, Buder et al. (in prep.), where we combine GALAH KโฏI absorption with GASKAP HI...
Debris discs are composed of planetesimal belts containing asteroids and comets that produce dust grains in mutual collisions. Radiation pressure forces acting upon the smallest of these grains can drive them onto eccentric orbits, spreading them far from the point of original production site of the planetesimal belt. Non-conservative forces, such as the P-R effect, can pull grains inwards...
Stellar feedback is thought to play a key role in regulating the gas-star formation cycle in galaxies, disrupting star-forming regions and driving outflows that can suppress star formation. However, most insights into these mechanisms come from starburst galaxies, limiting our broader understanding of their impact on galaxy evolution. In this talk, I will present the discovery of an ionized...
The origin of high-energy cosmic rays remains one of the most investigated open questions in astroparticle physics. The presence of the knee in the cosmic-ray energy spectrum is particularly interesting, as it indicates the maximum energy that cosmic rays within our Galaxy can be accelerated to. To search for possible sites of Galactic cosmic-ray acceleration, we can look for gamma rays that...
To reveal the nature of high-energy gamma-ray sources and to understand the associated emission and acceleration mechanisms, we need detailed models capable of reproducing the observed energy spectra and morphologies. Gamma rays can be produced in non-thermal radiation processes involving protons and electrons interacting with the interstellar medium (ISM). These protons and electrons...
Astronomical images can reveal circular structures arising from various phenomena. For instance, a shock propagating through the interstellar medium can sweep up material, creating voids, while relativistic electrons within shock and magnetic fields generate synchrotron radiation across the radio to X-ray bands. Commonly, these circular features are identified through a mostly manual...
In this talk, I will present a series of my recent work on HI kinematics, focusing on the Andromeda galaxy (M31), as one of the major key science projects of the Five-hundred-meter Aperture Spherical Radio Telescope (FAST). FASTโs unparalleled sensitivity delivers high-dynamic-range HI data that reveal remarkably complex kinematic structures, while simultaneously posing challenges for data...
The discovery of diffuse radio emission in galaxy clusters has been key to understanding the physical non-thermal processes shaping large-scale structures. For many years, galaxy groups were not contemplated as distinct astrophysical systems but rather as low-mass extensions of galaxy clusters. In reality, galaxy groups are common yet critical environments for studying galaxy evolution, the...
Spectral Energy Distribution fitting is a technique that forms the backbone for much of extragalactic analysis. From the vast samples of galaxies in modern galaxy redshift surveys, to the highest redshift galaxies from JWST, SED fitting is our best mechanism by which to derive properties like mass, star formation, and age of these galaxies.
The more we push these techniques, either in trying...
This poster presents a multi-frequency view of one of the largest and most evolved supernova remnants (SNRs) in the Large Magellanic Cloud (LMC), J0450-7050. As one of the Milky Way's closest galactic neighbours, the LMC provides a clear view of the entire SNR population in the galaxy, allowing us to analyse their properties, evolution, and impact on the surrounding galaxy environment....
Narrowband optical imaging is a useful tool for helping to characterise some high-energy sources, such as SNR and other sources producing gaseous emission lines. In particular, removal of continuum light from such narrowband images greatly improves the visibility of the emission line sources. Initial experiments in this regard, at Adelaide, will be described.
Extracting high quality calibrated lightcurves from TESS Full Frame Images can often be challenging due to high levels of scattered light, low spatial resolution, and broad bandpass. These challenges limit what phenomena that TESS can be used to study. The TESSreduce pipeline solves these challenges by providing flux calibrated PSF photometry for any TESS target with a single line of python...
The Transiting Exoplanet Survey Satellite (TESS) contains a wealth of information on asteroids. As irregularly shaped asteroids tumble across the TESS field their brightness changes periodically. To date TESS has observed thousands of asteroids at high cadence. With the TESSELLATE transient pipeline we have identified and extracted 10 minute cadence lightcurves of all asteroids brighter than...
Core Collapse Supernovae are powerful explosions marking the death of
massive stars. One of the most uncertain aspects of our understanding of the final stages of stellar evolution is the connection between the progenitor star, the type of explosion, and the resulting outcome, such as the formation of a compact object and/or an observable supernova. With the advent of ground-based optical...
Since its discovery by the Fermi-LAT space telescope, the galactic centre gamma-ray excess (GCE) has been the subject of intensive investigation in high-energy astrophysics. In this presentation, I will share progress on a current effort to model the GCE and determine if the Cherenkov Telescope Array Observatory (CTAO) will be able to distinguish between two prevalent hypotheses of the GCE...
The 21 cm line, produced by the hyperfine transition in the ground state of neutral hydrogen, makes an ideal tracer of the Epoch of Reionisation (EoR). Detecting this signal comes with many challenges, notably, strong foreground emissions and RFI, which are orders of magnitude brighter than the 21 cm signal.
Much of the work in EoR science involves methods to address these challenges. In this...
We investigate the baryonic Tully-Fisher relation using data from the WALLABY pilot survey, which includes a total sample of 2,352 galaxies. To accurately measure line widths of HI global profiles, we develop and apply a spectral profile fitting technique based on the Busy Function (Westmeier+2014), which effectively reduces systematic biases caused by noise peaks in low S/N spectra. This...
The problem of resolving both AGN and star formation feedback, operating through galactic-scale outflows, remains constrained by the limited spectral resolution of many ongoing galaxy surveys. Detecting outflows (as well as inflows) via emission-line kinematics from ionised species depends on multi-component fitting, which is highly sensitive to goodness-of-fit, overfitting criteria and...
Changes in the brightness of fast transients, observed over hours to months, can reveal the mass distribution of galaxies that lie along the line of sight. These galaxies deflect light from the source via gravitational microlensing. The difference in path length of individual rays, paired with variations in gravitational potential, change the arrival time of lensed light. These microlensing...
Studies of resolved kinematics can provide key insights into the impact of mergers on galaxy dynamical stability and gas turbulence. Studies of low redshift and simulated galaxies have found that merging events can cause enhanced star formation, complex, non-disc-like rotation and increased turbulence. Work has also been done to study the impact of mergers at higher redshift (z > 1), however...
The Evolutionary Map of the Universe (EMU) is currently conducting a radio-continuum survey with the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope. We can use the radio continuum galaxies from EMU to perform an observational test of General Relativity (GR) via cosmic magnification in the weak gravitational lensing regime; a key science goal of the cosmology project...
Mergers are fundamental to our understanding of the processes that drive the evolution of the structure and morphology of galaxies, star formation, AGN activity, and the redistribution of stellar mass in the Universe. Therefore, determining the fraction and properties of mergers across cosmic time is crucial for understanding the formation of the Universe we observe today. There are multiple...
Colliding black holes send ripples through space-time in the form of gravitational waves. The waves from the final ringing created by the disturbed remnant black hole settling into a stable state after the collision are encoded with clues about the nature of gravity. By analysing these waves in a method called black hole spectroscopy, we can test Einsteinโs theory of general relativity in...
Estimating supermassive black hole masses in AGN mostly relies on the virial method, which uses the radius-luminosity (R-L) relation to determine the radius of the broad line region (BLR). The R-L relation heavily depends on the assumption that the BLR is virialised. A volume-complete two-epoch Southern Sky AGN sample at $z<0.1$ and high-cadence monitoring of NGC 5548 have revealed significant...
Redshifts are crucial for nearly all extragalactic and cosmological studies. Upcoming wide-field surveys, such as the Evolutionary Map of the Universe (EMU), will catalogue millions of sources, making spectroscopic follow-ups unfeasible at scale. Though sensitive to band selection and availability, photometry yields redshifts (photo-$\textit{z}$s) for fainter sources while optimising telescope...
Accurate measurements of halo masses for galaxy groups are essential for understanding the connection between dark matter and baryons. We present two newly developed methods for improving halo mass estimates, calibrated using semi-analytical simulations. Relations are first calibrated against SHARK v2.0, and cross-validated with the independent SAGE model to assess sensitivity to underlying...
The 21 cm hydrogen line is a powerful probe of the intergalactic medium (IGM), enabling us to infer its thermal and ionisation history through statistical fluctuations measured via the power spectrum. In this talk, we present the deepest upper limits on the 21 cm power spectrum at redshifts z = 6.5, 6.8, and 7, derived from Murchison Widefield Array observations spanning 2013 to 2023. The...
SKA-Low construction is fully underway and making rapid progress. At this early stage, four stations are available for use as an integrated interferometric array. The SKA-Low Science Commissioning team has been able to demonstrate basic array calibration and has produced a first image from this initial test array. In this poster we will demonstrate imaging outcomes from the first four SKA-Low...
As operations for the SKA-Low telescope ramp up, scaling the operator team to support 24/7 observations presents both logistical and technical challenges. This talk outlines our implementation of a โfollow-the-sunโ style model between teams in Australia, South Africa and the UK, and the training strategy developed to ensure consistent knowledge transfer and operational readiness across sites....
The ASKAP Telescope is a cm-band synthesis imaging telescope operated by CSIRO at Inyarrimanha Ilgari Bundara, the CSIRO Murchison Radio-astronomy Observatory in Western Australia. Its innovative phased-array-feed (PAF) receivers give ASKAP the wide field-of-view that makes it excellent at conducting large-scale surveys of the sky. This comes, however, at the cost of high data rates....
The University of Southern Queensland operates Mt Kent Observatory as a robotic and remote-access astronomical and space research facility on behalf of Australian and international partners. The site hosts robotic telescopes for MINERVA-Australis exoplanet characterisation, for Stellar Observations Network Group asteroseismology, and for Shared Skies partnership remote-access astronomy. The...
The VAST Survey has been collecting data over the last four years using ASKAP to study radio transients. It has provided us with the most comprehensive radio time domain survey ever conducted, which gives us an invaluable opportunity to study radio transients, particularly Gamma-ray Burst (GRB) orphan afterglows, an area yet to be investigated using this dataset. GRBs are relativistic...
We present PyKOALA, an open-source Python package developed to streamline the reduction of integral field spectroscopy (IFS) data. Initially conceived as a specialist pipeline to complement the outputs of 2dfdr and enhance data reduction for the Kilofibre Optical AAT Lenslet Array (KOALA) Integral Field Unit (IFU), PyKOALA has evolved into a versatile, multi-instrument framework. It now offers...
The Evolutionary Map of the Universe (EMU) survey, conducted using the Australian Square Kilometre Array Pathfinder (ASKAP), aims to detect approximately 20 million radio galaxies, providing an unparalleled opportunity to explore galaxy evolution and uncover previously unknown astrophysical phenomena. However, the scale and complexity of this dataset go beyond the capabilities of traditional...
With the deprecation of Drupal 7 in January 2025, Data Central has fully transitioned the Lens platform to Django, a robust Python-based web framework. Originally developed in PHP and Drupal in 2015, Lens has long supported Time Allocation Committees (TAC) across major facilities such as the Anglo-Australian Telescope (AAT). Since being used for the 2024B semester on the ANU 2.3m Telescope,...
With ANU 2.3m Telescope observational data now being archived in the Data Central Archives system, observers can now receive their reduced data quicker than ever. As new observations come off the telescope, they are transferred into the Data Central Archives system where the data then gets reduced as part of the archival workflow. The implementation of the pyWiFeS pipeline automatically...
The successful automation of the ANU 2.3m telescope has unlocked the potential for extensive spectroscopic campaigns with the existing WiFeS integral field spectrograph. In this poster we describe a complementary near-infrared spectrograph concept to be located at the second Nasmyth focus. We present two conceptual designs for NIR spectrographs covering the J and H band, as well as highlight...
Data Central now provides multiple ways to access and use data hosted with us, whether via the web UI, the VO services or our science platform. In this talk, we will outline what your options are and which parts of your workflow would most benefit from which tools.
Optical communication is an alternative to radio for ground-to-space communication, providing more flexibility, larger bandwidth, and higher security. However, optical links are much more sensitive to the atmospheric turbulence. While downlinks can be corrected with adaptive optics (AO) at the ground terminal, uplinks present a more significant challenge due to power and space constraints. We...
The stellar populations and their distributions in and around galaxies record the evolutionary history of a galaxy. The gas from which stars form may have experienced dilution from pristine gas or enrichment from previous generations of stars. Alternatively, enriched gas may escape through stellar winds or AGN feedback in a shallow potential well. The structure and depth of the local...
Motivated by the need to explain why galaxy spin is more strongly correlated to internal properties of galaxies such as star formation rate and stellar population age, rather than mass or environment, we look at how bar formation can change the observed galaxy spin measurement within one effective radius. Using a suite of galaxy simulations, we find when bar formation occurs and identify the...
M67 is a dynamically evolved open cluster in the Milky Way, making it an ideal testbed for stellar and binary evolution theory. Due to its nearness and relatively low levels of dust in the line-of-sight, it has been extensively observed. We create $N$-body models of the old open cluster M67 (NGC 2682), taking into account its dynamical evolution as well as stellar and binary evolution of its...
In Galactic archaeology, the โalpha-kneeโ โ where the slope of the [ฮฑ/Fe]โ[Fe/H] relation changes โ is a chemical feature that serves as a powerful diagnostic of star formation histories in galaxies. The characteristics of this knee depend on the nucleosynthetic sources of the ฮฑ-elements (O, Mg, Si, S, and Ca) and their evolution relative to [Fe/H] enrichment, providing us with information on...
I present a novel approach to classify stellar streams and shells using the clustering algorithm AstroLink. This density-driven approach is applied to tidally disrupted stellar shells and streams formed in mock MW static haloes. AstroLink can identify the structures formed from the N-body simulations and provide clues to identifying streams and shells based on the ordered density distribution....
Neutral atomic hydrogen (HI) is a key component of the cold gas reservoir that fuels star formation in galaxies. However, global HI scaling relations often show significant scatter, partly because HI typically extends well beyond the stellar discs where most star formation occurs. A major limitation in resolving this connection has been the lack of spatially resolved HI data for large galaxy...
We present radio--continuum detections of the shells surrounding the well-known WN8 type Wolf-Rayet stars WR16 and WR40 at 943.5 MHz using the ASKAP EMU survey. These stars are easily identifiable by their surrounding outbursts of stellar material. WR16 is well known for its ring-like shell, whereas WR40's shell is elongated with non-uniform expansion. We analyse both stars and their shells as...
Veloce is a high-resolution (ฮป/โฮป = 80,000), stabilized, echelle spectrograph at the 3.9m Anglo-Australian Telescope, optimized for bright star observations. It covers 396โ940 nm across three spectral arms. A persistent issue has been electronic cross-talk in the red โRossoโ arm, where electronic ghost images appear in one quadrant due to bright pixels in another quadrant. This cross-talk is...
Cluster environments influence galaxy evolution by regulating star formation activity, notably through ram-pressure stripping (RPS), where the intracluster medium removes cold gas available for star formation as galaxies move through it. This may leave observable signatures, such as gas tails, truncated gas disks, and regions exhibiting intense star formation triggered by compression. Using...
We present an overview of the science program and instrument design for VelocePol - a polarimetric module for the Veloce spectrograph on the Anglo-Australian Telescope. This will provide much needed spectropolarimetric capabilities in the Southern sky for studies of stellar magnetism in the coming era of SKA-low and PLATO.
The PICSARR (Polarimeter using Imaging CMOS Sensor and Rotating Retarder) design was first tested in 2021. Several of these instruments have now been built and are used at several sites in Australia and the USA. Improvements in the latest versions enable observations of much fainter stars while still providing high-precision and wide wavelength coverage. These instruments allow small...
We have made the first complete survey of the linear polarization of all southern stars brighter than V=4. The 391 stars have been observed in the g' band to a median precision of 11 parts-per-million, more than 30 times better than previous incomplete surveys. Stars with significant polarization have been studied for variability. The observations allow mapping of the distribution of...
CTA-Pol is an optical polarimeter to deliver ancillary data for the Cherenkov Telescope Array Observatory (CTAO), the next-generation very high-energy gamma-ray observatory. Blazar flares combine increases in gamma-ray flux with changes in the fraction and orientation of visible-light polarisation. Other variable and transient sources to be targeted include gamma-ray bursts and tidal...
Data Central is the Science Platform for Australian Astronomy, providing multi-wavelength tools and services for both individual researchers and teams. This poster outlines what a Science Platform is, and how and why you can benefit from using our Science Platform.
