CTAO Status and Updates

• Gavin Rowell (School of Physical Sciences, University of Adelaide)

I will present a brief status report on CTAO.

Transient Science

• Gavin Rowell (School of Physical Sciences, University of Adelaide)

An Introduction to Contemporary Gravitational-Wave Science

• Nir Guttman

A concise overview of gravitational-wave science: the nature of gravitational waves and how we detect them, highlighting results from the latest catalog as the field shifts from first detections to using gravitational waves as precision probes of the universe.

Flexible modelling of gravitational-wave signals using Gaussian processes

• Lachlan Passenger

Bayesian statistical methods form the foundation for signal extraction from gravitational-wave data. Commonly, these methods assume a functional form for the signal, and provide estimates for the function’s parameters. Gaussian processes allow for flexible modelling of signals, for which the functional form is unknown but the overall structure is. I’ll describe the kinds of problems that are well-suited to Gaussian processes, as well as several applications to gravitational-wave data.

Follow up of Transients with the CTAO

• Sabrina Einecke (The University of Adelaide, Australia)

Progress on SST QCAM-i data analysis from Tenerife

• Simon Lee (School of Physical Sciences, University of Adelaide)

In July 2025 the initial build of a quarter camera (QCAM-i) designed for the Cherenkov Telescope Array Observatory (CTAO) Small Sized Telescope (SST) design was tested observing the sky above Tenerife, Canary Islands. This was the first field test of the camera hardware which will eventually be used across dozens of SSTs at CTAO-South in Chile. Dark field observations (pointed away from known gamma-ray sources) were taken to collect cosmic-ray shower images, which can be compared with Monte Carlo simulations for validation. This talk will present recent progress in the processing and analysis of QCAM-i data, including charge extraction performance, calibration methods, and comparisons with simulations.

Approaches on Long-term Lightcurves of Blazars for Theoretical Modelling Comparison

• Cyrus Walther (TU Dortmund University)

Modeling the emission of gamma-ray photons of blazars is often performed as a core step in short-term IACT blazar analyses. It is, however, of interest to analyze the temporal component of blazar emission on a long-term scale, which yields insights into temporal aspects of acceleration mechanisms through comparison with theoretical modeling. This requires, on one hand, a consistent and reliable method for analyzing large amounts of data with reproducible configuration in a shorter timeframe. For this purpose, the database-driven automation tool autoMAGIC was developed for data from the MAGIC telescopes. On the other hand, a theoretical modeling tool is required to provide theoretical temporal simulations for comparison with long-term lightcurve data. Hence, this use case is being developed based on the cosmic-ray propagation framework, CRPropa. This talk presents the autoMAGIC structure and an example analysis performed with autoMAGIC, demonstrating reliability compared to established methods as well as the outline and possible challenges in the comparison with theoretical modeling.

Modelling the unknown with CTAO: Investigating indirect WIMP dark matter search systematics

• Liam Pinchbeck (Monash University)

Dark matter is one of the most important, elusive and enduring mysteries of physics in the last century. Gamma ray astronomy offers a possible avenue to determine dark matter's particle nature through observation of gamma ray by-products of its annihilation or decay. However, it is challenging to formulate a robust dark matter search given our lack of knowledge on dark matter physics and background contributions around targets of interest. In this talk, I describe a robust, flexible framework that can account for many of these systematics. In order to achieve this, we model the final state output contributions and differential J factor maps in a model-independent way using future data from the Cherenkov Telescope Array observatory and all of the pertinent background parameters of interest utilising normalising flows.

Where do cosmic rays go to die?

• Roland Crocker (Research School of Astronomy and Astrophysics, Australian National University)

Cosmic rays that escape from star-forming galaxies may significantly influence the dynamics or thermodynamics of the circumgalactic gas reservoir that sustains star formation over long timescales. I will explain how our semi-analytic model for cosmic ray transport and energy loss in the CGM can, in combination with empirical inputs, constrain the importance of cosmic rays in the CGM environment and inform the CRs' long-term fate.

Modelling Millisecond Pulsars and CTAO's Detection Prospects

• Hayden James (Adelaide University)

The upcoming Cherenkov Telescope Array Observatory (CTAO) presents a unique opportunity to probe the as-yet unexplained Fermi-LAT galactic centre gamma-ray excess (GCE). I will present results from my research that show CTAO may be able to distinguish between two different origins of the GCE.

Update on Reconstruction Performance with Truncated Images

• Violet Harvey (The University of Adelaide)

Deep Learning and Muon Physics with IACTs

• Lydia Castellucci (Adelaide University)

At very high energies, there is a deficiency in the number of muons produced in hadronic extensive air showers (EAS) in simulated interaction models compared to experimental measurements. Imaging atmospheric Cherenkov telescopes (IACTs) can be used to study this ‘muon puzzle’. These telescopes detect the resultant Cherenkov light emitted from the interaction of cosmic rays with atmospheric nuclei. To study this discrepancy, muons must be efficiently identified with sufficient statistics to be able to distinguish different shower models. Presented in this talk is an introduction to how muons are measured with IACTs, the properties of air showers and muons that are useful to develop an efficient model, and the machine learning techniques that will be used.

Supernova remnants in the Large Magellanic Cloud

• Zachary Smeaton (WSU)

The Large Magellanic Cloud (LMC) is one of our nearest galactic neighbours and has been well-surveyed at multiple frequencies. A recent MeerKAT radio-continuum survey provides unprecedented sensitivity and resolution of the LMC, revealing its supernova remnant (SNR) population in greater detail than previously seen. Combining this new data with previous multi-frequency surveys, I have characterized the entire visible LMC SNR population. This catalogue enables statistical analysis of morphological and spectral properties including diameter, ovality, age, and spectral indices. Statistical tests, such as comparing core-collapse and thermonuclear SNR populations, can help reveal distinctive evolutionary patterns. This work provides a comprehensive radio foundation for understanding the LMC SNR population, complementing future multi-frequency observations and surveys, such as the upcoming CTA surveys.

ASKAP Update

• Miroslav Filipovic (Western Sydney University)

These are golden days for radio-astronomy... A number of new cool discoveries at are steadyly coming from the new generation of radio telescopes. I will update CTA-Oz with the latest results in this space.

StarFiSH and the CTAO: Update

• Aaron Bradley (WSU)

We present an update on the previously discussed StarFiSH legacy survey. StarFiSH is a 7 mm dense gas survey that mapped the fourth quadrant Galactic Plane. The data have remained relatively untouched, and would be a crucial ancillary data set for high-energy Galactic targets for the CTA. In this update, we provide an update of the ongoing collaborations for the reduction of the data, as well as some tantalising 'first-look' images.

SKAO Science Operations Update

• Jess Broderick (SKAO)

The Square Kilometre Array Observatory (SKAO) Science Operations Team is focused on the development and implementation of various workflows and procedures to ensure that SKA-Low and SKA-Mid will be operationally ready for transformational science. In this talk, I will give an update on the telescope capability rollout, as well as plans for the upcoming Science Verification phase.

Progress on Optical Polarization Measurements

• Ahmad Al-khalaila (WSU)

The work focused on measuring the linear polarization of bright and faint stars to validate the instrument’s performance and refine the data-reduction pipeline. Using a sequence of retarder-angle images, we calculated the polarization fraction and angle, tested calibration consistency, and automated key steps in the Python-based workflow. These results establish a reliable framework for upcoming blazar observations and multi-site CTApol integration.

AAL Update

• James Murray (Astronomy Australia Limited)

Colloquium: TeV Gamma-Ray Astronomy with the Cherenkov Telescope Array Observatory (CTAO)

• Gavin Rowell (School of Physical Sciences, University of Adelaide)

The CTAO represents the next major step in TeV gamma-ray astronomy. CTAO is now under construction at two sites - a northern site at La Palma, Spain, and a southern site at Paranal, Chile. Together, the CTAO's North and South arrays will provide an order of magnitude improvement in performance beyond current instruments (like HESS and MAGIC) to unveil the gamma-ray sky like never before. Australia has vital roles in CTAO construction, contributing funding (ARC, NCRIS plus seven universities including Monash Uni.), hardware towards telescope cameras, and expertise in analysis software development. Australian CTAO Consortium members are actively working on challenges in astrophysics and astroparticle physics that CTAO aims to tackle. Such challenges include the origin of cosmic rays, relativistic flows, extreme transients, and the nature of dark matter. This talk will provide an update on the status of CTAO, and the various roles of Australian teams.