Centre for Astrophysics and Supercomputing

• Internal
• Swinburne Astronomy Online
• Supercomputing

Potential PhD Topics

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PhD Supervisors

Below are listed those CAS staff who may be currently looking for PhD students.

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PhD Projects

Prof. Matthew Bailes

• Advanced Signal Processing for Fast Radio Burst and Pulsar Discovery

Prof. Chris Blake

• No projects offered at this time

Prof. Jean Brodie

• No projects offered at this time

A.Prof. Michelle Cluver

• No projects offered at this time

Prof. Jeff Cooke

• Observing the most extreme explosions and distant galaxy interactions to test fundamental theories
• The Deeper, Wider, Faster program: Discovering the fastest bursts in the Universe

Prof. Darren Croton

• No projects offered at this time

Dr. Rebecca Davies

• No projects offered at this time

Prof. Adam Deller

• Advanced Signal Processing for Fast Radio Burst and Pulsar Discovery

Prof. Alan Duffy

• No projects offered at this time

A.Prof. Deanne Fisher

• How Do Exploding Stars Reshape Galaxy Evolution?

Dr. Chris Flynn

• No projects offered at this time

Prof. Christropher Fluke

• Improving Space Domain Awareness with Astronomy-inspired solutions

Prof. Duncan Forbes

• Ultra diffuse galaxies: galaxies at the extremes

Prof. Karl Glazebrook

• Precise galaxy kinematics at cosmic noon and beyond

Prof. Alister Graham

• The missing population of intermediate mass black holes
• Galaxy Structure and massive black holes

Prof. Jarrod Hurley

• No projects offered at this time

A.Prof. Glenn Kacprzak

• Understanding gas flows in and around galaxies

Prof. Virginia Kilborn

• No projects offered at this time

A.Prof. Ivo Labbe

• No projects offered at this time

Dr. Ben McAllister

• Axion Dark Matter Detection

Dr. Anais Möller

• No projects offered at this time

Prof. Jeremy Mould

• No projects offered at this time

Prof. Michael Murphy

• Do the fundamental constants of nature actually vary?
• Can we watch the Universe expand in real time?
• Understanding gas flows in and around galaxies

Dr. Themiya Nanayakkara

• No projects offered at this time

Dr. Jade Powell

• Searching for explosive new sources of gravitational waves

Dr Daniel Reardon

• Mapping the gravitational wave sky with pulsar timing arrays

Prof. Emma Ryan-Weber

• No projects offered at this time

Prof. Ryan Shannon

• Mapping the gravitational wave sky with pulsar timing arrays

Dr. Simon Stevenson

• No projects available at this time

A.Prof. Edward N. Taylor

• No projects offered at this time

Dr. Sara Webb

• Improving Space Domain Awareness with Astronomy-inspired solutions
• Characterising the subminute optical transient sky

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Project Descriptions

Supervisors: Prof. Matthew Bailes and Prof. Adam Deller

Large radio telescopes are increasingly affected by radio frequency interference that masks the faint signals seen from pulsars and Fast Radio Bursts. The computational challenges of dispersed signal detection are challenging enough to prohibit real-time removal of interference, and astronomers have to try to come up with post-detection solutions that compromise our observations. In this project, we will explore techniques aimed at the real-time removal of interference, to improve pulsar and FRB detection rates. We will start with archival datasets and take baseband data from the Parkes and MeerKAT radio telescopes to develop new algorithms that future instruments will hopefully use to purify the radio sky.

Supervisors: Prof. Jeff Cooke

Two of the most extreme explosions in the Universe are superluminous supernovae and gamma-ray bursts. These events are so luminous that they can be detected across the Universe and all the way back to a time when the first generation of stars formed shortly after the Big Bang. We currently do not know what types of stars create these events, their mass, nor the mechanisms behind their extreme explosion energies. On a separate topic, we all learn that giant molecular clouds of gas and dust collapse to form stars. The timescale in which they collapse is core to our understanding of the formation of stars and galaxies and the evolution of the Universe, yet the timescale of their collapse has never been directly observed.

This project aims to provide the first direct observations to answer the above long-standing questions. The student will use existing, and acquire new, Hubble Space Telescope, James Webb Space Telescope, and Keck observations and apply an innovative method analysing interacting host galaxies to make the first direct measurements of the time it takes for gas clouds to collapse to form stars, and the lifetimes (and, thus, mass) of the specific stars that die as superluminous supernovae or gamma-ray bursts. The spectroscopy gathered in this project will be essential for theoretical models to understand the explosion mechanisms behind superluminous supernovae and gamma-ray bursts.

Supervisors: Prof. Jeff Cooke

The Swinburne-led Deeper, Wider, Faster (DWF) program is the first all-wavelength program designed to detect and rapidly follow up the fastest transients in the Universe, such fast radio bursts, supernova shock breakouts, all types of gamma-ray bursts, kilonovae, flare stars, and many other events, including the discovery of unknown classes. DWF is the world's largest collaboration of telescopes, with over 90 major observatories on every continent and in space. DWF coordinates wide-field radio through gamma-ray telescopes, such as Parkes, ASKAP (radio), the South Pole Telescope (mm), CTIO DECam (optical), Astrosat (UV), HXMT (X-ray), and NASA Swift, HESS (gamma-ray), to observe the same fields at the same time. The data are processed in real time either at the telescopes or using the Swinburne supercomputer and transients are identified within minutes of their outbursts in our Swinburne Mission Control room. Fast identification of the transients enables rapid-response spectroscopic and imaging follow up observations before the events fade using the world’s largest telescopes, such as Keck, the VLT, Gemini-South, SALT, the AAT (optical) and ATCA (radio), and NASA Swift (high-energy). Finally, our network of 1-2 metre-class telescopes located worldwide provide simultaneous and/or follow-up imaging and spectroscopy to monitor the events.

The student will participate in the DWF coordinated observing runs and help analyse the data to produce leading transient science. Depending on the interests and experience of the student, the project will involve (1) developing techniques to search the deep optical data to investigate known fast transients and potentially discover new classes of transients, (2) cross-matching multi-wavelength data to extend our knowledge of fast transients and the behavior of new event types, (3) progressing real-time fast transient identification and predictive capabilities using machine and deep learning techniques, and (4) enhancing and accelerating transient discovery by progressing data visualisation and data sonification techniques, including virtual reality and augmented reality analyses.

Supervisors: A.Prof. Deanne Fisher

Supernovae are among the most energetic events in the universe, typically outshining the galaxy they occur in. In starburst galaxies, clusters of supernovae explode in the disk, the combined energy and momentum pushes gas up out of the spiral galaxy and into the halo above the disk. This changes the properties of the galaxy, and is considered by most theories to be a linchpin that regulates the growth of galaxies. We view this as faint filaments of gas that extends above star forming galaxies. In this project we will study this gas. The physical properties of the gas directly relate to the physical models of how these large outflows of gas evolve and shape outflows. We will use data James Webb Space Telescope (dust), ALMA (molecular gas), MeerKAT (atomic gas) and Keck & VLT (optical ionised gas) to study the outflowing gas in multiple phases. Outflows have never been studied with this level of data on this many targets. There is scope for many different directions within this project, I will work with you to find what you’re most interested in. The student will be part of an international team that includes astronomers in Europe, USA and Australia. At Swinburne they will work in a team of other PhD students and postdocs, along with myself.

Further information:

• Galactic winds dictating galaxy evolution. A 20 minut lecture by L. Zscaechner.
• How Feedback Shapes Galaxy Evolution. 1 hour lecture by Prof Christy Tremonti.

Supervisors: Prof. Christopher Fluke and Dr. Sara Webb

At start of your PhD, there will be approximately 10,000 active or operating satellites orbiting the Earth. By the end of your PhD, that number will be approaching 50,000.

There is an urgent need for improved Space Domain Awareness (SDA), including the detection, characterisation, and simulation of increasingly complex, real-time orbital scenarios. The risk of doing nothing is a catastrophic loss of critical orbital zones for communication, navigation, and Earth climate monitoring due to a runaway destructive cascade that could start with a single satellite-satellite collision. There is substantial untapped potential for astronomers to contribute data and knowledge to international SDA efforts. In this PhD project, you will identify, research, develop, implement, and evaluate novel astronomy-inspired approaches to SDA. You can expect to use concepts and solutions from artificial intelligence, machine learning, human-machine teaming, and advanced immersive and collaborative data visualisation.

Supervisors: Prof. Duncan Forbes

In 2015 a new class of galaxy was discovered - the ghostly Ultra Diffuse Galaxy (UDG). Such galaxies have the same total luminosity as a dwarf galaxy but some reveal a halo of dark matter similar to that of a giant galaxy making them 99% dark matter! Since their discovery they remain a mystery and a challenge to theories of galaxy formation. This PhD project aims to discover more UDGs from deep imaging, determine their stellar population and dynamical properties, and compare them with the latest theoretical models. This project is an observational one, using new data from the world's largest telescopes (Keck and the VLTs) and involving colleagues in California.

Image caption: Ultra Diffuse Galaxies have the same total luminosity as a dwarf galaxy but the same total mass as a giant galaxy. Some UDGs are 99% composed of dark matter and we don't know why! (Credit: Schoening/Harvey/van Dokkum/NASA/ESA Hubble Space Telescope.

Supervisors: Prof. Karl Glazebrook

Galaxy kinematics in the high redshift Universe tells us about the evolution of cold dark matter halos and the accumulation of baryons in their centre to make galaxies. These measurements provide for fundamental insights into both cosmology and galaxy evolution models. JWST promises a revolution here thanks to its extreme sensitivity and the high resolution of its images. We are able to measure the motions of stars and gas within galaxies across much greater radial extents and to higher redshifts than were previously possible with the largest ground based telescopes. In this PhD you will learn to work with JWST data from the innovative MSA3D survey, using a ‘slit stepping’ technique we have been able to construct integral field spectroscopic and kinematic maps of ~40 galaxies simultaneously at z~1 and also at z~2. This is the first time galaxy internal motions at these epochs have been probed in such detail. You will use velocity and dispersion maps to measure the angular momentum of galaxies in the high redshift Universe and also their dark matter content and compare with theoretical models. There will also be opportunities to work with the Keck telescopes in Hawaii for complementary observations and propose for new JWST observations. You will be supervised by Prof. Karl Glazebrook (FAA) an internationally recognised leader in the study of high-redshift galaxies who has been working with JWST since its launch, be a member of the international MSA3D team and colocated with the JWST Australian Data Centre team that will provide extensive support for understanding JWST observations.

Figure: JWST and HST image of a z=1.1 spiral galaxy and kinematic maps extracted by the MSA3D team. (Reference: https://doi.org/10.48550/arXiv.2408.08350)

Supervisor: Prof. Alister Graham

There is a largely-missing population of intermediate-mass black holes (IMBHs) with masses higher than that formed by single stars today (M_bh=1.4 to 120 M_Sun) and less massive than the supermassive black holes (SMBHs: 10⁵—10¹⁰ M_Sun) known to reside at the centres of big galaxies.  Not surprisingly, astronomers around the world are hotly pursuing the much-anticipated discovery of IMBHs.  This thesis will involve several interconnected projects involving telescope and satellite image analysis and statistical techniques.  Improved methods for estimating both IMBH and SMBH masses will be developed and applied, with ties to the upcoming Large Synoptic Survey Telescope expected.  The coexistence of these massive black holes in dense, compact star clusters at the centres of galaxies is also expected to be a source gravitational radiation detectable by the planned eLISA satellite, for which updated predictions will be made.

Students will benefit from membership in the ARC Centre of Excellence for Gravitational Wave Discovery, OzGrav.

Supervisors: Prof. Alister Graham

This project will explore how stars are distributed in galaxy images obtained from both ground-based telescopes and satellites such as Hubble and Spitzer. The structure of galaxies reveals much about how they formed, how they are connected with one another and also with the massive black holes that reside in their cores. This knowledge will be used to pursue a number of exciting topics at the forefront of astronomy. A feeling for the type of research done with Prof. Graham can be seen in his Press Releases.

Image: Artistic impression of a black hole featured on the cover of Swinburne University's 2019 annual report. Credit: James Josephides and Alister Graham.

Supervisors: A.Prof. Glenn Kacprzak and Prof. Michael Murphy

Ever wonder why some galaxies form stars while others do not? Or where does all the fuel for star-formation come from and what regulates it? The evolution of galaxies is intimately tied to their gas cycles - the gas accretion, star formation, stellar death and gas expulsion. As galaxies evolve, their gas cycles (known as feedback), give rise to an extended gaseous halo surrounding galaxies. Understanding how feedback works has become recognized as THE critical unknown process missing to fully understand galaxy evolution. Therefore, gaseous galaxy halos are the key astrophysical laboratories harbouring the detailed physics of how galactic feedback governs galaxy evolution. Observationally, galaxy halos are studied with great sensitivity using quasar absorption lines. Imprinted on the quasar spectrum are the motions, chemical content, density, and temperature of the gas. These absorption signatures provide details that are unobtainable using any other method of observation. Here, the student will join an international collaboration and will examine how the host galaxy properties are linked to their circumgalactic gas properties using Hubble Space Telescope and Keck Telescope data.

Supervisors: Dr. Ben McAllister

The nature of dark matter is one of the biggest mysteries in modern science – it makes up five sixths of the matter in the Universe, and is of unknown composition. It surrounds and passes through the Earth at all times.

Axions are a hypothetical particle, and one of the leading candidates for dark matter. Swinburne is building a new axion detector to try and measure small effects induced by dark matter when it passes through the laboratory, and shed light on the mystery. The kind of experiment we are building is called an axion haloscope.

The detector is currently being constructed and will be hosted at Swinburne. There is work to be done on various aspects of the project, from optimal detector design, to manufacturing and characterisation, to advanced readout technology, to control software and data analysis.

This project could focus on any of these areas, tailored to fit the skills and interests of the candidate. There is room for multiple students, and you will be working in a small team with other researchers. For example, this project could include aspects of mechanical and RF design, material science, computational modelling, software to control the detector and associated equipment, or on a pipeline to acquire and tease through experimental data for hints of new physics.

Supervisors: Prof. Michael Murphy

The fundamental constants characterise the strength of nature's forces. Their constancy has been tested in laboratories to extraordinary precision, and they have been mapped across the universe. But new theories, that go beyond the standard model of particle physics, suggest these "constants" may vary where dark matter is highly concentrated, like the centres of galaxies, including our own. This PhD project will be part of an ongoing effort to map the fine-structure constant – alpha, the strength of electromagnetism – closer to our Milky Way's Centre. To measure alpha, we carefully compare spectra of stars near the Centre, about 23,000 light-years away, with very similar stars in our local region. We are currently observing these stars with the Keck Observatory (Hawai`i), of which Swinburne is a partner, and are proposing to do the same with the Very Large Telescope (Chile). Depending on the interests of the student, there can be observational or theoretical avenues to explore in this PhD project: the student may participate in the astronomical observations, data analysis and measurement of alpha, or they could work on advanced quantum mechanical calculations to determine how the spectra of stars depend on fundamental constants. These and other options will be discussed with the candidate. Further reading: Murphy et al. (2022, Science, 378, 634)

Supervisors: Prof. Michael Murphy

The universe is not only expanding, its expansion is accelerating … we think. The evidence for this earned the 2011 Physics Nobel Prize, but we have never actually observed the universe's expansion rate changing with time. Instead we measure the universe's geometry and, through Einstein's equations, infer its dynamics. But are Einstein's equations correct on the global scale of the universe? We don't know! To test this, we need to observe the cosmological redshifts of distant objects changing in real time. This "redshift drift" experiment would require exceptionally stable spectrographs and ultra-precise spectroscopy of distant, faint quasars. Can this really be done? There are many efforts around the world towards this dream.

This project could take many different directions depending on the candidate's skills and interests. For example, can we label the wavelengths of light received in our spectrographs accurately enough, using new "laser frequency combs"? We've been performing a new experiment performed with the ESPRESSO spectrograph on the Very Large Telescope in Chile to find out. Another example: Can we compare observations of quasars well enough to reveal the tiny effect? We also want to know whether we can process the astronomical images of spectra well enough to see such tiny effects. Whichever direction is followed, this project will be directly funded through the ARC Centre for Excellence in Optical Microcombs for Breakthrough Science, COMBS. The candidate will be connected with the COMBS network, and also with working groups of the European Southern Observatory which is building a spectrograph on the future, 39-meter Extremely Large Telescope which may be capable of the redshift drift experiment. The possible projects would suit a candidate interested in cosmology, ultra-precise spectroscopy, data analysis, and/or astronomical instrumenta

Supervisors: Dr. Jade Powell

Over a hundred gravitational-wave signals have now been detected from the mergers of black holes and neutron stars, but other sources of gravitational waves have not yet been discovered. Some of the most violent explosive events in the Universe are predicted to emit bursts of gravitational waves, and may result in the next big multi-messenger discovery. Potential new sources of gravitational-wave bursts include core-collapse supernovae, cosmic strings, fast radio bursts, magnetars, eccentric compact binary systems and pulsar glitches. Gravitational-wave burst signals often have an unknown waveform shape, and unknown gravitational-wave energy, due to unknown or very complicated progenitor astrophysics. In this project, you will work on the development of searches for gravitational-wave burst signals, and apply these new search techniques to data from the gravitational-wave detectors fifth observing runs.

Supervisors: Dr. Daniel Reardon and Prof. Ryan Shannon

Supermassive black holes - black holes that are billions of times more massive than the Sun, are thought to reside in the Centres of most galaxies. Binary supermassive black holes, produced when galaxies merge, are thought to be the loudest emitters of ultra-low nanohertz-frequency gravitational waves. These gravitational waves can potentially be detected by observing an ensemble of ultra-stable millisecond pulsars (a pulsar timing array) with the most sensitive radio telescopes on Earth. The breakthrough detection is anticipated within the coming years.

In this project, you will develop advanced algorithms to search for, study, and map gravitational wave signal in pulsar timing array data sets. Using the OzStar supercomputer, you will apply these methods to world leading pulsar timing sets, including that from the Swinburne led MeerTime Pulsar Timing Array and the International Pulsar Timing Array. You will interpret the implications of the detections in the context of models of galaxy formation and evolution.

Caption: The 64-dish MeerKAT telescope in South Africa will be extended to form the 196-dish Square Kilometre Array and is used by Swinburne to pioneer signal processing techniques for radio astronomy.

Supervisors: Dr. Sara Webb

The night sky is a dynamic and changing environment, with new and evolving sources known as transients, detected each night. Transients can be identified in large optical surveys due to their changing brightness over time. The most well-known and studied transients are astrophysical in nature, caused by bursts of radiation emitted by exploding or flaring stars and other high energy astrophysical events. However, there is a population of Short Duration Optical Transients (SDOTs), lasting for only seconds to minutes, which are currently poorly understood. These SDOTs are often only detected in single telescope image exposures and are notoriously challenging to follow-up and constrain their origins and properties. Often SDOT events with only single detections are discarded or filtered out in our transient search algorithms for large optical astronomical surveys. It is vital for us to prevent SDOTs being overlooked in upcoming all-sky surveys and uncover their true origins.

The HDR candidate will work with Dr. Sara Webb to uncover the mystery of SDOTs using the largest optical surveys in the world. In 2007 the first millisecond radio transient was discovered and dubbed a Fast Radio Bursts (FRB) (Lorimer et al, 2007). Currently, 1000 (published) FRB events have been detected, with only a fraction of these events observed to repeat (i.e; Spilter et al, 2017, Kumar et al., 2019, Fonseca et al., 2020). The properties of these events have been studied in-depth, aiming to determine the likely origin of the bursts. The Dispersion Measure (DM) of the FRB pulse is used to probe the sources estimated distance (Cordes et al., 2019). It became apparent that the vast majority of FRBs had high DMs suggesting extragalactic origins. Although there exist multiple progenitor theories, no definitive mechanism has been defined (Platts et al., 2019). To fully probe FRBs and their progenitors, a detailed understanding of SDOTs is essential. This is where the Vera C. Rubin Observatory will become curial to understand statistical rates and correlation with FRB rates across the sky, and rejection of artificial events caused by space debris glints.

The HDR candidate will work with data from multiple optical surveys, propose for follow-up telescope time and process data on Swinburne's Supercomputing facilities. In this project you can expect to data mine rich optical datasets for SDOT candidates, produce machine learning algorithms for classification of SDOTs and work alongside expert astronomers across multiple wavelength regimes to investigate these phenomena.