Undergraduate research projects

Students are welcome to choose any project from the four streams below, irrespective of their enrolled stream. Please get in touch with the prospective supervisor, and once agreement has been reached provide the details to the projects coordinator, Alec Duncan, at A.J.Duncan@curtin.edu.au.

Project units

  • Physics Project 1 – Core for all streams, available in both semesters
  • Physics Project 2 – Recommended elective for students with a CWA 65 or greater, available in both semesters
  • The preferred option is to take PP1 in semester 1 and PP2 in semester 2 and combine them into a single year-long project.
  • The choice of project may have a big influence on the direction of your career – so this is an important choice!

Project Assessment

  • End of semester report (40%)
  • Supervisor’s assessment of your performance (40%)
  • Oral presentation (PowerPoint or poster) (10%)
  • Written summaries of seminars you have attended (10%)
  • Fortnightly group meetings with supervisor (0%)

Project Selection Process

By the end of the second week in December:

  • Decide what projects you are interested in and go and talk to potential supervisors.
  • Negotiate the details of the project and get an undertaking from the supervisor that they are prepared to take you on.
  • Email Dr Alec Duncan with the title of your project, and the name of your supervisor
  • Please note that students who delay choosing their project to the Orientation week or later cannot be guaranteed that a desired project or supervisor will be available.

Current projects

Astronomy and Astrophysics

Title: Accretion of planetary debris onto white dwarf stars

Supervisors: Dr Adela Kawka

Suitability: Honours, 3rd year

Description:

Many stars within our Galaxy host planets. Since the majority of stars end their lives as white dwarfs we want to know what happens to these planets once the star evolves and becomes a white dwarf. Up to now no planets have been found around white dwarfs however there is evidence that planets survive but as debris disks.

Elements heavier than helium are expected to sink and disappear below the atmosphere of a white dwarf, leaving either a pure hydrogen or helium atmosphere. However, a significant fraction of white dwarfs shows the presence of heavy elements such as calcium, magnesium and iron which means that they must have been accreted from circumstellar material. The discovery of polluted white dwarfs with large infrared excess suggests that this environment is a debris disk composed of asteroidal/planetary material.

The project will involve extracting, reducing and analysing mid- and high-resolution spectra of white dwarfs from the archives of the European Southern Observatory. These spectra will be fitted with model spectra to determine the white dwarf atmospheric properties such as the effective temperature, surface gravity and abundance of heavy elements. Finally, the measured abundance pattern will be used to determine the likely source of the accreted material.

Title: Advanced calibration and imaging with the MWA

Supervisors: Dr Natasha Hurley-Walker

Suitability: Honours

Description:

The Murchison Widefield Array (MWA) is a low frequency (80 — 300 MHz) radio telescope operating in Western Australia and the only SKA_Low precursor telescope. Its design has many small antennas rather than fewer larger antennas as is typical for radio telescopes working at higher frequencies.

Forming high-fidelity images with the MWA can be challenging. The issues include: the very wide field of view of the MWA, the large data volume due to having many antennas, the corrupting effect of the ionosphere, the unusual reception pattern of the antennas (they are fixed on the ground), among others. Processing MWA data can often violate assumptions inherent in conventional radio astronomy data processing software. More accurate techniques are available but often come at a huge computational cost. Because of this, supercomputers are required to process large quantities of MWA data.

This project aims to investigate and develop novel techniques in radio astronomy data processing to improve the performance and/or fidelity of calibration and imaging algorithms, with a focus on MWA and future SKA_Low data. The application of these techniques has the potential to impact the Epoch of Reionisation (EoR) and GLEAM survey science programs of the MWA, which have each collected several PB of raw data. These techniques will be vital for exploiting the full potential of the new long baselines of the MWA, installed in 2017.

This project is suited to a student with a strong interest in the fundamentals of radio astronomy and a solid background in computer science, maths and/or physics.

Title: A jet seen through a strong stellar wind

Supervisors: Associate Professor James Miller-Jones

Suitability: Honours, 3rd year, summer

Description:

Cygnus X-1 was the first black hole to be convincingly identified.  It consists of a black hole of about 15 solar masses accreting from the stellar wind of a 19 solar-mass companion.  The two stars orbit one another once every 5.6 days.  The black hole launches a relativistic jet that can be directly resolved with the technique of very long baseline interferometry.  As the black hole moves in its orbit, we see the radio emission from the jet through varying amounts of stellar wind.  This wind both absorbs the radio waves from the jet and rotates the plane of polarization through an effect known as Faraday rotation.

In this project, you will use observations from the Karl G. Jansky Very Large Array in the USA to track how the jet spectrum and magnetic field orientation appear to vary as the black hole moves around its orbit.  Since the geometry of the orbit is known, this will allow you to calculate the path length that the radio emission travels through the wind, and hence infer the wind properties.

Title: Automatic reaction to real-time FRB ASKAP triggers with the EDA

Supervisors: Dr Marcin Sokolowski

Suitability: 3rd year, Honours, Masters

Description:

The Engineering Development Array (EDA) is a prototype Square Kilometre Array (SKA) station consisting of 256 bow-tie dipoles (same as used by the Murchison Wide-field Array radio-telescope). It is used for various engineering activities related to the SKA. Since the data acquisition system is capable of recording voltages, it has also been used for low radio-frequency pulsar observations.

The goal of this project is to implement rapid response system for the EDA to react (re-point and record voltages) to external alerts with the main focus on real-time alerts about Fast Radio Bursts (FRBs) detected by the Australian Square Kilometre Array Pathfinder (ASKAP). The dispersion delay between ASKAP and EDA frequencies is longer than 15 seconds for FRBs with dispersion measures DMs above 100 pc/cm^3, which should be sufficient to start recording EDA voltages before arrival of the low-frequency signal. However, a possible extension of the project is to implement a memory voltage buffer to keep the latest 30-60 seconds of data and flush it to the hard drive upon arrival of ASKAP trigger.

Title: Characterising the ionosphere via scintillation measurements with the MWA

Supervisors: Dr John Morgan, Dr Chris Jordan

Suitability: Honours, 3rd year, Summer

Description:

The Murchison Widefield Array (MWA) has proved itself to be an extremely powerful monitor of the ionosphere. Tiny shifts in the location of radio sources can be detected as they are refracted by the ionosphere and this can be used to detect very large-scale features.

There is also a huge untapped source of data on the much smaller-scales in the ionosphere. In this project you will shed a new light on ionospheric structures just a few hundred metres across by monitoring the location, brightness and shape of very bright radio sources as they shift and scintillate on timescales of order 10s.

Title: Detecting and Characterising the most compact objects in the Universe via higher-order moments

Supervisors: Dr John Morgan, Dr Jean-Pierre Macquart

Suitability: Honours, 3rd year, Summer

Description:

Just as stars twinkle in the night sky, radio sources twinkle due to turbulence in the solar wind, a phenomenon known as interplanetary scintillation (IPS). We have developed a revolutionary new way of making IPS observations, detecting many hundreds of sources via their variability (i.e. the standard deviation of a timeseries of brightness measurements). This variability follows an exponential distribution, and we have shown that some of the most compact (and therefore most interesting) IPS sources can also be detected via the skew or kurtosis of the timeseries.

In the project you will use these higher-order moments to detect and characterise the most interesting one or two objects from the many thousands of sources typically detected in an MWA image.

Title: Detecting cosmic rays at the Murchison Widefield Array

(3 projects available)

Supervisors: Dr Clancy James, Professor Steven Tingay

Suitability: Honours, 3rd year, Summer

Description:

Cosmic rays are the highest energy particles in nature – yet we don’t know what produces them. Mostly protons and atomic nuclei, they impact the Earth’s atmosphere, and generate cascades of secondary particles that emit a nanosecond-scale radio pulse. Detecting these short pulses can provide the most detailed estimates of the nature of these particles, and the physical processes of these interactions.

This project will investigate either the theoretical or experimental aspects of detecting these cosmic ray radio pulses with the Murchison Widefield Array. Depending on a student’s preferences/abilities, it could involve:

  • calibrating a prototype particle detector to identify muons at ground level and trigger radio data:
  • testing models of particle interactions at energies unreachable by the Large Hadron Collider, and their effects on the radio emission; or:
  • implementing a computationally efficient synthesis algorithm for turning MWA frequency data back to nanosecond resolution.

All projects are adaptable to students of all levels (3rd year, honours, summer project).

Title: Direct Detection of 21cm Signal from Lyman-alpha Emitters

Supervisors: Associate Professor Cathryn Trott

Suitability: 3rd year, Honours

Description:

The 21cm signal from the Epoch of Reionisation is difficult to detect due to its weakness, contamination from foreground radio galaxies, and complex instrumentation. Added to these challenges is that the actual signal strength and structure is unknown, and so it is difficult to “match” the data to the expected signal. Lyman-alpha emitting galaxies (LAEs) provide an independent tracer of the conditions within the neutral hydrogen gas of the IGM, because the detection of the Lyman-alpha emission line suggests that the region surrounding the galaxy has been ionised. The Suburu telescope has detected LAE galaxies at the end of the EoR. Using 21cm radio data acquired with the MWA, and knowledge of the LAE positions, this project will undertake a matched filter experiment to place limits on the neutral fraction of hydrogen at z=5.7 and z=6.6, and the size of ionised bubbles.

 Title: Do accreting white dwarfs produce jets?

Supervisors: A/Prof James Miller-Jones

Suitability: 3rd year, Summer

Description:

The process of accretion, whereby matter falls onto a central compact object, appears to be associated with jets throughout the Universe, from young stellar objects to neutron stars, stellar-mass black holes and active galactic nuclei.  We therefore expect that accreting white dwarfs should produce jets, but the evidence to date has not definitively proven that this is the case.  In this project, you will analyse radio observations from the e-MERLIN radio telescope in the UK, focussing on an outburst of the best-characterised white dwarf system known as SS Cygni.  This system is known to produce bright and highly variable radio emission during its regular outbursts, which occur every 45 days.  You will use the high resolution of the eMERLIN telescope to try to directly image the jets, as well as producing high time resolution radio light curves to study how the radio brightness changes with time, and how that correlates with the variable optical emission, which tracks the light emitted by the accretion flow. You will also look at the polarisation of the radio emission, in an attempt to determine whether the radio emission is synchrotron radiation from highly relativistic electrons in the jets launched by this fascinating system.

 Title: Fast follow up of Gamma-Ray Bursts with the Murchison Widefield Array

Supervisors: Dr Gemma Anderson, Dr Paul Hancock

Suitability: Honours, 3rd year, Summer

Description:

Gamma-Ray Bursts occur either when a massive star undergoes core collapse or two neutron stars merge. In either case there is a short period in which a huge amount of material is accreted onto a newly formed black hole, and a very powerful jet of gamma-rays is launched  into space. For a small fraction of these events, the jet is aimed toward the Earth where it can be detected by gamma-ray satellites such as Fermi and Swift. These space missions then send immediate alerts to a network on the ground, allowing telescopes such as the Murchison Widefield Array (MWA) to rapidly begin observing the event.

The MWA is a low frequency (80-300 MHz) radio telescope operating in Western Australia and the only operational Square Kilometre Array (SKA)-Low precursor telescope. The MWA is an entirely electronically steered instrument, meaning that it can ‘slew’ to any part of the sky nearly instantaneously. The MWA also has an extremely large field of view. The large field of view and fast slew time means that the MWA is uniquely placed to provide the fastest follow-up radio observations of transient (explosive or outbursting) events, including GRBs.

For the last 3 years, the MWA has been automatically responding to GRBs detected by the Fermi and Swift satellites, obtaining 30 minutes of observations following each outburst. There are now over 700 observations in the database that are being processed, and even more are being taken all the time. An automated pipeline is in place to download and process all these data and make the required images.

In this project you will analyse radio images to look for signs of prompt GRB radio emission – something that has never been seen before at radio frequencies. This project will help build your programing and time management skills, and will allow you to work on the Pawsey supercomputers.

Title: HI absorption in high-redshift radio galaxies

Supervisors: Dr Natasha Hurley-Walker, Dr Nick Seymour

Suitability: Honours

Description:

Before the very first galaxies formed, the Universe was a sea of hydrogen and helium, gently cooling and collapsing. When the first galaxies formed, they ionised the surrounding gas, turning it from an opaque absorbing cloud into the transparent, ionised plasma we see today: this time is called the Epoch of Reionisation.

This change will have occurred at different rates in different locations in the Universe. When we look at high-redshift galaxies which emit in the radio spectrum, any neutral hydrogen along the line-of-sight will absorb the characteristic HI line at that redshift. For the highest-redshift galaxies, this HI line is shifted from 1.4GHz down to ~150MHz. This is within the frequency range of the Murchison Widefield Array, a radio telescope operated by Curtin University and based in the Murchison Radio Observatory.

This project aims to detect HI absorption in high-redshift radio galaxies using the MWA. As this is a spectral line experiment, it requires a unique data processing pipeline and careful control of calibration and systematics. There are several candidate radio galaxies on which first studies could be made, and once a pipeline is developed and detections made, the project can expand to include other high-z candidates currently being identified from the GaLactic and Extragalactic All-sky MWA (GLEAM) survey. There are thousands of hours of data already taken on several fields which would be suitable for this search. This project is designed to synergise with the project “The First Black Holes with MWA”.

Title: How fast can neutron stars eat other stars?

Supervisors: Dr Arash Bahramian

Suitability: Summer

Description:

X-ray binaries are binary systems containing a compact object (neutron star or a black hole) accreting matter from a companion star (typically a star like the Sun). Over time, the strong gravity of the compact object pulls matter from the surface of the donor star and strips its outer layers. Theoretical models predict that as the material falls towards the neutron star/black hole, it loses angular momentum and energy through emission (mostly in X-rays). The stars in the binary get closer as their orbital period shrinks. These predictions have made measurement of orbital period and its changes over time in X-ray binaries a direct method to test our understanding of how black holes and neutron stars devour other stars. Classically, it was thought that any observable change of orbit in X-ray binaries would require observations over centuries/millennia to be detected. However, over the past three decades, changes in orbital period have been observed in in a handful of eclipsing X-ray binaries over timescale of ~years. These findings suggest that there are more complex physical mechanisms (like the star’s magnetic field) significantly impacting evolution of X-ray binaries. Thus a careful study of orbital changes in a larger sample of sample of X-ray binaries is needed to better understand evolution in these systems. In this project, the student will analyze recently obtained X-ray data with the  Swift  satellite of a well-known eclipsing X-ray binary, for which the orbital period waslast measured in the year 2000. This will allow a direct estimate of the rate at which the orbital period has changed in this system and thus constrain the evolution of this system. We anticipate that the X-ray analysis will be included in a refereed publication, with the student as a co-author, pending satisfactory completion of the project.

Title: How variable are black hole jets?

Supervisors: Associate Professor James Miller-Jones

Suitability: 3rd year, summer

Description:

At the beginning and ends of their sporadic outbursts, black holes launch steady, relativistic jets, which are accelerated from the accretion flow close to the black hole.  The accretion flow is significantly variable on all timescales, with root-mean-square fluctuations of order 30-40%.  According to prevailing models, the fluctuations in the accretion flow propagate into the jet, and may be manifested as variable radio emission downstream.  However, the previous generation of radio telescopes did not have the sensitivity to detect this short-timescale variability in the jets (on a timescale of seconds to minutes).  With the upgraded sensitivity of the Karl G. Jansky Very Large Array, you will make a high time resolution light curve of a black hole in its hard X-ray state, for comparison to the simultaneous X-ray fluctuations observed from the accretion flow.  If correlated variability can be detected, we would be able to constrain the jet speed and the geometry of the flow.

Title: Identification of flare stars for radio and optical observations

Supervisors: Dr Paul Hancock, Dr Gemma Anderson

Suitability: 3rd year, Summer

Description:

Variable stars offer a window into the life cycle of stars. Stars of all masses and of all ages exhibit some form of variability: from the seemingly gentle pulsations of Mira and Cepheids, to the blinking of binary stars during transit, to explosive novae that eject material from the surface of a star, end eventually to supernovae that mark the end of a star’s life and their rebirth as a neutron star or black hole. This project will monitor a large number of known variable stars using the Murchison Widefield Array (MWA) and the AstroSmall camera both described below.

The MWA is a low frequency (80-300 MHz) radio telescope operating in Western Australia and the only SKA_Low precursor telescope. The MWA has been in operation for over 5 years and has collected many petabytes of data. The MWA is currently being upgraded to have longer baselines that will increase the spatial resolution and allow for a more detailed study of compact objects such as stars within our Galaxy.

The Desert Fireball Network (DFN) has deployed some 50 DSLR cameras in remote locations around Western and South Australia. These cameras operate autonomously and capture images of the night sky every 15 seconds, with the aim of detecting fireballs and recovering the fallen rocks. One of the DFN cameras has been modified for use as an astronomical sky monitor, searching for flare stars, novae, eclipsing binaries, and as-yet undiscovered bright transient events. This camera, AstroSmall, has been in operation for 2 years and has collected many terabytes of data.

The goal of this project is to generate a list of known variable stars that may have been observed with the MWA and AstroSmall by  drawing from the large amount of existing knowledge present in databases, catalogues, and papers already available on the internet. With time permitting, it will be possible to analyse existing optical and radio data for a subset of these stars.

Title: Identifying optical counterparts of radio sources using citizen science

Supervisors: Dr Natasha Hurley-Walker, Dr Nick Seymour

Suitability: Honours

Description:

The Murchison Widefield Array (MWA) is a low-frequency (80-300 MHz) radio telescope operating in Western Australia and the only SKA_Low precursor telescope. One of the largest science programs for the MWA is the GaLactic and Extragalactic All-sky MWA (GLEAM) survey, which has surveyed the entire visible sky for two years since the MWA commenced operations. GLEAM has collected vast quantities of data. A large part of the first year of this data has been published as an extragalactic source catalogue. These data have relatively low resolution, about 1/30th of a degree; optical data has about 1000x better resolution, so there is some difficulty in identifying exactly which galaxy is emitting radio waves.

TAIPAN is a multi-object spectroscopic galaxy survey starting in late 2017 that will cover the whole southern sky and will obtain spectra for over one million galaxies in the local Universe (z<0.3) over 4 years. This will be the most comprehensive spectroscopic survey of the southern hemisphere ever undertaken. The Taipan galaxy survey will use the refurbished 1.2m UK Schmidt Telescope at Siding Spring Observatory with the new TAIPAN instrument which includes an innovative starbugs optical fibre positioner and a purpose-built spectrograph.

Matching radio sources to optical counterparts is key to understanding the radio population. Optical observations can provide redshifts and reveal crucial properties of the host galaxy, e.g. stellar mass and star formation rate. One useful route is to use higher-resolution, higher-frequency radio catalogues to “bootstrap” from the low-frequency, low-resolution image, up to a better cross-match, but there is still a 100-fold difference in resolution between the optical and the radio. The Radio Galaxy Zoo project (https://radio.galaxyzoo.org/) aims to bridge the gap between infrared and radio observations. We would like to expand this approach to connect the recently-completed GLEAM survey, and the upcoming TAIPAN survey.

The project would involve building on existing cross-matching tools to automate the bootstrap as much as possible, and then working with experienced astronomers to figure out the true matches more difficult cases. Then, these skills need to be transferred to a web-based tutorial in the Radio Galaxy Zoo framework, teaching citizens how to perform the cross-match themselves. Finally, the GLEAM and TAIPAN datasets would be rolled out in the framework, and the project opened to the world to test out.

This project would suit a student interested in outreach and citizen science, with good problem-solving skills. Programming experience would be helpful.

Title: Imaging twinkling radio sources

Supervisors: Dr John Morgan, Dr Rajan Chhetri

Suitability: Summer

Description:

Just as stars twinkle in the night sky, radio sources twinkle due to turbulence in the solar wind, a phenomenon known as interplanetary scintillation (IPS). As well as being useful for predicting space weather events, IPS can also be used to identify and study extremely compact sources.

We have developed a revolutionary new way of making IPS observations, However we have not yet worked out how to optimally deconvolve IPS images. This is a critical step in making a radio image, and will allow us to make more sensitive observations. This project would suit a student who is interested in doing astronomy with future radio telescopes and would really like to dig down into guts of how radio images are made.

Title: Mapping radio Earthshine from the Moon

Supervisors: Dr Ben McKinley

Suitability: Honours, 3rd year

Description:

The Moon acts like a big spherical mirror, reflecting light that originated on Earth back into our telescopes. At optical wavelengths, astronomers have used this ‘Earthshine’ to learn about how the Earth might look to extraterrestrial observers, which in turn aids in our own searches for E.T. Earthshine can also be observed in the radio band, particularly at low frequencies where earth-bound transmitters are constantly broadcasting television and FM/AM radio signals, which leak into space. This project aims to model the reflected radio Earthshine, using ray-tracing techniques to predict what the reflected emission looks like as a function of time as it bounces of the Moon and is observed at the Murchison Widefield Arrray (MWA) telescope in Western Australia. The predictions will then be directly compared to real Moon observations with the MWA. This work is important for astronomers undertaking the Search for Extraterrestrial Intelligence at radio wavelengths, and is also useful for projects aiming to use the Moon as a tool for probing the radio emission from the early Universe.

Title: MWA all-sky monitoring

Supervisors: Dr Marcin Sokolowski

Suitability: 3rd year

Description:

The Murchison Widefield Array (MWA) is a precursor of low-frequency component of the Square Kilometre Array (SKA_Low) located at the Murchison Radio-astronomy Observatory (MRO) in Western Australia. Its wide field of view (FoV) of the order of 25 x 25 deg^2 makes it a very good instrument for wide field transient monitoring. The goal of the project is to look for variable objects in 2-minutes snapshot data collected by the MWA over all pointing directions above 40 deg elevations. The first dataset was recorded in 2018 and the corresponding dataset at the same local sidereal time will be collected in 2019. Subtraction of the corresponding sky images from the two epochs should enable identification of variable sources, which either appeared, disappeared or changed their flux density between the two epochs. 

Title: Neutrino astrophysics with KM3NeT

(2 projects available)

Supervisors: Dr Clancy James, Dr Jean-Pierre Macquart, Dr Ramesh Bhat, Dr Arash Bahramian, Dr Natasha Hurley-Walker

Suitability: Honours, 3rd year, Summer

Description:

KM3NeT is a cubic-kilometre-scale neutrino telescope under construction at the bottom of the Mediterranean. By detecting the bursts of light produced when these almost massless subatomic particles interact, KM3NeT aims to identify where in the universe they come from.  While KM3NeT is still in the construction phase, its precursor facility, ANTARES, has already been operating since 2008.

Honours project

The recent discovery by the IceCube neutrino telescope of neutrinos coming from a blazar – a supermassive black holes with relativistic jets of matter shooting towards us – has raised more questions than it has answered, a key question being – why haven’t we seen neutrinos the other ~thousand known blazars? This project (suitable for Honours level) would involve analysing blazar x-ray from XMM, Chandra, and/or Swift satellites to which blazars could be producing neutrinos, and testing this with KM3NeT’s predecessor, ANTARES.

Summer or 3rd-year project

A further possibility is: could pulsars produce neutrinos? The extremely strong magnetic fields of these rapidly rotating neutron stars are energetically capable of accelerating protons to the energies required for neutrino production.  This project would involve correlating known pulsars with ANTARES data to test this hypothesis.

Title: Probing the Local Hot Bubble using low-frequency pulsar measurements

Supervisors: Dr Ramesh Bhat

Suitability: Honours, 3rd year

Description:

Pulsars make excellent tools to study the interstellar medium (ISM) of our Galaxy. Their radiation is beamed and polarised, and appear to an observer on the Earth as pulsed and dispersed. The compactness of pulsars make them ideal point sources, and as a result their signals are subject to a rich variety of propagation phenomena  as they make their way through the interstellar medium to reach us. These properties make pulsars unique probes of the intervening interstellar plasma, especially its density structure and turbulence at very small scales. The most notable ISM effects are scintillation (i.e. the radio analogue of twinkling) and pulse broadening (lengthening of the pulse profile), both arising from multi-path propagation through the ISM, and are most pronounced at the low frequency bands in which the Murchison Widefield Array (MWA) operates (from ~80 to ~300 MHz).  Pulsars located within a few kilo parsecs of the Sun are of particular interest as their scintillation and dispersion properties will be substantially influenced by the material in and around prominent local features such as the Local Bubble and its nearest neighbour, the Loop I (also known as the North Polar Spur). Observations at X-ray and EUV bands also point to the evidence for an interaction zone between these two bubbles, which can be best studied using nearby pulsars in the southern hemisphere. In this project you will make use of an increasing number of low-frequency pulsar measurements that are emerging from the MWA as well as published measurements from the literature to revisit (and refine) our current model for the Local Interstellar Medium; specifically the distribution of turbulent plasma in and around the Local Bubble and Loop I. Findings from this investigation will be of great interest to both pulsar and ISM researchers, besides yielding a better understanding of our own local interstellar environment. 

Title: Probing the Milky Way’s invisible gas via interstellar scintillation

Supervisors: Dr Paul Hancock, Dr Gemma Anderson

Suitability: Honours, 3rd year, Summer

Description:

The gas between the stars (interstellar medium or ISM) accounts for around 15% of the total mass in the disk of the Milky Way, but with a density that is so low that it is difficult to observe directly. Some of the ISM is either hot or dense enough that we can observe it directly but for the most part, the ISM is invisible. When the ISM becomes ionised, the free electrons can disturb our view of background galaxies by focusing and defocusing the light and causing a scintillation analogous to the twinkling of stars that we can see with the naked eye at night.

The Murchison Widefield Array (MWA) is a low frequency (80-300 MHz) radio telescope operating in Western Australia and the only SKA_Low precursor telescope. We have conducted a survey with the MWA that repeatedly imaged thousands of galaxies. With a carefully calibrated set of images, we can then look for sources that are scintillating, which will in turn allow us to map the turbulence within the interstellar medium. We have developed a theoretical model that will predict the distribution of turbulence, and are now looking to test this model with real data.

This project will involve taking a set of already created images, performing some quality assurance tests, and then creating catalogues of sources, and searching for variability. This project will involve working with python code on linux based systems, including supercomputers and cloud based machines at the Pawsey supercomputing facility.

Title: Properties of radio galaxy hot-spots at low frequencies

Supervisors: Rajan Chhetri, John Morgan

Suitability: 3rd year, Summer

Description:

At low radio frequencies (a few tens to few hundreds of megahertz) the extra-galactic sky is dominated by radio galaxies. Radio galaxies are among the most powerful structures in the Universe that span up to mega parsec scales and are powered by central active galactic nuclei (AGN) that are expected to harbour supermassive black holes. Collimated jets originating from the central AGN transport material outwards and interact with the intergalactic media (IGM), dispersing the material and forming radio galaxies. Hot-spots are formed at places where the jets interact with the IGM and terminate. Low frequency radio properties of hot-spots are not well known since telescopes are challenged by the angular resolution capability required to identify them. Using the newly developed technique of widefield interplanetary scintillation (IPS) with the Murchison Widefield Array (MWA), we are able to identify radio galaxies that harbour arcsecond scale components in them. This provides a unique opportunity to study hot-spots in large number of objects by selecting objects that do not scintillate strongly. You will combine the published IPS catalogue with other radio frequency catalogues to identify radio galaxies with hot-spots and study how they behave at different radio frequencies.

Title: Radio recombination lines with the MWA

Supervisors: Dr Natasha Hurley-Walker

Suitability: Honours

Description:

Radio recombination lines (RRL) are produced when atoms cascade into a series of successively lower ionisation states.  In particular, the RRLs found at low frequencies are highly sensitive probes of the environment where the atoms are found, making them useful diagnostics of temperature, density and pressure.

RRLs at low frequencies were first discovered in 1980 and have since been discovered at frequencies from 14 to 1420MHz.  However, the region between 100 — 200MHz is not well studied.  Early studies suggest that somewhere between 100 and 200MHz the RRLs transition from emission lines to absorption lines. Recent constraints from studies by LOFAR have suggested that this transition may be around 130MHz.

This project will utilize data cubes generated and published by Tremblay et al (MNRAS submitted) as part of a spectral line survey with the Murchison Widefield Array (MWA) to search for RRLs, with a particular focus on carbon recombination lines from 103 to 133MHz.

In 2017 the MWA received upgrades to increase its resolution, so new data taken in this mode may also be used to search for lines, adopting existing spectral line pipelines. This project is suited to a student with a strong grounding in astrophysics and a good understanding or willingness to learn statistics so that these sensitive measurements may be made in a robust and quantitative way.

Title: Searching for Diffuse Radio Emission in Low Mass Systems

Supervisors: Professor Melanie Johnston-Hollitt

Suitability: Honours

Description:

In the hierarchical structure assembly of the universe matter is structured in galaxy groups, clusters and superclusters. It has long been known that galaxy clusters exhibit diffuse radio emission in the form of radio haloes and relics which are vast regions of radio emission associated with turbulence in the intracluster medium or cluster shocks, respectively. However there is an open question as to how massive a cluster must be in order to generate detectable diffuse radio emission, or indeed if galaxy groups, rather than clusters can also produce diffuse emission. Recent evidence suggests that both low mass galaxy clusters (less than 5 x 10^14 solar masses) and galaxy groups do have diffuse radio emission. This project designed to test such claims via use of data from the Murchison Widefield Array (MWA). The MWA is the world’s premier instrument for detecting radio haloes and relics in nearby systems. Using new and archival data you will determine the incidence of diffuse emission in low mass clusters and galaxy groups in the local (0.1 > z) universe. Using these results we will re-examine known radio halo scaling relations, potentially pushing them into the as yet unexplored region of parameter space for low mass systems. Results of this work should be publishable in a referee journal.  

Title: Searching for the First Black Holes with the MWA

Supervisors: Dr Nick Seymour

Suitability: Honours, 3rd year, Summer

Description:

The origin and evolution of super-massive black holes remains a fundamental question in astrophysics. Radio surveys have the capability to detect such sources in the very early Universe. This project will examine techniques to select these rare sources from the large catalogues of radio sources that exist. In particular this project will take advantage of the broad frequency range of the Murchison Widefield Array to help down-select such sources. This project will then select potential sources for follow-up by cross-matching with deep optical and IR surveys.  

Title: Searching for the elusive pulsar in the supernova SN 1987A

Supervisors: Dr Ramesh Bhat

Suitability: 3rd year

Description:

The supernova SN1987A in our Galactic backyard (the Large Magellanic Cloud) has been an object of extensive research over the past decades. As is well known, this supernova produced a neutrino burst at the time of its explosion, signaling the birth of a neutron star. However, despite several intensive searches over the past three decades, a pulsar has not yet been detected, which remains a mystery. Admittedly, the searches so far are unable to preclude the existence of a slowly-spinning pulsar (spin periods > 100 milliseconds) with modest surface magnetic field ($\sim10^{11-12}$ Gauss) and somewhat less energetic compared to most canonical pulsars. Moreover, the search efforts to date have all been carried out at frequencies above 400 MHz. The Murchison Widefield Array (MWA) thus presents a new parameter space to search for this elusive pulsar. Even with its modest sensitivity, a putative pulsar may be detectable, provided its radio spectrum is very steep (e.g. the Crab pulsar) and the pulsed emission is not subject to severe scattering at the low frequencies of the MWA. In this project you will process new observations made with the MWA to form a sensitive tied-array beam pointed toward the centre of this supernova and perform a systematic and thorough search for any likely pulsar candidate signals. The techniques will involve searching for both potential giant pulses (i.e. ultra-bright, short-duration bursts) as well as periodic emission. A positive result would undoubtedly mark a significant discovery and will offer the unique opportunity to study a pulsar at the beginning of its life, and will have several important implications for understanding pulsar birth periods, besides providing valuable insights into the origin and early evolution of pulsars produced by core-collapse supernovae.

Title: Searching for the origin of magnetic fields in white dwarf stars

Supervisors: Dr Adela Kawka

Suitability: Honours, 3rd year

Description:

The majority of stars end their life as a white dwarf. These stellar remnants are burned out cores which are slowly releasing their internal heat. Due to their high gravity, the majority of stars have atmospheres that are hydrogen-rich or helium-rich. White dwarf atmospheres are open to direct investigations and show the effect of a unique range of physical phenomena. One of these is the presence of magnetic fields in a significant fraction of white dwarfs. The presence of a magnetic field is revealed by Zeeman splitted spectral lines. The origin of these magnetic fields remains an open question, although several theories have been proposed. The merger of two stars is the preferred origin based on current observations. One of these is that magnetic fields are observed more frequently in some spectral types compared to others. The European Southern Observatory (ESO) has been obtaining spectra for several decades and has amassed a large archive of data. You will extract spectra from the ESO archive with the aim of searching for magnetic fields and analyse them to determine their atmospheric parameters and measure their magnetic field strength. You will also explore any connection between the incidence and strength of magnetic fields and other white dwarf properties.

Title: Searching for transients and variables in the GaLactic and Extragalactic All-Sky MWA (GLEAM) survey

Supervisors: Dr Paul Hancock, Dr Natasha Hurley-Walker

Suitability: Honours

Description:

The Murchison Widefield Array (MWA) is a low frequency (80-300 MHz) radio telescope operating in Western Australia and the only SKA_Low precursor telescope. One of the largest science programs for the MWA is the GaLactic and Extragalactic All-sky MWA (GLEAM) survey, which has surveyed the entire visible sky for two years since the MWA commenced operations.

GLEAM has collected vast quantities of data. A large part of the first year of this data has been published as an extragalactic source catalogue. However, to produce this catalogue, all of the data was averaged together in time. The original data in full time resolution still remains to be investigated: hidden in these images are possible transient events, such as: flaring M-dwarf stars, reflective space junk, and potentially other undiscovered sources. There are also many astrophysical reasons for sources to change in brightness with time, such as scintillation from intervening plasma, and the flaring and dimming of distant black holes.

The project involves careful re-analysis of the original GLEAM data, using the combined catalogue as a reliable reference source. The student will search for objects which do not appear in the combined catalogue (transients), and identify their nature. There is also the potential to monitor the brightness of sources over time (variables). With approximately 7million source measurements to search and correlate, organisation and clear thinking are crucial skills.

This project would suit a student with good programming skills who is willing to learn more and search a large dataset for potentially interesting events.

Title: Shooting for the Moon – detecting ultra-high-energy cosmic rays with the Five hundred metre Aperture Spherical Telescope (FAST)

Supervisors: Dr Clancy James

Suitability: Honours

Description:

The Lunar Askaryan technique is a method to detect the very rare ultra-high-energy, which impact the Earth at the rate of only once per square kilometer per hundred years. By observing the lunar surface with a powerful radio telescope, the entire visible surface of the Moon (20 million km) can be turned into a cosmic ray detector, allowing these extremely rare particles to be studied.

The only current telescope with the power to detect these cosmic rays is FAST, the Five hundred metre Aperture Spherical Telescope, which is now being commissioned in Guizhou Province, China.  Curtin University is collaborating with the Chinese National Academies of Science and Shanghai University to use FAST to detect these cosmic ray signals.

The pulses are expected to be short and sharp, lasting only a few nanoseconds – or they would be, if the surface of the Moon was smooth. However, it is not, and the effects of lunar surface roughness on these pulses is unknown. This project would involve using simulations of high-energy particle cascades, together with measurements of the Moon’s surface from lunar orbiting satellites, to determine the effects of lunar roughness on the pulse shape. This would allow an optimum detection algorithm to be developed in preparation for future observations with FAST.

Title: Silicon monoxide masers towards evolved stars

Supervisors: Dr Chris Jordan

Suitability: Honours, 3rd year

Description:

Asymptotic giant branch stars and red super-giant stars are common sources to power silicon monoxide (SiO) masers.  Masers can be thought of as radio-wavelength lasers, and are powered by energetic and exotic conditions in space.  In this case, SiO masers are powered by in-falling and out-flowing motions of gas surrounding an evolved star.  As not much more is known about these masers, this project presents an opportunity to advance the “big picture” science of evolved stars.  In this third year or honours project, the student will process and analyse data collected with the Australia Telescope Compact Array, a radio telescope in northern New South Wales, with approximately 60 targets.  Each of the target observations contains multiple spectral line transitions, including each of the v=1, 2 and 3 maser line transitions; any discovery of relationships discovered between the different spectral lines wouldbe an important contribution to the understanding of these masers. In extremely rare cases SiO masers are associated with a star-formation region. Such a discovery would be very important warranting further investigations. In addition,  there is a small chance that these data contain SiO masers associated with a star-formation region, which would be an exceedingly rare detection.  In the course of this work, the student will develop a good understanding of interferometry and data processing.  The results from this work could easily be formatted into a publication, which would be of huge benefit to a student pursuing research into the future with a PhD or masters project. The project is suitable as either a third year or an honours project.

Title: Simulated detection of space junk collisions in Earth orbit using the Murchison Widefield Array

Supervisors: Prof Steven Tingay

Suitability: 3rd year, Honours

Description:

Civilian and Defence applications in space have recently gained a lot of attention in Australia, leading the Commonwealth Government to announce the establishment of a national space agency.

In the Curtin Institute of Radio Astronomy (CIRA), many of the activities we undertake in radio astronomy research (science and engineering) toward the Square Kilometre Array (SKA) can be translated into space industry and Defence applications.

In particular, we are exploring the ability to use next generation radio telescopes, such as the Curtin-led Murchison Widefield Array (MWA: the only operational precursor for the $1B Square Kilometre Array) to track space debris in Earth orbit, using passive radar techniques.

We have multiple PhD students working in this area and a funded project via the Commonwealth Government Defence Innovation Hub.  Tracking and monitoring space debris may become a large strategic focus for the new Australian space agency.

This project will focus on a particular advantage that the MWA has for space debris detection and tracking – its massively wide field of view on the sky.  The MWA can cover up to 1000 sq. deg. of sky, thereby potentially detecting large numbers of individual pieces of space junk in every observation.  Typically, existing space debris monitors can currently only track one piece of debris at a time.

This MWA capability has high relevance to debris breakup events, when two large pieces of debris collide and produce a large number of smaller pieces of debris, with orbits different to their originators.  These events pose a significant risk to active assets in orbit, as the debris cloud represents new pieces of uncharacterized space junk (look up the Kessler syndrome).  An example of a debris breakup event (2009 collision of defunct Russian Cosmos satellite and an active Iridium satellite) can be seen at: https://www.youtube.com/watch?v=JyG3zqLyW8k .

With its wide field of view, the MWA can rapidly respond to breakup events and observe the debris cloud in its entirety, thereby obtaining information on the new debris and allowing a risk assessment for active assets.

In this project, the student will:

  • Explore methods to simulate collisions such as the example above, considering a range of debris masses, breakup mechanisms, and orbits;
  • Examine the characteristics of the debris clouds generated, particularly the range of resultant orbits produced and how they appear from the surface of the Earth;
  • Simulate the observation of the debris cloud using the MWA, considering its wide field of view, sensitivity, and frequency coverage;
  • Produce a paper for publication in a refereed journal. 

Title: Targeted searches for millisecond pulsars with the Murchison Widefield Array

Supervisors: Dr Ramesh Bhat, Dr Arash Bahramian

Suitability: Honours, 3rd year

Description:

The clock-like stability of millisecond pulsars, i.e. those with rotation periods of the order of a few to several milliseconds, makes them especially sought after for high-profile science applications such as searching for ultra-low frequency gravitational waves and probing the state of ultra-dense matter. Recent approaches involving radio follow-up observations of Fermi-LAT pulsars and promising candidates from the  gamma-ray population have been very successful, with the discovery of more than 50 pulsars to date from coordinated searches using multiple facilities around the world. The growing observational evidence for a steeper-than-usual spectrum of such pulsars makes low-frequency searches particularly promising to find more such objects, as vividly demonstrated by the recent  LOFAR discovery of  the fastest spinning millisecond pulsar in the Galactic field. The Murchison Widefield Array (MWA) in Western Australia — a next-generation radio telescope and the official low-frequency precursor for the SKA — has been fully geared up for undertaking high-sensitivity targeted searches for millisecond pulsars. In particular, its newly-developed capability to reconstruct high-time resolution (~microsecond) voltage time series via novel signal processing algorithms allows to retain optimal sensitivity to the detection of short-period pulsars at very low frequencies of the MWA. This project will involve performing extensive searches for  fast-spinning pulsars (including those in binary systems) toward candidate sources that are carefully selected from the Fermi gamma-ray source catalog. Targets of particular interest include sources in the far southern sky that are beyond the reach of northern facilities, or low-luminous objects missed in previous (high-frequency) searches. Besides their applicability for high-precision timing programs such as pulsar timing arrays,  any newly-discovered pulsars will also prove valuable for understanding complex stellar evolutionary scenarios including the recycling process.

Title: “The A-Team”: Low-frequency Observations of the Brightest Radio Galaxies in the Southern Sky

Supervisors: Dr Natasha Hurley-Walker

Suitability: Honours

The Murchison Widefield Array (MWA) is a low frequency (80 — 300 MHz) radio telescope operating in Western Australia; its location in the southern hemisphere gives it an excellent view of the Galactic Plane, and several bright radio galaxies: Hercules A, Fornax A, Virgo A, Hydra A, Centaurus A, and Pictor A: colloquially and collectively called “The A-Team”.

These radio galaxies are some of the closest and brightest objects visible with the telescope, but are so bright that they are often removed or “peeled” from observations without being well-characterised, in order to reveal fainter sources. However, these objects are interesting, because they are powerful, bright, and close enough that even with the MWA, relatively fine details can be observed. At low frequencies, this can give insights into the nature of the jets emitting from the central black hole; for instance, it is suspected that the jets of Pictor A become partially synchrotron self-absorbed, causing the spectrum to flatten at low frequencies.

This project aims to use the best observations from many hundreds of hours of observations of these very bright sources to completely characterise them over the entire MWA band, as well as new high-resolution observations from the extended MWA and the GMRT to explore their complex morphologies at low frequencies. The resulting sky models will be extremely useful for calibration and peeling for the rest of the international MWA team, and also for future work with the Square Kilometre Array. Insights into the astrophysics of the individual sources may well result in papers in refereed journals.

This project is suited to a student with a strong grounding in astrophysics and a willing to learn various software data reduction packages in order to create the best images possible.

Title: The search for flaring and exploding stars using an autonomous camera deployed in the WA desert

Supervisors: Dr Paul Hancock

Suitability: Honours, 3rd year, Summer

Description:

Variable stars offer a window into the life cycle of stars. Stars of all masses and of all ages exhibit some form of variability: from the seemingly gentle pulsations of Mira and Cepheids, to the blinking of binary stars during transit, to explosive novae that eject material from the surface of a star, end eventually to supernovae that mark the end of a star’s life and their rebirth as a neutron star or black hole. To study variability there are two main approaches: a very deep and sensitive survey of a small patch of sky, or a less sensitive but much more inclusive study of a large area of sky. The advantage of a large area, low sensitivity survey is that it doesn’t require an enormous and expensive telescope, just a lot of images from a consumer grade camera.

The Desert Fireball Network (DFN) has deployed some 50 DSLR cameras in remote locations around Western and South Australia. These cameras operate autonomously and capture images of the night sky every 15 seconds, with the aim of detecting fireballs and recovering the fallen rocks. One of the DFN cameras has been modified for use as an astronomical sky monitor, searching for flare stars, novae, eclipsing binaries, and as-yet undiscovered bright transient events. This camera, AstroSmall, has been in operation for 2 years and has collected many terabytes of data.

Over the last year we have developed a calibration method that allows us to measure precise and accurate star positions and magnitudes. This project will require the use of the Pawsey supercomputing facility to calibrate many months worth of images, and make extensive light curves for tens of thousands of stars. The goal is to conduct a blind search for the most variable, and most interesting stars so that we can study them in detail. Some of these transient events will have simultaneous radio observations with the Murchison Widefield Array, which will give us an even better understanding of the events. This project is suited to a student that wants to improve their computing and programing skills, and who wants to learn about the many types of variables stars.

Title: Timing properties of X-ray binaries in star cluster 47 Tuc

Supervisors: Dr Arash Bahramian

Suitability: 3rd year

Description:

47 Tuc is a star cluster containing numerous exotic compact stellar objects like white dwarfs, neutron star or black holes in binary systems with other stars. In these binaries the compact object accretes matter from the companion star in form of an accretion disk. The temperature in the accretion disk can reach millions of degrees, making it emit significantly in the X-rays. X-ray binaries in 47 Tuc are among best study cases among X-ray binaries as their distance is accurately measured and they are not obscured substantially by the interstellar medium. Since the launch of Chandra X-ray observatory, these systems have been studied in details through spectroscopy. However, their timing properties have been left relatively unexplored. In this project, we aim to take advantage of deep continuous Chandra X-ray observations of this cluster to look for signatures of stellar rotation (e.g., rotation of an accreting white dwarf while accreting from another star), orbital modulations (as the companion star passes in front of the compact object and the accretion disk), and possibly precession of the system.

Title: Understanding Fast Radio Bursts

(6 projects available)

Supervisors: Dr Jean-Pierre Macquart, Dr Ramesh Bhat, Dr Clancy James

Suitability: Honours

Description:

Fast Radio Bursts (FRBs) are a newly-discovered population of millisecond-timescale transient events.  Their origin is unknown, but they are thought to emanate at cosmological distances, making the observed emission from these events so luminous that their energetics pose a challenge to models of how radio emission could be produced. Only ~35 of these events have been detected since their discovery in 2007 and the acquisition of a larger sample of events will help us to understand the nature of these events.

The field is currently grappling with the most fundamental questions about these events:

  • What is their spectrum?
  • What is the brightness distribution?
  • Do FRBs represent one-off cataclysmic explosions, or do they repeat?
  • Only one FRB has currently been detected to repeat, despite intense campaigns to detect repetitions at the locations of other FRBs. Is this because repetitions are rare, or because the “repeating FRB” is a qualitatively different type of event to the other FRBs?
  • What are the progenitors of these events?
  • How distant are these events? Their distance distribution can disentangle their evolutionary history, a key component in finding the progenitors of these events.

CIRA is a key member of the CRAFT survey on the Australian SKA Pathfinder (ASKAP), which is currently detecting Fast Radio Bursts at a high rate, and which will soon be able to localise the bursts to 1” on the sky.

We are offering several projects in this field:

  1. Searching for repeating FRBs in ASKAP data
    Unlike previous FRB surveys, ASKAP constantly monitors the same patches of sky for FRBs.  Hence, the region of sky in which any FRB is detected will have been observed many times.  Here you will search the ASKAP data at the locations and dispersion measures of known FRBs to look for faint bursts by examining the statistical properties of the noise.
  2. Searching for repeating FRBs with the Green Bank Telescope
    The Green Bank telescope is currently the world’s largest fully-steerable radio telescope.  Here you will examine sensitive observations at the locations of known FRB events to look for exceedingly faint repeat bursts.
  3. Parkes repetition data
    Here you will use data from the 64-m Parkes radiotelescope to search for repeat bursts from known FRBs.
    The detection of a repeating FRB from projects 1, 2 & 3 would enable us to use radio interferometers such as ATCA and the Very Large Array to localise the bursts to sub-arcsecond accuracy and hence determine exactly which galaxies the bursts come from.
  4. Characterising the low-frequency spectrum of FRB emission
    No FRB has been detected below a frequency of ~600 MHz.  Is this because no radiation is produced at low frequencies, or it is absorbed or scattered?  Or has no-one simply detected it yet?  Here you will examine time-domain data from the Murchison Widefield Array (MWA). A particular advantage of the MWA is that it has been undertaking “shadowing observations” of ASKAP, so that we know the times, locations and dispersion measures of events that should appear in the MWA data.
  5. What are the environments of FRBs?
    ASKAP has now begun localising FRBs to sub-arcsecond precision.  Do they reside in the centres or outskirts of galaxies, and how do their properties relate to their immediate environment?
  6. Interpreting FRB dispersion measures
    The dispersion measures (DMs) of FRBs represent a means to probe the ionized Inter-Galactic Medium, the repository of over half of the Universe’s baryonic (normal) matter.  But how do we interpret the DM?  In this project you will investigate how the DM distribution depends on variations in the distribution of matter along individual sight-lights through the IGM.

Title: Using the MWA to Detect and Monitor Near-Earth Objects

Supervisors: Dr Nick Seymour

Suitability: Honours, 3rd year

Description:

Near-Earth Objects (NEOs) represent an existential threat to life here on Earth. There are long standing programmes with optical and infrared telescopes to discover and monitor NEOs. The Murchison Widefield Array has demonstrated the capability to detect objects such as the Moon and the International Space Station via reflected FM emission from the Earth. This project will involve determining the feasibility of extending this technique to NEOs. This project will involve determining past and future observations of NEOs with the MWA, developing techniques to enhance signals from such sources and applying them to observations of a known NEO previously observed with the MWA in Oct 2017.

Title: Verification of historic Gamma-Ray Bursts in the MWA data

Supervisors: Dr Marcin Sokolowski

Suitability: 3rd year, Honours, Masters

Description:

The Murchison Widefield Array (MWA) is a precursor of the low-frequency component of the Square Kilometre Array (SKA_Low) located at the Murchison Radio-astronomy Observatory (MRO) in the Midwest of Western Australia.

It operates at low radio-frequency range (~80 – 300 MHz) and over the last 5 years it has collected over 20 Petabytes of data. During this time a large number of astrophysical events have been detected and reported in literature, such as for example Gamma-Ray Bursts (GRBs), which are the main focus of this project. Some of these events serendipitously occured in the large field-of-view (FoV) of the MWA. However, many of them were not verified in the MWA images.

Therefore, the aim of this project is to select several interesting events amongst historic GRBs and potentially some supernovae (SNe), which could have low frequency counterparts, process the MWA data and verify presence or absence of the source in the sky images at the expected position. The main focus of the project will be localised GRBs reported by the GCN network (https://gcn.gsfc.nasa.gov/), which were observed by the MWA before, during and after a GRB explosion. However, low radio-frequency afterglows of GRBs are speculated to occur even a few years after the explosion, therefore all MWA observations covering the GRB position and collected after the GRB will be verified in order to derive long-time upper limits for at least several of these events.

Applied Physics

Prof. David Antoine, Remote Sensing and Satellite Research Group (RSSRG)

Prof David Antoine specializes in the use of satellites and in situ optical data to understand oceanic processes and their links to climate and environmental changes. This work is largely based on data from NASA and ESA satellites, and our findings feedback into processing algorithms for these missions.

A number of Earth observation satellites orbit around our Planet, carrying “radiometers”. These instruments record the spectral radiance at the top of the atmosphere, which, after appropriate corrections, provides the spectral reflectance of the upper ocean layer. From the spectral changes of this reflectance, one can derive a number of key environmental quantities, such as the chlorophyll content of phytoplankton (the primary producers of the sea, underlying essentially all oceanic food webs), the sediment load (e.g., as produced by dredging operations), or the absorption by coloured dissolved organic matters (those substances that make the Swan river look like tea).

Key to using satellite observations is having in situ data for validating them. Prof. Antoine has obtained a unique time series of optical data in the Mediterranean Sea through the deployment of a large bio-optical Mooring. (BOUSSOLE: http://www.obs-vlfr.fr/Boussole/), and has also time series of similar measurements off Rottnest island, Perth.

Two examples of possible subjects are provided below but, if you have any other idea that you think might involve satellite remote sensing, please feel free to come and discuss it. We can design a project to suit your interests.

Validation of satellite observations off Rottnest Island, Perth

The RSSRG has ARC funding to deploy a profiling mooring off Rottnest Island, Perth. This new equipment will collect vertical profiles several times a day of optical and biological properties of waters at that site. The data set will allow deriving the water reflectance, which can then be compared to the same parameter as delivered by satellite remote sensing instruments, in particular the “Ocean and Land Colour Imager” (OLCI) launched in 2016 by the European Space Agency (ESA) on board the Sentinel-3 satellite. The work will consist of processing the profiling mooring data set, sourcing the corresponding data from the satellite observations, and evaluating how well they match. The results will be communicated to the “Sentinel validation team”, which is an international group of scientists working on the global evaluation of the quality of OLCI products, under ESA leadership.

Scales of variations of phytoplankton off WA

Physical and biological properties of oceanic waters off Western Australia (WA) are largely influenced by the Leeuwin Current (LC), which is the major southward flow of warm, low-salinity tropical waters along WA coasts. It varies on inter-annual to decadal time scales, in particular under influence of the El Niño Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO). Mesoscale eddies in the Leeuwin Current have profound influence on temperature and chlorophyll distributions in the region. For example, the warm-core eddies that spin off from the LC have a significant effect on the level of productivity in the mid-west region. Here we propose to study the spatial and temporal scales of variation of phytoplankton and primary productivity off WA through the use of NASA and ESA satellite ocean colour remote sensing products and a model of phytoplankton photosynthesis. Archives of such products date back to 1998 and, therefore, allow studying seasonal, inter-annual and decadal changes.

Dr Alec Duncan

Underwater acoustics

I carry out research in the Centre for Marine Science and Technology (CMST). My main area of interest is underwater acoustics, although I also dabble in underwater vehicles, oceanography, musical acoustics, and signal processing in general.

Acoustic particle velocity sensors

Underwater sound measurements are usually carried out using hydrophones that measure sound pressure, however fish and some other marine animals sense the motion of water particles caused by the sound waves instead.  Sensing particle velocity is more difficult than sensing pressure but has the advantage of indicating the direction the sound wave is travelling in, and for environmental applications provides a direct measure of what animals with this type of hearing are sensing.  The aim of this project is to develop and characterise an accelerometer based particle velocity sensor suitable for use in a laboratory tank.

Modelling mechanical stresses in animals exposed to very loud underwater sounds (with Assoc. Prof. Rob McCauley)

The aim of this project is to model the internal mechanical stresses in marine species such as zooplankton, shellfish and fish that result when these animals are subject to the very loud sounds produced by the airgun arrays that are used for offshore seismic exploration.  This would involve the application of analytical and numerical techniques of increasing sophistication, and has direct application to current concerns about the environmental impacts of these surveys.

Using propeller noise as a sound source for subbottom profiling

Boat propellers generate high levels of underwater noise over a wide frequency range. It should be possible to use this noise as a sound source for a simple sonar that would provide information about the layering of sediments in the top few metres of the seabed. A preliminary experiment, carried out in 2009, showed some promise, and it would be good to develop this idea further.

Physics of sound production in whales (with Prof. Sasha Gavrilov)

Great baleen whales produce intense, low-frequency sounds of quite long duration while travelling underwater. It has been observed over the last couples of decades that the frequency of sounds produced by some whale species, e.g. blue whales, has been gradually decreasing over the years.  A number of hypotheses have been suggested to explain this phenomenon. However, none of these suggests a meaningful mechanism of such change in whale vocalization associated with likely causes. The aim of this project would be to come up with an explanation of frequency change in whales calls based on the physics of sound production in great whales.

Dr Christine Erbe

Ship noise in Australian marine habitats

The marine soundscape can be split into its biophony (the sounds of whales, dolphins, fish, crustaceans etc.), geophony (the sounds of wind, rain, waves, ice etc.) and anthrophony (the sounds of human/industrial operations). Ship traffic is the most persistent source of man-made noise in the marine environment—with potentially significant bioacoustic impacts on marine fauna, most of which rely heavily on acoustics for their critical life functions. CMST has recorded the marine soundscape around Australia for 15 years at various sites. Using publicly available position logs of large vessels, we can 1) compute received levels of individual ships, 2) calculate source levels of individual ships by sound propagation modelling, and 3) determine the contribution of shipping to the local noise budgets. This project will suit a mathematically skilled student with some experience in scientific software development, data analysis and numerical modelling. An acoustic background is NOT necessary.

Black Cockatoos Calling

We are looking for two Honours students interested in studying cockatoo acoustics for a year. Black cockatoos, Calyptorhynchus sp., are endangered and specially protected in Western Australia. There is a regular citizen science survey, called the Great Cocky Count, which has provided crucial information on black cockatoo populations.

Cockatoos are noisy. They produce sounds that differ by species, age, gender and behaviour. We want to explore whether passive acoustic listening can provide additional data on population size, distribution and demographics. We have preliminary recordings of Carnaby’s cockatoos near the Curtin University Bentley campus, and of red-tailed black cockatoos in John Forrest National Park. The Honours students will be involved in additional field work, including recordings and visual observations, establish a call repertoire of these two species, correlate calls with behaviour and demographic parameters, and potentially look at changes in calling behaviour as a function of human disturbance.

The bioacoustic repertoire of Australian striped dolphins (Stenella coeruleoalba)

Striped dolphins (Stenella coeruleoalba) are an offshore, pelagic species of dolphin, which are most commonly seen along the edge of the continental shelf or over deep-water canyons. We have little information about the Australian population. Threats are direct catches, fisheries bycatch and pollution. Curtin University’s Centre for Marine Science & Technology has photographic and passive acoustic data for this species, and we are looking for a 1-year Honour’s student to study the bioacoustics of Australian striped dolphins, with the overall aim of characterising their sound repertoire to aid long-term passive acoustic monitoring. We are hoping to fill this position as soon as possible, January 2017 the latest. Depending on timing, there might be opportunities for additional field work.

Variability in acoustic tag performance and detection range

Acoustic tags are increasingly used to track behavioural patterns of numerous marine species, but the long-term performance of the pinging tags and stationary receivers is rarely tested. Biofouling of the receivers, for example, holds potential to significantly reduce performance, affecting the results of marine studies. This project aims to assess directionality, source levels and detection ranges of some acoustic tags in a practical environment and the propagation of their signals. A number of acoustic tag receivers are located at the Mullaloo Beach Lab site. Working in collaboration with Mullaloo Beach Surf LifeSavers tags are to be periodically located in and around the array while tag source levels are also tested. Matlab programming skills will be developed. Kayaking experience preferred.

Dr Iain Parnum

Acoustic remote sensing of the marine environment

I carry out research in the Centre for Marine Science and Technology. My main area of interest is underwater acoustics, particularly acoustic remote sensing of the marine environment.

Projects

  • Measuring and modelling of seafloor backscatter
  • Detection of marine gas seeps using acoustic techniques
  • Underwater acoustic monitoring of marine fauna

 Dr Andrew Woods

Stereoscopic imaging

Stereoscopic 3D Displays are increasingly being used in a wide range of application areas including scientific visualisation, industrial automation, medical imaging as well as gaming and home entertainment.  The Centre for Marine Science and Technology (CMST) has been conducting research into stereoscopic imaging topics for the past 20+ years. Over the past few years several third year physics students have worked on projects related to 3D displays and have revealed some very interesting results. Projects in this area would interest students with an interest in optics, displays, visualisation, and/or data analysis.

Improving the Spectral Quality of Inks for Low Crosstalk Printed 3D Images

A recent journal paper has identified that spectrally impure inks are a major source of crosstalk in printed anaglyph 3D images. The purpose of this project would be to perform optical measurements on a range of new ink types to find inks which offer better spectral performance for 3D purposes. The project will also involve some sleuthing to investigate whether some new technologies, such as quantum dots, might offer some opportunities for better ink spectral quality. A Matlab program is available which can be used to simulate the 3D performance of different inks types. The project may also offer the opportunity for the student to learn about colour management in printers as another way of improving 3D print quality. The mentioned journal paper found that there is considerable opportunity to improve 3D print quality we just need to test the proposed methods. There is prospect for a conference or journal paper to come out of this work.

Ashley Barker (Petritek)

Petritek is looking for students for the following industry based projects (contact Alec Duncan in the first instance).

Project #1

Improvement of embedded software algorithms running onboard a microcontroller to improve spectrums being received. This is an optimization task, it will not actually require embedded C knowledge (but of course if the student wanted to actually code it themselves and learn C, that would be amazing). Once better spectrums can be achieved we would like to make some of these boards to measure around the surface of a volume. Then using the measurements from around the surface and the spectrum data it should be possible to do some maths to interpolate what the composition of the volume looked like and map out regions within the volume.

Project #2

We would like to look at performing a type of survey from drones. At the moment it is done by large aircraft, we would like to use drones to improve safety and quality of measurements. We will be using a different technique for mathematical processing of the data which will require building a mathematical model in matlab and if it can be proved then we would go and make the drone system hopefully as part of the project.

Project #3

This could potentially be done in cooperation with a large oil and gas operator. They have a particular asset that needs scanning with one of our products but it is not quite suited. So we would want to go through and mathematically model all of the different ways that the problem can be conquered. Again this would look like a matlab model.

Project #4

We have designed a new type of sensor for performing much more accurate measurements in industry. At the moment it outputs arbitrary units. We would like a student to come and work with us to fully characterize how those arbitrary units can be translated into useful data under different scenarios. We can manufacture all of the test rigs etc. as necessary.

Materials Physics

Dr William Rickard

Focussed Ion Beam – Scanning Electron Microscope (FIB-SEM) Project

A FIB-SEM combines nanometre resolution imaging with precision patterning of a focussed ion beam enabling the instrument to manipulate a sample at very fine length scales. The Tescan Lyra FIB-SEM, located within the John de Later Centre at Curtin University, is a state-of-the-art instrument that is used for advanced microanalysis in 2D and 3D as well as high precision site-selective sample preparation.

Surface analyses (electron and ion imaging, chemical mapping (EDS), crystallographic mapping (EBSD)), sub-surface analyses (3D imaging, 3D EDS, 3D EBSD) and unique in-situ ToF-SIMS analyses are able to be correlated with site specific atom probe tomography or TEM results which enables a thorough characterisation of highly complex materials on a wide range of length scales.

In this project the student will get trained to operate the FIB-SEM and will run a series of experiments in order to optimise the data collection and data analysis methods for 3D imaging and 3D microanalysis. Other projects involving the ToF-SIMS will also be available.

Dr David Saxey

Atom Probe Tomography

Atom Probe Tomography works by dis-assembling materials one atom at a time, and using software to reconstruct their original 3D locations and chemical identities. It is a powerful tool for the characterisation of materials – unique in its ability to provide three-dimensional chemical information on the atomic scale. Although the technique has existed for some time, the past ten years have seen a rapid uptake, with over 100 machines now installed in laboratories around the world. The range of materials studied has also grown; from metal alloys, to semiconductor device structures, ceramics, and more recently geological materials.

The Geoscience Atom Probe facility, housed within the John de Laeter Centre, operates the first atom probe microscope to be dedicated to geo materials. As such, there are many new and interesting applications within this field, and many opportunities for original research into outstanding scientific problems. In addition to these applications, the physics of the technique itself is also an active area of research, with open questions surrounding the evaporation and ionisation of atoms from the sample under extremely high electric fields. There are also interesting problems in the analysis of the 3D chemical datasets, which can range in size beyond 10^8 atoms.

We are providing a number of opportunities for interested students to contribute to projects within the Geoscience Atom Probe facility, which would include the acquisition of atom probe data, as well as analysis and interpretation of the datasets. There are also opportunities to develop techniques and analysis tools to provide new methods of extracting information from the 3D data.

Prof Charlie Ironside

FIB for Fab

Micro and nano fabrication is a key enabling technique for many aspects of electronics, photonics and biotechnology. Much of modern technology relies on micro and nanofabrication including the CMOS devices used in mobile phones and laptops. Plus nanofabrication is now extensively employed to explore new nanostructures that reveal the quantum nature of the physics underlying many novel devices. In this project we will explore the use of focussed ion beams (FIB) for creating novel nanostructures. The FIB tool can be used mill features less than 100 nm on a variety of materials making it a very versatile tool for quick prototyping of new nanofabricated devices and structures. We will use FIB to make structures with features less than 1 micron on 2 dimensional semiconductors such as grapheme and Gallium Selenide (GaSe) and on optical fibres.

Dr Mark Aylmore and Kelly Merigot

TIMA Project

With the addition of our newest Field Emission Scanning Electron Microscope (FESEM), which is a Tescan Integrated Mineral Analyser (TIMA) fitted with four Energy Dispersive x-ray Spectroscopy (EDS) detectors. The TIMA is specialised towards high throughout mineral liberation analysis. Recent developments in EDS detectors and software have made fast chemical mapping possible. The TIMA uses x-rays to identify the elements that make up the sample being analysed and then compares the collected spectra to a phase database to produce a mineral distribution map. The composition can be determined quickly, though careful consideration must be made as to the sample preparation.

The parameters for EDS mapping have yet to be thoroughly investigated and verified. The project is designed to test the quality of results collected under various conditions and how the collection conditions control the outputs such as minimum grain size analysed. This project would involve an initial period of training to operate the microscope, followed by data collection and comparison of the results. The practical application of this project will be an improved methodology for mineral liberation analysis for all future users of this instrumentation.

Dr Irene Suarez-Martinez, A/Prof Nigel Marks

Structural models for activated carbons

Activated carbons are man-made nanoporous materials synthesized from virtually any carbonaceous precursor such as wood, coal or sugars. They are routinely used as absorbers in gas masks, tobacco filters and water purifiers and are often known as carbon molecular sieves. Despite their numerous applications in industry, very little is known about their structure and the few atomic-scale models available in the literature are rather poor. The broad goal of this project is the development of a computer-based nanoscale model for non-graphitizing carbons which can be used for analysis and prediction of absorbent properties of activated carbons. A variety of specific projects to achieve this objective are available, including molecular dynamics annealing simulations to understand graphitisation, quantum mechanical calculations of oxygen adsorption to assess reactivity during activation, and grand canonical monte carlo simulations of adsorption isotherms used to quantify porosity.

A/Prof Nigel Marks

Atomic polishing of diamond with argon clusters

Atomically flat surfaces are fundamentally important in surface science and for the fabrication of electronic devices. Large, perfectly flat terraces are easily achieved for silicon by rapid thermal annealing or ‘flashing’, but this approach fails for diamond since heating creates graphitic domains. Motivated by the new X-ray Photoelectron Spectroscopy (XPS) facility in Physics, this project will use computer simulation to explore the feasibility of smoothing the diamond surface using an argon cluster beam. The simulations will explore determine whether controlled Ar clusters can remove single atoms, carbon dimers and step edges by exploring the parameter space of cluster size, kinetic energy and incident angle. Experiments on real diamond samples would follow should the simulations suggest the process is viable, using the argon cluster beam on the XPS system in conjunction with XPS and atomic force microscopy.

Dr Irene Suarez-Martinez, A/Prof Nigel Marks

Junctions between Graphene and Nanotubes

Over the last 15 years a plethora of carbon nanostrutures have been developed using graphene and nanotubes as building blocks. One of the landmark concepts is a car-park-style structure in which widely-spaced graphene sheets are linked by carbon nanotubes arranged at right-angles. Recent experiments have shown that nanotubes and graphene can connect at other angles, as long as they are multiples of 30 degrees, and computer models have been developed here at Curtin to illustrate the process. The goal of this project is to explore these junctions in atomistic detail, in particular the nature of the non-hexagonal bonding at the “elbow point” of the junction. The project would primarily use molecular dynamics methods to explore the energetics of the junction, supported by quantum mechanical calculations if necessary.

A/Prof Nigel Marks

Radiation Damage in Graphite & Diamond

High energy particles incident onto a solid typically create a collision cascade in which a large number of atoms are displaced from their lattice sites. Understanding such processes is central to many situations, including nuclear reactors, ion accelerators and particle detectors. Recent work here at Curtin has shown that both graphite and diamond behave in a rather unusual manner. Instead of displaying a liquid-like region, as in most metals and oxide, the collision cascade contains isolated defects distributed along fractal-like trajectories. Many explanations for this behaviour have been proposed, including the low mass of carbon, the crystal structure itself, the density, and the thermal conductivity. To identify which explanation is responsible, molecular dynamics simulations will be performed on a variety of structures and systems; some of the simulations will directly mimic the laboratory, while others will be virtual experiments that have no physical counterpart, such as increasing the mass of carbon atoms.

Dr Carla de Tomas, Dr Irene Suarez-Martinez, A/Prof Nigel Marks

Interatomic Potentials for Carbon

The heart of a successful molecular dynamics simulation is the selection of an appropriate interatomic potential for the calculation of forces and energies. Carbon has proved one of the most difficult elements to describe due its flexible bonding and long-range interactions. More than 40 different potentials have been proposed for carbon, and yet there is no single resource available to compare their performance. This project will use high-performance computers at the Pawsey Centre to perform benchmarking on large carbon systems, specifically regarding amorphization and graphitisation. The data will contribute to an established project using a combination of traditional journal articles and an online comparison tool to enable researchers from around the world to evaluate carbon potentials. Students with particular high levels of skills in computer simulation can consider a whole new data slice, such as calculation of elastic constants or simple carbon nanostructures.

Dr Irene Suarez-Martinez, Dr Matthew Rowles, A/Prof Nigel Marks

Modelling the structure of graphitic and non-graphitic carbon

Various organic materials, when heated to ~3000 °C, transform into either graphitic carbon or non-graphitic carbon. The reasons for this distinction are not fully known, although it is believed that the atomistic and microstructure of the materials play a key role. There is a large body of work on the analysis of these carbons’ structure through the use of X-ray diffraction, with various different models developed over the past 85 years. This project will simulate carbon structures and calculate X-ray diffraction patterns. This simulated data will then be analysed with existing models to extract structural parameters of interest. As these parameters are already known, this will serve as a benchmarking exercise for carbon structural models, which can then be applied to experimental data.

Dr Matthew Rowles

Materials by X-ray diffraction

X-ray diffraction provides a direct probe of the atomic structure of materials. It can be used to provide information on bond distances, crystallite size, thermal expansion, and amounts of phase in a mixture, amongst other parameters of interest. In carrying out these measurements, there are various experimental, specimen, and modelling effects that can affect the accuracy and precision of the derived values. The projects offered in this area investigate data collection and analysis techniques and how they can be optimise to give the best answers. Good programming skills are required for some of the projects.

There are several projects within this application area:

  • Effect of step size, counting time, and angular range on quantitative phase analysis accuracy and precision
  • Absolute quantification of in situ X-ray diffraction of high thermal expansion materials
  • Effect of variable counting time and step width on structure refinement from powder data with large detectors
  • Automatic background removal and phase change identification in in situ X-ray diffraction data

Prof. Craig Buckley, Dr Terry Humphries, Dr Mark Paskevicius, Dr Drew Sheppard, Dr Veronica Sofianos, Dr Matthew Rowles

Thermal Energy Storage Materials for Technological Application

The Hydrogen Storage Research Group (HSRG) specialises in the study of materials for thermal energy storage applications. Past studies have focused on employing the thermodynamics of reversible absorption and desorption of hydrogen from metal hydride compounds (e.g. MgH2 and NaMgH3) to store energy at temperatures of above 300 °C. This thermal energy may be produced by employing concentrating solar power (CSP) to heat the material, a process that is already used to produce electricity in many sites around the world, for example the Crescent Dunes Facility in Nevada, USA. The thermal energy storage systems are used to store the excess heat collected during the day to produce electricity at times of low solar exposure. To improve the efficiency of thermal energy storage systems, that is to produce electricity for longer periods of time, materials that can operate at elevated temperatures are required to be developed. This includes identifying possible compounds, synthesizing and characterising their physical properties.

A number of projects are available in the HSRG to develop novel metal hydrides and metal carbonates that can be used as thermal energy storage materials. Projects would include the synthesis and characterization of novel metal hydrides and metal carbonates for potential incorporation into large scale industrial plants. Thermodynamic determination of the enthalpy and entropy of gas desorption by physical measurements and theoretical calculations must be undertaken to identify technological application, while crystallographic characterization by powder X-ray diffraction will be used to study these materials. A variety of projects are available and can be tailored to suit individual studies. This project is likely to lead to a publication in an international peer reviewed journal.

Prof. Craig Buckley, Dr Terry Humphries, Dr Mark Paskevicius, Dr Drew Sheppard, Dr Veronica Sofianos, Dr Matthew Rowles

Development of Phase Change Materials for thermal storage applications

The Hydrogen Storage Research Group (HSRG) specialises in the study of materials for thermal energy storage applications. There are generally three methods to store heat: 1) Latent heat storage (phase change materials); 2) sensible heat storage (heat capacity of the material); 3) Chemical storage (breaking and forming chemical bonds). Recently, there is an increased focus on developing phase change materials as the technological and engineering requirements are reduced compared to Chemical heat storage materials. A variety of materials with melting points in the temperature region required, e.g >600 °C for Concentrating Solar Power thermal storage applications, can be employed including pure compounds or eutectic mixtures of compounds.

A project is available to develop novel materials to be used as phase change materials for thermal storage applications. This would include identification of possible phase change materials, synthesizing possible candidates and characterizing their thermal energy storage properties. This project is likely to lead to a publication in an international peer reviewed journal.

Dr Mark Paskevicius, Prof. Craig Buckley

Next Generation Battery Materials

New battery technologies offer the possibility for greatly enhanced energy storage capacities. High energy density is critical for most technological applications, such as for portable electronics and vehicles, i.e. more energy in a form that weighs less and takes up less space. Further breakthroughs are required to bring new batteries to reality, especially with regard to the electrolytes. Here, solid-state electrolytes could allow electrochemical reactions to proceed where liquid electrolytes fail, also providing higher electrochemical stabilities and enhanced safety.

Our group has synthesised new types of solid-state electrolytes that have interesting dynamics within the crystal structure. The anions within the structure rapidly reorientate up to 1E10 times per second, promoting the migration of cations, such as Li+, within the structure. These types of solid-state ion conductors have ion conductivities on par with liquids! The challenge is improving the ion conductivity at room temperature for battery applications.

This project will focus on the measurement, characterisation and analysis of electrochemical measurements on new solid-state ion conductors. The materials are air-sensitive and will be handled within an argon-filled glovebox. Measurements will be undertaken using newly acquired equipment by using electrochemical impedance spectroscopy. This data can be collected as a function of temperature by heating the air-tight electrical cell to multiple temperatures. Further analysis will be undertaken to test the voltage-stability and chemical compatibility of the solid-state electrolytes with typical anion and cation materials. It is expected that high-impact peer reviewed publications will result from this project.

Prof. Ricardo Mancera

The beta amyloid-amylin interaction: is there a molecular link between diabetes and Alzheimer’s disease? Biophysical and molecular simulation studies

Type-2 diabetes (T2D) is associated with an increased risk of dementia, including Alzheimer’s disease (AD). The molecular mechanisms behind this association are, however, not well understood. Both of these age-related, chronic diseases feature the accumulation of amyloid protein aggregates (beta amyloid or Aβ in the brain in AD and amylin in the pancreas in T2D). Recent studies at Curtin suggest that Aβ and amylin can co-exist in AD brain and synergistically interact to potentiate cell death and amyloid deposition. These findings suggest that amylin may cross-aggregate with Aβ, forming stable molecular complexes with increased toxicity. The direct interaction of these amyloid proteins is poorly understood, but could play a major role in the genesis and progression of pathological conditions in the brain and pancreas.
This project will offer the opportunity to use either biophysical or molecular dynamics simulation methods to study the interactions of Aβ and amylin and the structure of Aβ-amylin complexes. Surface plasmon resonance (SPR) and isothermal titration calorimetry (ITC) determinations will be used to obtain direct measurements of the kinetics and affinity of binding between Aβ and amylin, as well as of their interactions as pre-formed oligomers with model cell membranes. Molecular dynamics simulations will be used to investigate the structure of the oligomers formed between Aβ and amylin in phospholipid bilayers as well as the changes induced in the structure and stability of these membranes. The outcomes of the project will shed much needed light into the cross-seeding mechanisms that underlie the pathological roles of these proteins in AD and T2D, which could be targeted with anti-aggregation drug molecules.

Designing reconstituted high density lipoproteins as a cholesterol-lowering therapy in cardiovascular disease: a molecular dynamics simulation study

Low levels of cardioprotective high density lipoproteins (HDLs) are associated with cardiovascular disease. Reconstituted HDL (rHDL) therapy can improve atherosclerosis, and can also improve insulin levels in type-2 diabetes and possesses potent anti-inflammatory properties for the treatment of rheumatoid arthritis. Formulations of rHDL mimic the precursors of native HDL, which is the main HDL subclass that mediates the transport of so-called ‘good cholesterol’. Typical formulations involve phospholipid disks with apolipoprotein A-I (ApoA-I). Changes to the lipid composition of the formulation result in different-shaped rHDL particles and, importantly, changes to the conformation of ApoA-I, potentially affecting its ability to mediate the incorporation of cholesterol and its subsequent biochemical processing.
This project will apply molecular dynamics simulation approaches to characterise the self-assembly of rHDL particles of different lipid composition to investigate changes to their structure and, in particular, the structure of ApoA-I. The predicted properties of these rHDL particles will be used to rationalise their biological properties and therapeutic potential.

How does cryopreservation damage cell membranes?

Cryopreservation (the storage of cell and tissues at liquid nitrogen temperatures: -196°C) requires the use of so-called cryosolvents to promote the vitrification of water to minimize ice formation. Cryosolvents such as DMSO, glycerol and ethylene glycol can cross cell membranes, inducing vitrification inside cells. These agents, however, are toxic to cells and can indeed damage cell membranes themselves by changing their structure and functionality.

This project will use molecular dynamics simulations to predict the changes to the structure and stability of model cell membranes in the presence of aqueous solutions of different polyalcohols and sugar alcohols commonly used in cryosolvent mixtures, such as ribitol, xylitol, inositol, erythritol, mannitol and sorbitol. Elucidation of the mechanism of interaction of such poly-hydroxylated molecules with cell membranes will allow the future rational design of optimal multi-component aqueous mixtures of cryosolvents with improved cryopreservation properties. This will have applications in areas as diverse as the freezing of eggs and embryos and the preservation of germplasm from endangered plants.

How does the crowded environment in the cytoplasm affect the structure and stability of proteins?

The cell cytoplasm is highly packed due to the large amount of macromolecules (e.g. proteins, nucleic acids) as well as other biomolecules and ions present. This phenomenon is commonly referred to as macromolecular crowding, and gives rise to an excluded volume effect, which effectively compresses proteins, reducing their average dimensions and favouring their native folded states. The effect of macromolecular crowding can thus affect significantly the biological function of proteins by modifying their conformations.
Molecular dynamics simulations will be used in this project to investigate the self-crowding of the regulatory protein calmodulin in an aqueous environment, and how it affects its native structure and thermal stability. The data generated will provide a molecular rationale for small angle neutron scattering (SANS) experiments being carried out by collaborators at the Australian Nuclear Science and Technology Organisation (ANSTO) in Sydney.

Understanding the mechanism of self-assembly of endocannabinoid-based lipid nanoassemblies for the delivery of drugs

Chronic inflammatory disease often leads to pain and dysfunction. Recently endocannabinoid-based lipid nanoassemblies have been developed as delivery vehicles for drug molecules. These systems have the advantage of being fully biocompatible due to the endogenous nature of the lipids used, and can be used for the controlled delivery of hydrophilic, hydrophobic and amphiphilic drug molecules.
Molecular dynamics simulations will be used in this project to characterise the mechanism of self-assembly of endocannabinoid-based lipids and their structure at different temperatures and levels of hydration. The outcomes of this study will facilitate the rational design of more effective nanoassemblies with optimal drug-carrying properties.

Mathematical Physics

Students interested in computational or theoretical physics are encouraged to consider projects in the Theoretical Physics Group. This is a research intensive group, which was (2007-2013) a node of the ARC Centre of Excellence for AntimatterMatter Studies. It specialises in the field of Quantum Collision Physics. Such processes occur all around us, and include all chemical reactions. More specifically, our area of expertise is for projectiles, which include electrons, positrons, photons, protons and antiprotons, colliding with atoms, ions and molecules. Applications include astrophysics, fusion energy, lighting, material and medical diagnostics.

Presently, there is considerable demand from astrophysicists and fusion physicists for the generation of electron/positron-atom/molecule collision data. Depending on the student’s background knowledge and scope of the project, individual research projects will range from data generation and evaluation, utilising super computer facilities, through to extending the computational capacity to be able to tackle new collision problems. The expectation is that the research outcomes would be published in the best physics journals. The specific details of the project will be determined by discussion with the particular staff of the Theoretical Physics Group. Some examples are listed below.

Prof Alisher Kadyrov and Prof Igor Bray

Physics of proton therapy

Proton therapy is used to destroy deep-seated cancer cells. It can precisely target the location, size and shape of the tumour, limiting damage to surrounding healthy tissue. When fired into living tissue, a beam of protons deposits most of its energy at a very specific depth that depends on its initial energy. This makes minimal damage to surrounding organs in front of the tumour while delivering almost zero radiation after the tumour. Such precision is not possible with other radiation treatments such as X-ray therapy. Proton therapy requires careful treatment planning based on theoretical depthdose simulations with a mm accuracy. The aim of the project is to develop a practical, efficient, and accurate theory of heavy ion collisions with biologically important molecules and provide a computer code for radiation dose calculations in hadron therapy of deepseated cancerous tumours.

Objectives:

  • Review the literature.
  • Learn how to use supercomputers to run locally developed codes.
  • Calculate stopping power for protons in soft and hard tissue.

Prof Alisher Kadyrov and Prof Igor Bray

Antihydrogen formation in antiproton collisions with rydberg positronium

Cross sections for antihydrogen formation are of particular interest to the ALPHA collaboration, which requires the production of near zero energy antihydrogen. Production of slow antihydrogen atoms is one of the prerequisites for experimental verification of the materantimater equivalence principle. There are two experiments with antihydrogen planned for the near future at CERN, AEGIS (Antihydrogen Experiment: Gravity, Interferometry, Spectroscopy) and GBAR (Gravitational Behaviour of Antihydrogen at Rest). The aim of these experiments is to measure the freefall of antihydrogen in order to make direct measurements of the freefall acceleration constant of antimatter in the gravitational field of Earth. To observe the free fall the antihydrogen has to be created at rest or cooled to extremely low energies (a few neV). With new developments in antiproton cooling techniques cryogenic temperatures became achievable.

Therefore, formation of antihydrogen in ultra-low energy positronium-antiproton collisions with its very large cross section emerges as a primary source of antihydrogen. Antihydrogen can be created with the use of antiprotonpositronium collisions. Large cross sections are achieved when positronium is in a Rydberg state. The aim of the project is to use the two-center convergent close coupling (CCC) method to model antiproton collisions with Rydberg positronium and calculate the antihydrogen formation crosssections at ultra low energies.

Objectives:

  • Review the literature.
  • Learn how to use supercomputers to run locally developed codes.
  • Calculate total cross sections for antihydrogen formation at low energies.

Prof Igor Bray and Prof Dmitry Fursa

Collision data for modelling of fusion plasma (ITER)

The Theoretical Physics Group has been engaged in the biggest scientific research project on the planet, which is the building of the next generation fusion reactor known as ITER, see http://iter.org. The goal is to produce fusion energy as it happens deep in the core of our Sun. Our contribution has been to provide collision data of interest to the plasma modellers who are trying to understand all of the physics that will follow the fusion process.

Recent example is beryllium: it has been determined that beryllium will be a substantial component of the first wall, and hence reliable electronimpact cross sections for this atom and all of its ions are required by the modellers. Collision data for many more atoms and molecules are required for modelling the ITER plasma. Our aim is to develop a computer code that is capable to model collisions with a much wider number of atoms and molecules than the present version of the CCC code allows for.

An even more difficult task is to extend the CCC code to study collisions with molecules. We are especially interested in the molecules that are present in ITER plasma: BeH, BeH2, Li2, Li_H, etc. We have already developed a computer code that produced the best in the world result for H2+ and H2 molecules and now aim to extend it to more complex systems.

This project will contribute to the International Atomic Energy Agency fusion research and will be our contribution to the Coordinated Research project (CRP): “Atomic data for Vapour Shielding in Fusion Devices”.

Here are theoretical and code development projects that you can participate:

Electron collisions with atoms

The project aims to provide a comprehensive set of collision data for electron collision with tin and gallium atoms. We will use the relativistic formulation of the CCC method (RCCC)  as Ga and Tn are relatively heavy atoms. Both atoms have p-electron in the open shell, one for Ga and two for Tn, and show substantial fine-structure splitting that indicates that relativistic effects will play important role in modeling of atomic structure and collision processes.

Electron collisions with molecules

The present version of the CCC code will be extended to more complex molecules, such as Li2, LiH, etc. The aim is to provide a comprehensive set of collisions data relevant for fusion research. This includes a set of elastic and momentum transfer, ionization, excitation and dissociation cross sections. The study of nuclear motion will allow us to provide a set of fully vibrationally resolved cross sections.

Objectives:

  • Understand what ITER is all about.
  • Understand the physics and the mathematical model behind the computer code.
  • Learn how to use supercomputers to run locally developed computational codes to determine the required data to a required accuracy.
  • Disseminate the data to existing databases for ready access to fusion researchers worldwide.

Prof Igor Bray and Prof Dmitry Fursa

Positron collisions with atoms and molecules

Modelling positron transport in various media is of immense importance for applications as diverse as atmospheric and astrophysical research and studies of radiation damage in tissue. Accurate modelling requires accurate collision data: cross sections for all relevant collision processes. We have developed the best in the world computer code (CCC) to model positron collision processes. The next step is to make the code more general and capable to model collisions with arbitrary atom or molecule. We will have a special emphasis on study of the collisions with biologically important atoms and molecules.

Objectives:

  • Review various applications of positrons
  • Understand the physics and the mathematical model behind the computer code.
  • Learn how to use supercomputers to run locally developed computational codes to determine the required data to a required accuracy.
  • Disseminate the data to existing databases for ready access to researchers worldwide.