I am always looking for motivated students interested in extragalactic astronomy to work on Masters by research and Doctor of Philosophy (PhD) projects.
Deadlines for Expression of Interest are generally twice per year (March/April-September/October).
The next deadline is on March 1, 2019. Please see this link for more details on how to apply.
Below you find some of the highest priority projects offered by our research group, but I am always happy to discuss possible projects on galaxy evolution. Feel free to contact my via email.
Galaxy Transformation in the Local Universe
One of the most outstanding challenges in extragalactic astronomy is to identify the astrophysical processes responsible for transforming simple gas clouds into the heterogeneous population of galaxies inhabiting today’s Universe. How did galaxies of different types form and evolve? Does the environment where a galaxy lives influence its evolution? Inevitably, the answers to these questions entail a detailed investigation of all the components of the interstellar medium (gas, dust, metals) and their relation to stellar properties, kinematics and environment. This clearly requires multi-wavelength information for statistically significant samples of galaxies across the cosmic web, which are becoming available only now. In particular, until very recently, astronomers have struggled to understand the link between stellar and gas kinematics, morphology and star formation.
In this project, the student will take advantage of data from the largest optical integral-field spectroscopic survey to date (the SAMI Galaxy Survey and the MANGA survey) to determine how the kinematical properties of galaxies influence galaxy evolution. S/He will establish if morphological transformations are always driven by a change in the kinematical properties of galaxies and will quantify the link between stellar and gas kinematics and star formation efficiency in galaxies across environments. This project is mainly observational, and the student will acquire skills in reduction and interpretation of multi-wavelength data. Moreover, the student will have the opportunity to collaborate with the theory group at ICRAR to compare his/her findings with the predictions from the most advanced cosmological simulations.
The connection between dark and visible matter in nearby galaxies
The dynamical mass of galaxies represents the best way to quantify the total matter (visible+dark) locked into halos. It can then be used to quantify the role of dark matter in driving the collapse of baryons and the efficiency of this process. In the past, dynamical masses have mainly been estimated by using either measures of the rotational velocity of gas, or dispersion velocity of stars. However, in galaxies gas and stars are supported by both random and ordered motions, and the balance between rotation and dispersion depends on the morphology of galaxies. Thus, it is vital to include both quantities in the determination of dynamical mass. Thus, it is far from trivial as it requires resolved velocity maps for galaxies of different types.
In this project, the student will take advantage of optical integral field spectroscopic data obtained as part of the SAMI survey to test a novel technique to combine rotation and dispersion velocity and determine homogenous dynamical mass measurements for a uniquely large sample of galaxies. The student will become a member of the SAMI survey team, gain extensive familiarity with observational astronomy and, depending on performance, could have the chance to also compare the results with the predictions of theoretical models. This project is mainly observational, and the student will acquire skills in reduction and interpretation of multi-wavelength data. Moreover, the student will have the opportunity to collaborate with the theory group at ICRAR to compare his/her findings with the predictions from the most advanced cosmological simulations.
Looking at galaxy morphology with HI glasses
Thanks to the incredible progress done by optical astronomy in the last decades, we now have an accurate characterisation of how the stellar distribution of galaxies vary with mass and environment. We know for example, that more massive galaxies have larger radii and higher central stellar concentrations. At fixed mass, the size and stellar density vary with morphology, and the slope and scatter of these relations vary with environment. The calibration of these “scaling relations” had an immense power in improving our understanding of how galaxies form and evolve.
However, galaxies are not only made of stars. Another key component of galaxies is cold gas, which represents the fuel for future star formation. Is the distribution of gas similar to that of stars? Does the size of the gas disk always increase with mass? Or do gas disks all have the same structure? Surprisingly, we do not know the answers to these questions yet.
In this project, the student will start working on archival data for hundreds of galaxies in the local Universe and gradually incorporate observations obtained as part of the WALLABY survey on ASKAP to characterise for the first time the HI structural scaling relations across the entire Hubble sequence. This work will set the foundation and develop the tools needed for the future exploitation of data obtained with the Square Kilometre Array and its precursor telescopes.