Mr Jamie McGregor

I am a final-year Masters student at ICRAR-UWA, currently working on a project using the new MUSE and ALMA Unveiling the Virgo Environment (MAUVE) survey. Clusters (like Virgo) are groups of hundreds or thousands of galaxies packed into a very small region – they are some of the most extreme environments in the Universe, and can change the course of a galaxy’s evolution. In particular, I am looking at quenching in these galaxies – how does the Virgo Cluster remove gas and stop star formation in these galaxies?

One of the most important quenching processes in clusters is ram-pressure stripping – as a galaxy moves at high speed through the cluster, it experiences a pressure force – like the ‘wind’ you might feel if you stick your hand out of the window of a moving car! If strong enough, this wind can remove a galaxy’s gas – the fuel for its star formation.

My research has focused on IC 3392, one of the first MAUVE galaxies observed. It is a fairly small, unremarkable galaxy, except that most of the galaxy has almost no gas, likely due to ram-pressure stripping! My main goal has been to make star formation histories for different regions IC 3392, by studying the spectra from the galaxy today, and trying and work out what was going on in its past – a Virgo Cluster ‘crime scene investigation’, so to speak. Reconstructing a galaxy’s past is something of a dark art, and so I’ve spent considerable time trialling different methods and comparing their results.

There is a lot of interesting science that can be done with MAUVE data, which consists of images of each galaxy at thousands of different optical wavelengths. I’ve also done some work investigating the emission from hot, ionised gas in the galaxy, to see how temperature, density, and ionisation vary across IC 3392. This has produced some fascinating results on how gas can return to galaxies after ram-pressure stripping, which I aim to study in more detail in coming months!

Prior to my Masters, I completed an Honours in Mathematics and Statistics, where I used network science techniques to analyse and classify classical music. I have also completed summer projects at ICRAR-Curtin and OzGrav’s UWA node.