Area of research: High Energy Particle Physics

What led you to pursue a postdoctoral position in Physics at U of T?

For a particle physicist working on Dark Matter, Toronto is a great location. The experimental group at the University has a wide array of expertise (from hardware, to simulations, to statistics and analysis), plus it is close enough to SNOLAB to make access to the experiments there much more painless than other places. That, in combination with the fact my family is originally from the area, made it the perfect choice for me.

Where did you complete your PhD? What was the topic of your PhD thesis and why?

I did my PhD at the University of Melbourne, Australia. My thesis was on designing an experiment, SABRE, to test the hypothesis that a modulating signal observed by another experiment (DAMA/LIBRA) for around 20 years was from Dark Matter. Such a test is useful to do in Australia, as any modulation caused by the seasons would be flipped, while Dark Matter modulation would look the same.

Could you describe the focus of your current research as a postdoc? What inspired or motivated you to pursue this specific research area?

I’m still working in the Dark Matter field, but on a different experiment: SuperCDMS. This is a cryogenic detector with sensitivity to very low energy depositions. It is designed to be one of the most sensitive detectors to low mass (<10 GeV/c2) to date. I knew I wanted to join SuperCDMS after my PhD because of the detector technology and set up used. There are effectively 4 different types of Dark Matter sensors in a single experiment, which means if we do see events that are consistent with Dark Matter we are uniquely positioned to do internal consistency checks with different types of targets and be more certain about what it is we’re seeing. Couple this with the very cool (pun intended) cryogenic set up it’s an amazing piece of equipment to work on.

Most of my work to date has been assisting in the installation and commissioning of the experiment as we get it all set up, and modelling the radioactive background sources we see so that we can perform a robust statistical analysis once the data starts flowing in.

Have you collaborated with other researchers or departments during your postdoc? How have these collaborations enhanced your research?

The nature of experimental particle physics means you are always collaborating with a larger group. There are around 30 different institutions involved with SuperCDMS spread across North America and Europe, each with their own areas of expertise required to make everything work. Personally, I have worked very closely with SNOLAB and SLAC during the installation phase. I have also worked with nuclear theorists from the Australian National University (ANU) on how uncertainties in nuclear structure might impact how well we can constrain our knowledge of Dark Matter.

How do you believe your research contributes to the broader field or addresses current challenges?

Understanding the nature of Dark Matter is probably one of the most fundamental questions in particle physics at present. We know this particle exists, otherwise the universe wouldn’t have evolved the way it did, and galaxies would move very, very differently, and yet no one has observed it directly yet. We need to do this to make progress in understanding this particle, which makes up about 25% of the universe. SuperCDMS is probing a new regime of Dark Matter candidates, meaning no matter what we see we will help answer the question of what Dark Matter might be, and what it’s not.

What challenges have you encountered in your research, and how have you worked to overcome them?

I am someone that likes being able to understand the big picture and see how all the small moving parts fit together – I think this is part of the appeal of particle physics for me. But on an experiment like this there are so many technical, moving parts that go on and it’s impossible to be an expert in all of them. In that sense, one of my biggest challenges has been learning to be okay with not knowing everything and trusting in the expertise and experience of my collaboration when making decisions.

In what ways has your postdoctoral experience contributed to your professional development?

I have been very lucky to have the opportunity to travel extensively during my postdoc – both for international conferences and also getting to spend hands on time with the detectors. But hands down the biggest contribution to my professional development is in the leadership roles I have been able to take on within the collaboration. I am one of the Run Coordinators for the commissioning phase of the experiment, meaning I am responsible for the day-to-day operation of the detectors, as well as longer term planning for tests that need to be done and data that will be taken. This has given me the chance to exercise a level of leadership, scheduling, and communication that I have never done before, and I have grown significantly because of it.

What are your future career aspirations after completing your postdoc?

I would love to follow the faculty track and get a lecturer position somewhere. Ideally this would be a position that allows me to continue my involvement with SuperCDMS while also thinking about the future direction of Dark Matter research, and what the next generation of experiments will look like. As the biggest, Xenon based detectors approach the neutrino floor it feels inevitable that the field will start pursuing new and interesting ways to look for Dark Matter, and I’m hopeful my experience in cryogenics experiments lends itself to this.

What advice would you give to graduate students or early-career researchers considering a postdoc? Are there lessons learned during your postdoc that you believe would be valuable for others in the field?

You are never going to be able to know everything, but it is important to stay curious and keep asking interesting questions. For me, communication and collaboration with other people is a priority – I may have blind spots in my expertise or experience that I’m not even aware of and you don’t find those out until you talk to other people.