Welcome to the University of Sydney’s Astroparticle physics group, led by the Head of the School of Physics Prof. Céline Bœhm. We conduct research that connects the otherwise disparate worlds of astronomy, particle physics, and cosmology. We are principally interested in studying some of the most important issues with our understanding of the Universe, such as the identity of dark matter, the conditions of the early Universe, the formation of large scale structure, the properties of high energy cosmic rays, and the nature of gravity.

We are one of the five nodes of the ARC Centre of Excellence for Dark Matter Particle Physics (CDMPP).

We also overlap in membership with the Sydney Institute for Astronomy (SIfA), the Particle Physics group, and a Sydney-UNSW joint venture: the Sydney Consortium for Particle Physics and Cosmology (CPPC).

On this website, you can find information about our members, our research, as well as opportunities to join our research group or study with us.

Group news


  • Learn more about the SABRE South experiment in this article in The Saturday Paper for which Theresa was interviewed.
  • Ciaran appeared in ABCs “Elevator Pitch” series, attempting to explain antimatter in an elevator ride.
  • Welcome to Maria Chiara Lisotti who has joined the group as our newest PhD student!
  • Congratulations to Theresa for being selected to take part in the Homeward Bound leadership initiative, including voyaging to Antarctica.
  • Congratulations to Celine for being named one of Australia’s 50 women at the cutting edge of science in Australia


  • Celine has now concluded her time as the Head of the School of Physics and has passed the baton to Prof. Tara Murphy.
  • Celine has won the Australian Institute of Physics Women in Leadership medal! Congratulations, Celine! The medal is given in recognition of Celine’s excellence in academic research and leadership of large international collaborations, for her distinguished role in shaping astroparticle physics research in Australia, exemplary academic mentorship and her outstanding performance as a Head of School, which resulted in an inclusive, supportive and transparent workplace environment in the School of Physics at the University of Sydney and, notably, a significant increase in the number of female academics and professional staff and mid and early career researchers in leadership roles.
  • The group is heading to the Dark Side of the Universe 2022 conference at The University of New South Wales! Theresa, Ellen and Markus all gave talks at the conference.
  • We hosted the Sydney Spring School on Particle physics and cosmology, a three-day long school attended by around 40 students. Ciaran and Theresa both gave lectures at the school.
  • Ciaran, Markus, Ellen and Theresa all attended the Centre of Excellence for Dark Matter Annual Meeting in Geelong. All four gave talks at the meeting and Markus won the 2022 Collaboration and Centre Values Award!
  • Ellen Sirks has joined us as our new postdoc. Ellen recently finished her PhD at the University of Durham and works on dark matter simulations.
  • Dr Ciaran O’Hare and Dr Theresa Fruth organised and spoke at a public outreach event for the international Dark Matter Day
  • We have a new member! Dr Theresa Fruth has recently joined us as a lecturer. She is as a member of the LZ collaboration and will be helping to grow our experimental particle physics research here at Sydney.
  • Zac Picker has now sadly left our group, but is going on to an exciting postdoctoral position at UCLA. We wish him the best of luck in his future career!
  • Markus Mosbech gave a seminar on “Dark matter microphysics with next generation observatories” for the ICAP seminar series
  • Ciaran O’Hare gave a talk on “Dark matter in the Milky Way and implications for wave-like dark matter experiments” at the BREAD Collaboration meeting.
  • Ciaran O’Hare gave the concluding talk at the Identification of Dark Matter (IDM) conference in Vienna. His slides can be viewed here.
  • Zac Picker has been awarded his PhD in physics with a thesis entitled The gravity of particle physics: dark matter, black holes, and axionsCongratulations Dr Picker!
  • Ciaran O’Hare and Celine Boehm’s recent publication “Particle detection and tracking with DNA” was featured in an article in the New Scientist


  • Ciaran O’Hare’s recent article “New definition of the neutrino floor for direct dark matter searches” was selected as a highlighted article and Editor’s suggestion in Physical Review Letters
  • Celine will be giving a seminar at the IAP, and will also speak at the Light Dark World 2021 international forum
  • Zac gave a talk and presented a poster at AstroDark-21
  • Dr Ciaran O’Hare has been awarded a $400,000 DECRA for the project “Unmasking dark matter: from the laboratory to the Milky Way”.
  • The group attended the Dark Matter Centre’s Annual workshop, in which Zachary Picker gave a talk on his work on the “companion axion model”. Zac and Markus also both presented posters at the meeting.
  • Zac Picker gave a seminar for our CPPC series on his PhD work, which can be viewed here
  • Ciaran O’Hare is giving seminars at Tsung-Dao Lee Institute, Melbourne University, UC San Diego, University of Goettingen, and Nanjing Normal University on his recent work on the neutrino fog.
  • Group website created!