Sarah Gregg
(PhD student 10/21- 2025, viva pending)

Sarah graduated 1st-class MSci Theoretical Physics, obtaining the
Raymond Flannery prize (for top student in Applied Mathematics or Theoretical Physics) and the William Blair Morton prize (for best undergraduate research project). She joined the group in Oct 2021. She is a member (PhD representative) of the Institute of Physics Ireland Committee. Sarah is developing and applying many-body theory methods for positron scattering and annihilation gamma spectra on molecules.

Sarah has submitted her thesis and is awaiting her viva (thesis defence).

Dr Brian Cunningham (group member 04/2019 — 06/2024) now Research Software Engineer at QUB.

Brian is a lead developer of our EXCITON+ code for positron interactions with molecules and condensed matter. He graduated MSci and PhD from Queen’s University Belfast. He has expertise in computational condensed matter physics. He previously incorporated vertex corrections in the Questaal code.

Brian is a lead developer of our EXCITON+ code for positron interactions with molecules and condensed matter. He graduated MSci and PhD from Queen’s University Belfast. He has expertise in computational condensed matter physics. He previously incorporated vertex corrections in the Questaal code.

He was official Assistant Supervisor for PhD graduate Dr Jaroslav Hofierka. Brian was awarded the 2023 QUB Postdoctoral Development Centre Research Prize. He is now a Research Software Engineer at Queen’s University’s High-Performance Computing team.

Dr Charlie Rawlins (group member 10/2019 —2022), now Research Fellow at QUB.

Charlie joined the group following a BSc in nanotechnology and PhD in theoretical physics from Curtin University in Perth, Australia with the theoretical physics group headed by Igor Bray, Alisher Kadyrov and Dmitri Fursa. His thesis concerned positron and positronium scattering on atoms with a focus on anti-hydrogen formation. He has expertise in theoretical atomic physics and positronium. With us he worked on many-body theory for positron-molecule interactions, notably being first-author on a PRL for positron scattering and annihilation in H2, N2 and CH4. He successfully obtained a 4-year position on a US-Ireland project in molecular dynamics at QUB.

Dr Andrew Swann [alumnus]
(group member 10/2020-08/2022, Visiting Scholar 2023-2024), now a Mathematics Teacher at Belfast Royal Academy Grammar School.

Andrew graduated MSci Mathematics (receiving the Royal Irish Academy “Hamilton Prize” for the best mathematics students in Ireland, in addition to numerous QUB examination prizes) and PhD in Theoretical Atomic Physics from Queen’s. He has expertise in theoretical and computational atomic and molecular physics, including positron and positronium interactions with atoms and molecules. He has made significant contributions to our EXCITON+ code, including developing capability to calculate the Doppler-shifted spectrum of gamma rays emitted during positron annihilation with atomic/molecular electrons (paper in preparation). He also developed our ANTICOOL Monte Carlo code to model positron cooling in the buffer gases N2 and CH4 (used ubiquitously in positron traps) including positron-positron interactions and showing their effect on the positron momentum distribution and cooling dynamics. He is currently undertaking a Postgraduate Certificate in Education (PGCE) at QUB to qualify as a Mathematics teacher.

• Jaroslav Hofierka
  PhD (10/2019 — 12/2024); now (12/2024-) a postdoc with Prof Lorenz Cederbaum at the University of Heidelberg (Germany).
  
  Jaroslav obtained a BSc in Physics and Masters degrees in Theoretical physics at the Charles University, Prague, Czech Republic. During his PhD he developed ab initio methods for positron-molecule interactions, in particular positron binding to molecules in our EXCITON+ code.
  
  Jaroslav was awarded first-prize in the 2024 Milan-Odenhal award of the Czech Physical Society for outstanding research by those under 30, “for his contrbutions to developing the pioneering many-body theory description of positron-molecule interactions”.
  
  

• Jack Cassidy
  PhD (10/2020 — 06/2024); now a Statistician at the Northern Ireland Statistical Research Agency (NISRA).
  
  Jack was born and raised in Belfast, graduating 1st class Applied Mathematics and Physics at Queen’s (2020), receiving the William Blair Morton Prize and the Philip Burke Memorial Award. He obtained Associate Fellowship of the Higher Education Academy in 2022. His PhD focussed on developing and applying ab initio many-body theory to explain trends in positron binding energies in molecular families, extending the many-body theory to annihilation gamma spectra in molecules, and calculating the stability of positronic-bonded molecules (e.g., predicting the stability of new positronic-bonded molecular dianions).
  
  

• Dr David Waide
  PhD in Theoretical Physics, graduated 04 July 2023, then a Research Associate in the Electronic Structure Group, School of Physics, Trinity College Dublin.
  Thesis title “Many-body theory of positron interactions with atoms and atomic clusters”.
  
  
  
  
  

• Dr Chris Emerson: graduated PhD in Pharmacy 2020; primary supervisor Prof. Jonathon Coulter (QUB Pharmacy); second supervisor Dr Dermot Green. Now a Scientist at Celerion.