Dr Pablo Bilbao, Leverhulme-Peierls Fellow in Theoretical Physics at Lady Margaret Hall, has been awarded a prestigious PhD Research Award from the Plasma Physics Division of the European Physical Society (EPS).
The EPS recognises up to four early-career scientists each year for truly outstanding research achievements associated with their doctoral study in the field of plasma physics.
Dr Bilbao’s thesis, ‘Kinetic instabilities in extreme plasma physics: laboratory and astrophysical dynamics’, studies how matter behaves under some of the most extreme conditions in the universe. One such example can be seen around neutron stars, where particles move close to the speed of light and radiate enormous amounts of energy. In these environments, ordinary matter can turn into electron-positron ‘pair plasmas’, which behave very differently from the plasmas encountered on Earth.
“One of the big open questions in astrophysics is how these systems produce incredibly bright, coherent radio flashes, such as those seen from pulsars and Fast Radio Bursts,” explains Dr Bilbao. “I developed a theoretical understanding showing that when a very hot plasma cools by radiating energy, the particles naturally reorganise themselves into an unstable configuration, which was confirmed using some of the largest computer simulations of this kind of plasmas. The resulting plasma is unstable and can efficiently convert particle energy into intense, highly ordered radio waves. In other words, the act of cooling can itself trigger the mechanism that produces the radiation. I also showed that closely related physics appears in next-generation particle accelerators, where high-energy beams emit radiation as they travel through plasma. There, radiation can reshape the beam in a similar way, potentially enabling new sources of coherent light in the laboratory.”
Dr Bilbao also worked with the CERN Fireball experiment, led by LMH Fellow and Tutor in Physics Professor Gianluca Gregori and LMH alumnus Dr Charles Arrowsmith, which achieved the first laboratory creation of a relativistic electron-positron pair plasma. He led large-scale computer simulations to interpret the experiment and determine which plasma instabilities should occur under realistic conditions, helping to establish the first experimental constraints on how such pair plasmas behave.
