Research Fellows Directory
Dr Rhaana Starling
University of Leicester
Gamma-Ray Bursts (GRBs) are the most powerful explosions in the Universe, second only to the Big Bang itself! For a brief time GRBs can outshine a billion galaxies and release as much energy in 10 seconds as the Sun will release over its entire lifetime, and are the most distant known objects. So what causes them?
The origin of many GRBs may be explained by the explosive death of a star tens of times more massive than our Sun. The star's core collapses in a supernova event, likely forming a black hole and releasing very fast jets. The GRB light we observe comes from shock fronts within these jets.
Exactly which stars can produce GRBs, and how these events have evolved - from the emergence of the very first stars and galaxies to the present day - are of great importance in the quest to reveal the history of our Universe.
There is also an urgent need to understand how the GRB jets themselves are launched from the black hole. Knowledge of this mechanism will impact on all astrophysical sources that possess jets, and the relativistic nature of GRB jets enables tests of fundamental physics in the extreme regime.
The fleeting nature of these unimaginably powerful events attracted me to this field of science: GRBs can happen at any time in any direction and catching them has been a major technological challenge. I am using the Swift satellite comprising cutting-edge technology to scan the sky and turn swiftly round to pinpoint the cosmic explosion. The fading embers of the explosion can be subsequently followed-up with large telescopes on the ground. These observations, together with theoretical modelling efforts, are paving the way for a deeper understanding of our extreme Universe.
Interests and expertise (Subject groups)