A gamma-ray tracking system involves measuring the position and energy of every gamma-ray interaction in a detector so that the path and sequential energy loss of a single gamma-ray can be deduced using the Compton scattering formula.

The full energy of the event can then be reconstructed without the losses due to suppression shields (figure top right), which covered nearly half the solid angle in the previous generation of spectrometers. The realisation of such a system will require highly segmented germanium detectors (figure bottom right) and digital electronics to extract energy, time and position information using pulse shape information.

This radically new device will constitute a dramatic advance in gamma-ray detection that will have wide ranging applications in medical imaging, astrophysics, nuclear safeguards and radioactive waste monitoring, as well as introducing a new plateau of detection capability for nuclear structure studies.

Find out more about the UK Gamma Ray Tracking Project:

• The UK GRT website (external link)