Peter Twin has made important contributions to nuclear spectroscopy. He combines a flair for instrumental development with a deep understanding of nuclear structure and a clear appreciation of the problems to which a new detector system may be applied.
In early work, he demonstrated the value of correlation experiments in determining nuclear properties. He played a major part in the development of suppression shield spectrometers (TESSAs) for the study of high angular momentum states.
Peter then showed that at high spin the nucleus dysprosium-152 became superdeformed with a 2 to 1 semi-axis ratio. He led the UK team that played a major role in developing and building the European EUROBALL gamma ray detector array.