The particle physicist Donald Perkins, who has died aged 97, made seminal discoveries about the structure of the proton, and nuclear interactions at extreme energies, and first proposed the use of beams of pion particles in cancer therapy. His career spanned the birth of particle physics, as it emerged from studies of cosmic rays in the 1940s, through its maturation in the final decades of the last century, to the climactic discovery of the Higgs boson in the 21st. He played key roles throughout.
When Perkins began research in 1948, the electron, proton and neutron were the only known fundamental particles whose role in building atoms was understood. The pion, a particle predicted to carry the strong force that binds atomic nuclei, had recently been discovered in cosmic rays by Cecil Powell of Bristol University, and it was in Powell’s group that Perkins began his research career.
