Nimrod (National Institute Machine Radiating on Downs, "the Mighty Hunter" Nimrod; name attributed to W. Galbraith) was a 7 GeV proton synchrotron operating in the Rutherford Appleton Laboratory in the United Kingdom between 1964 and 1978. Nimrod delivered its last particles at 17:00 hrs on 6 June 1978. Although roughly contemporary with the CERN PS its conservative design used the "weak focussing" principle instead of the much more cost-effective "strong-focussing" technique, which would have enabled a machine of the same cost to reach much higher energies.
Nimrod was dismantled and the space it occupied reused for the synchrotron of the ISIS neutron source.
The magnet power supply included 2 motor-alternator-flywheel sets. Each drive motor was 5,000 HP. Each flywheel was 30 tonnes. Each alternator was 60 MVA 12.8kV. Magnet currents would pulse at 10,550 A.