• C. Christou
  Diamond, Oxfordshire

The Diamond Light Source injection system consists of a 100MeV linac and a 3GeV full-energy booster. The injector is used to fill the storage ring from empty and to provide beam for a 10 minute top-up cycle. The high power RF for the linac is generated by two S‑band klystrons, the first powering a buncher and accelerating structure, and the second feeding a second accelerating structure. With the klystrons feeding the two accelerating structures independently, a failure in the klystron or modulator feeding the lower energy structure and bunchers renders the linac, and hence the injection system as a whole, inoperable. In order to address this problem, the RF feed to the linac has been reconfigured to enable either klystron to power the first structure and bunchers; this has involved a rebuild of the waveguide network in the linac vault to include two four-way S-band switches, and the development of a lower energy operating mode for the linac, booster and linac-to-booster transfer line. Details are presented in this paper of the installation and test of the switching network, and the first results are reported of the new operating mode.