Diamond Annual Review 2023/24

61 D I A M O N D L I G H T S O U R C E A N N U A L R E V I E W 2 0 2 3 / 2 4 however an increasing number of operational problems with the analogue- to-digital (ADC) controller cards used in the power supply control system, as well as obsolescence, has required that an alternative be developed. The replacement cards (Fig. 6), developed in-house over several years, have higher precision and can be reprogrammed in the future to work with Diamond-II Increasing redundancy in the linac Significant progress has been made with the SLED (Stanford Linac Energy Doubler) cavity project on the Diamond linac. This project will increase the resilience against amplifier failure by only requiring one klystron instead of two to generate the necessary power to accelerate the electron beam to 100 MeV. By reconfiguring the layout of the waveguide network, it is now possible for RF power to go from either of the two klystrons through waveguides switches into all four accelerating structures (two pre-bunchers and two main accelerating structures). Fig. 3 shows the change in the waveguide configuration, Fig. 4 the new installation and Fig. 5 oscilloscope traces of the output power pulses. Successful operation of the linac at 100 MeV has been demonstrated on several occasions with a single klystron. Overcoming obsolescence and improving power supply reliability The number of beam trips due to power supply faults remains very low, Figure 3. The previous waveguide configuration (left) versus the new configuration including the SLED cavity (right). Figure 4. The newwaveguide and SLED cavity arrangement in the Linac. Figure 5. Output from the klystron (left) and input to the bunchers and accelerating structures (right) following the SLED cavity. The RF pulse width from the klystron is 5 μs long while the higher power pulse going to the linac structures is 1 μs long.