newsletter september 2021 cher cavities, and a DTL (Drift Tube Linac) consisting of 5 tanks. The normal conducting linac will be powered by nine RF power sources operating at 352.21 MHz. The RF system can be defined as all the components and subsystems needed to generate and deliver RF power to the cavities between the wall power plug (AC power from the grid) and the cavity power coupler (at the cavity input). The complete chain includes pulsed high voltage sources (or modulators), high power ampli fiers, waveguide or coaxial RF distribution systems and Low Level RF control systems (LLRF). ESS Bilbao’s tasks included the design and prototyping, Courtesy of ESS procurement, integration, factory testing, transporta tion, delivery and finally the supervision of the installa tion and assistance with the commissioning of the RF stations at the ESS site in Lund (Sweden). The integration of the RF power stations was success Co-funded by European fully carried out by the team headed by Morten Jensen. Regional Development RF TEST STAND Funds under the FEDER TRACKS Soon,ESS Bilbao undertook the development and project (Transmisores de RF para commissioning of a High-Power RF Test Stand (RFTS). Aceleradores basados en Klystrons y Estado Sólido) RF SYSTEM SCOPE • Generate the required RF power to properly accelerate the charged particle beam inside the cavities. The RFTS comprises a complete RF transmitter chain of up to 3 MW at 352 MHz, much like the ones for Maintain the amplitude and phase the ESS LINAC. That includes a modulator, a klystron • with all its ancillaries and waveguide components. Be stability of the accelerating field sides, a large deionized water-cooling system is requi red, as well as low-level RF generation and distribution within a given tight tolerance and specialized RF measurement equipment. The RFTS to accelerate the particles with is installed inside a fence enclosure (to avoid electric, non-ionizing and ionizing radiation risks), and it is fully minimum degradation of beam operated from a control room. quality. The RFTS has been instrumentalin testing and vali dating high power klystrons, several types of wave Protect the machine itself from any guide components and the buncher cavities and their • power couplers. Eventually, it will serve as the RF failure. power source for the ESS Bilbao RFQ currently under construction. 7