The ESS accelerator high level requirements are to provide a 2.86 ms long proton pulse at 2.5 GeV at repetition rate of 14 Hz. This represents 5 MW of average beam power with a 4% duty cycle on target.
The ion source (ISRC) produces a proton beam that is transported through a Low Energy Beam Transport (LEBT) section to the Radio Frequency Quadrupole (RFQ) where it bunched and accelerated up to 3 MeV. In the Medium Energy Beam Transport (MEBT) section the transverse and longitudinal beam characteristics are diagnosed and optimized for further acceleration in the Drift-Tube Linac (DTL). The first superconducting section consists of 28 double spoke cavities (SPK) with a geometric beta value of 0.50. The spokes cavities are followed by 60 Medium Beta (MB) cavities with β = 0.67 and 120 High Beta (HB) elliptical cavities, with β = 0.92. After acceleration the beam is transported to the taget through the High Energy Beam Transport (HEBT) section.