The accumulator of the ESSNUSB for Neutrino production

The European Spallation Source (ESS) is a research centre based on the world’s most powerful neutron source currently under construction in Lund, Sweden, using 2.0 GeV, 2.86 ms long proton pulses at 14 Hz for the spallation facility (5MW on target). The possibility to pulse the linac at higher frequency to deliver, in parallel with the spallation neutron production, a very intense, cost effective, high performance neutrino beam. The high current in the horns of the target system for the neutrino production requires proton pulses far shorter than the linac pulse. Therefore an accumulator ring is required after the linac to produce the shorter pulses. Charge exchange injection of an H− beam from the linac would be used. The Linac would deliver 1.1 1015 protons per pulse. Due to space charge limits, several rings or one ring re-filled several times during the neutrino cycle are necessary.