ESSnuSB: a Project for Leptonic CP Violation Discovery based on the European Spallation Source Linac

Very intense neutrino beams and large neutrino detectors will be needed in order to discover of CP violation in the leptonic sector. The proton driver of the European Spallation Source (ESS) currently under construction in Lund, Sweden, could provide, in parallel with the spallation neutron production, a very intense, cost effective and high performance neutrino beam. The ESS linac will be fully operational at 5 MW average power by 2022. The proposal presented here is to upgrade the linac to give another 5 MW to produce neutrinos i.e. 10 MW average power, in total. The high current required in the pulsed neutrino horn, requires proton pulses compressed from 2.86 ms to a few μ s in an accumulator ring. A long baseline experiment using this Super Beam and a megaton underground Water Cherenkov detector located in existing mines 300–600 km from Lund, will enable precision measurements at the second νμ→νe neutrino oscillation maximum and thereby discover leptonic CP violation at 5 σ significance level in more than 50% of the leptonic Dirac CP-violating phase range. The detector would also be used to measure the proton lifetime, detect cosmological neutrinos and neutrinos from supernova explosions. The presentation will describe the proposed facility and the physics possible with this experiment.