The European Spallation Source neutrino Super Beam project and physics performance

The goal of the ESSnuSB project is to precisely measure neutrino Charge-Parity Violation (CPV). The construction of the European Spallation Source, ESS, represents an outstanding opportunity for such project to take place. ESSnuSB has been funded from EU in the framework of H2020 (2018-2022) and Horizon Europe (2023-2026) to make feasibility studies. The aim of the first phase was to demonstrate that the ESS linac can be used to generate an intense neutrino beam, which coupled with a megaton water Cherenkov detector placed in a mine 360 km from ESS, could allow the detection of neutrinos at the 2nd oscillation maximum. A CDR* has been published in which it is shown the unprecedented physics performance to precisely measure CPV. For this, the modification to compress the proton pulse length from 2.86 ms to 1.3 μs has been studied. The second, ongoing Design Study, ESSnuSB+, is devoted to neutrino cross-section measurements relevant to ESSnuSB. Two facilities are proposed, a low energy nuSTORM (muons decaying to neutrinos in a storage ring) and a low energy ENUBET (pions decaying to a muon and a neutrino and monitoring of the neutrino beam by detection of the decay muon).