Based on the success of the currently running program and motivated by new physics needs the NA61/SHINE Collaboration proposes to continue the measurements of hadron and nuclear fragment production properties in reactions induced by
hadron and ion beams after the CERN Long Shutdown 2 (LS2).
These measurements are requested by heavy ion, cosmic ray and neutrino communities and they include:
(i) measurements of charm hadron production in Pb+Pb collisions for heavy ion physics to find out how the onset of deconfinement impacts open charm and J/$\psi$ production.
(ii) measurements of nuclear fragmentation cross section for cosmic ray physics
to study the origin of Galactic cosmic rays and evaluate the cosmic-ray background for signatures of astrophysical dark matter
(iii) measurements of hadron production induced by proton, pion and kaon beams for neutrino physics to improve further the precision of hadron production measurements necessary for initial neutrino flux predictions for the T2K, T2K-II, Hyper-Kamiokande, and DUNE long-baseline neutrino oscillation experiments.
The requested measurements require a substantial detector upgrade which is planned to be executed during the LS2 and the measurements are scheduled in the period 2021-2024.