The HIBEAM/NNBAR Calorimeter Prototype
The HIBEAM/NNBAR experiment is a free-neutron search for n → sterile n and n → n¯ oscillations planned to be installed at the European Spallation Source under construction in Lund, Sweden. A key component in the experiment is the detector to identify n - n¯ annihilation events, which will produce on average four pions with a final state invariant mass of two nucleons, around 1.9 GeV. The beamline
