Extended Data Fig. 5: Energy response of the set-up.
(a) Generated vs. reconstructed energies of the four-neutron system for a uniformly distributed generated energy in the range \(-60 < {{\rm{E}}}_{4{\boldsymbol{n}},{\rm{gen}}} < 100\,{\rm{MeV}},\) transported through the experimental set-up. A clear diagonal correlation between the generated and reconstructed energies is observed. The colour code represents the acceptance of the set-up, normalized such that the maximum corresponds to one. (b) Projection of the acceptance as a function of the generated energy. (c) Projection of the response, as an example, for generated energy of zero MeV. The fitted width of the distribution of 1 MeV corresponds to the resolution of the reconstructed energy
