Geant4 simulation of the n_TOF-EAR2 neutron beam: Characteristics and prospects

The characteristics of the neutron beam at the new n_TOF-EAR2 facility have been simulated with the Geant4 code with the aim of providing useful data for both the analysis and planning of the upcoming measurements. The spatial and energy distributions of the neutrons, the resolution function and the in-beam $ \gamma$ -ray background have been studied in detail and their implications in the forthcoming experiments have been discussed. The results confirm that, with this new short (18.5m flight path) beam line, reaching an instantaneous neutron flux beyond 10$^{5}$n/μs/pulse in the keV region, n_TOF is one of the few facilities where challenging measurements can be performed, involving in particular short-lived radioisotopes.