The Np-237(n,f) cross section at the CERN n-TOF facility

Abstract

The Np-237(n,f) cross sections have been measured at the n-TOF facility relative to the U-235 and U-238 fission cross sections. The n-TOF spallation neutron source at CERN is characterized by a high intensity flux, an excellent time resolution and an extensive neutron energy range (from eV to GeV). A fast ionization chamber was used as a fission fragment detector with efficiency better than 97%. Preliminary Np-237(n,f) cross sections have been deduced in the energy range from 20 keV to 10 MeV and are found in good agreement with data from literature.