Fission and other fast neutron induced reactions investigated at nELBE

The nELBE neutron time-of-flight facility provides neutrons in the energy range from about 10 keV up to 10 MeV with an intensity of about 10⁴ n/s/cm². The combination of the superconducting electron accelerator ELBE and a compact liquid lead neutron production target delivers neutron bunches within a time spread of a few picoseconds and a repetition rate of 100 to 400 kHz (cw) enabling high resolution time-of-flight measurement even with flight paths of only 5 to 11 meters. At nELBE different types of fast neutron induced nuclear reactions can be and have been investigated, ranging from total neutron cross section measurement over elastic and inelastic scattering to neutron induced fission. E.g. the neutron induced fission cross section of Pu-242 has been measured in the range from 0.5 to 10 MeV relative to U-235(n,fis) using two fission ionization chambers. A statistical uncertainty down to 1.1 % and systematic uncertainty of about 2.7 % was reached.