The252Cf(sf) Neutron Spectrum in the 5- to 20-MeV Energy Range

Abstract

The 252Cf neutron spectrum is measured at high energies with a miniature ionization chamber and two different NE-213 neutron detectors. The gamma-ray background and the main cosmic background caused by muons were suppressed by applying efficient pulse-shape discrimination. On the basis of two-dimensional spectroscopy of the neutron time-of-flight and scintillation pulse height, the sliding bias method is used to minimize experimental uncertainties.The experimental data, corrected for several systematic influences, confirm earlier results that show negative deviations from a reference Maxwellian distribution with a 1.42-MeV spectrum “temperature” for neutron energies above 6 MeV.Experimental results of this work are compared with various statistical model approaches to the 252Cf(sf) neutron spectrum.