Neutrons and energy

Measurements in neutron physics constitute the major needs from nuclear physics required for the energy problem. There is a large economic payoff for precision in the cross sections needed to optimize the design and operation of power reactors. In particular, there is a pressing need for accurate standards to determine neutron flux at all energies from thermal and 14 MeV. The R matrix formalism has shown that some of the reactions used to measure neutron flux are questionable standards. Since the safety of fast reactors depends to a large extent on doppler broadening of narrow neutron resonances in the keV energy region much more basic research is required on neutron resonances and in particular on multi-level effects. The management of long lived radioactive waste arising from buildup of transuranium isotopes in power reactors requires the measurement of the neutron cross sections of these highly radioactive isotopes. The design of fusion reactors producing 14 MeV neutrons demands detailed knowledge of the interaction of fast neutrons with nuclei in the thermal to 14 MeV energy range