Double-differential cross sections for the neutron production from heavy-ion reactions

The systematic measurements of the double differential cross sections for the neutron production have been performed. The beams used in the experiment are C, Ne, Si, Ar, Kr and Xe ions having the incident energy E/A=290-800 MeV. These data will provide important information on the radiation-shielding design of high-energy heavy-ion accelerators. For the measurements with heavier beam such as Xe, it was found that background neutrons produced by interactions of the beam with the air is not negligible. To reduce those background neutrons, a 4 m-long gas bag filled with He was installed. By using the bag, we succeeded to reduce the background significantly. (author)