Fast neutrons from thick helium target irradiated by 17 MeV deuterons

The spectral yield of fast neutrons from the d + He (thick target) reaction has been measured at different angles for the incident deuteron energy of 17 MeV. The measurement has been performed in an open geometry employing th e shadow-bar method. The scintillation detection technique with two-dimensi onal n-gamma discrimination electronics has been used. In the measurement, the list mode of the PC data-acquisition system was effectively employed in the elimination of the parasitic neutron contribution, caused by the rando m fluctuation of the beam-spot position out of the target window. The measured angular distribution of the neutron yield was compared with re levant data of the reaction Be(d, xn). The high yield, Gaussian-like shape of the energy spectrum and strongly forward-directed emission of neutrons f rom the thick He target seem to be advantageous for selected irradiation ta sks. (C) 2001 Elsevier Science B.V. All rights reserved.