Production of quasi-stellar neutrons by the 7Li(p,n) 7Be reaction has been used for measuring s-process cross sections and efforts to upgrade the proton beam intensity with RF linear accelerators are presently ongoing. We investigated the effect of an energy-broadened proton beam, as is expected for a RF linear accelerator, on the produced 25-keV quasi-Maxwellian neutron spectrum and compared it to that of a Van de Graaff accelerator with well-defined proton energy. Neutron spectrum measurements from 0° to 80° were carried out with a pulsed proton beam at the IRMM Van de Graaff accelerator using time-of-flight techniques, both with a narrow energy spread (σ≈1.5 keV) proton beam and with an energy-broadened beam (σ≈20 keV) obtained by straggling through a Au-foil degrader. In the latter case, the neutron spectrum is closer to the Maxwellian flux distribution in the high neutron energy region.
|Original language||American English|
|Journal||Journal of Physics: Conference Series|
|State||Published - 2012|
|Event||5th Bi-Annual Nuclear Physics in Astrophysics, NPA5 - Eilat, Israel|
Duration: 3 Apr 2011 → 8 Apr 2011