Measurement of the MACS of ¹⁸¹Ta(n,γ) at kT=30 keV as a test of a method for Maxwellian neutron spectra generation

Measurement of the Maxwellian-Averaged Cross-Section (MACS) of the reaction at kT=30 keV by the activation technique using an innovative method for the generation of Maxwellian neutron spectra is presented. The method is based on the shaping of the proton beam to produce a desired neutron spectrum using the ⁷Li(p,n) reaction as a neutron source. The characterization of neutron spectra has been performed by combining measured proton distributions, an analytical description of the differential neutron yield in angle and energy of the ⁷Li(p,n) reaction, and with Monte Carlo simulations of the neutron transport. A measured value equal to 815±73 mbarn is reported for the MACS of the reaction at kT=30 keV. The MACS of the reaction provided by KADoNiS has been used as a reference.