Cross Section Measurements of (n,x) Reactions In the Energy Range Between 16.4 and 18.9 MeV Using Highly Enriched Ge Isotopes

Abstract

In this work, the cross sections of the neutron induced reactions ⁷⁰Ge(n,2n)⁶⁹Ge, ⁷⁶Ge(n,2n)⁷⁵Ge, ⁷³Ge(n,p)⁷³Ga, ⁷²Ge(n,p)⁷²Ga, ⁷³Ge(n,d/np)⁷²Ga, ⁷⁴Ge(n,d/np)⁷³Ga, ⁷⁴Ge(n,α)^71mZn, ⁷²Ge(n,α)^69mZn, ⁷³Ge(n,nα)^69mZn have been measured in the energy range between 16.4 and 18.9 MeV via the activation technique with respect to the ²⁷Al(n,α)²⁴Na reference reaction. Most of the existing experimental datasets found in literature for these reactions, were obtained with the use of a ^natGe target. In this case however, the residual nucleus produced from some reaction channels, could also be produced from neutron induced reactions in neighboring isotopes that exist in the ^natGe in their natural abundance, acting as a contamination to the measured yield of the reaction of interest. This parasitic contribution should then be subtracted, based on theoretical calculations that bear their own uncertainties. Isotopically enriched targets on the other hand, do not suffer from such contaminations, leading to more accurate experimental cross section results. In this work, five highly enriched targets have been used that helped in the determination of accurate cross section data, especially in the case of the⁷³Ge(n,d/np)⁷²Ga, ⁷⁴Ge(n,d/np)⁷³Ga and ⁷³Ge(n,nα)^69mZn challenging reactions, that will be presented in detail in this manuscript. The experiments were carried out at the 5.5 MV Tandem Van de Graaff accelerator of N.C.S.R. “Demokritos”, implementing the ³H(d,n)⁴He reaction for the production of the quasi-monoenergetic neutron beams.