On the accuracy of cross-section measurements of neutron-induced reactions using the activation technique with natural targets: The case of Ge at En=17.9 MeV

Several cross-section measurements of neutron-induced reactions on Ge found in literature, are performed utilizing Ge-nat targets. The production of the same residual nucleus as the measured one might occur as a result of the unavoidable presence of neighboring isotopes in the same target, acting as a contamination. Corrections must be made based on theoretical calculations and models in order to resolve this problem. The accuracy and limits of a methodology for these ''theoretical corrections'' are investigated in this work using isotopically enriched targets, which can produce very accurate results without the need for such corrections. Experimental cross-section measurements have been made for the Ge-76(n,2n)Ge-75, Ge-72(n,alpha)Zn-69m and Ge-72(n,p)Ga-72 reactions, via the activation technique, with the Al-27(n,alpha)Na-24 reaction used as reference, employing both a Ge-nat and isotopically enriched Ge targets. The H-3(d,n)He-4 (D-T) reaction was used for producing the quasi-monoenergetic neutron beam in the 5.5 MV Tandem Accelerator Laboratory of the National Centre for Scientific Research ''Demokritos'' in Athens, Greece, at an incident deuteron beam energy of 2.9 MeV. Using HPGe detectors, gamma-ray spectroscopy was applied to determine the induced gamma-ray activity of the residual nuclei.

Automated summary

This study investigated the accuracy and limitations of theoretical corrections in neutron-induced reactions on isotopically enriched Ge targets. Experimental cross-section measurements were conducted on several reactions using Ge-nat and isotopically enriched Ge targets. The results showed that the methodology using isotopically enriched targets provided accurate results without the need for theoretical corrections.