Absolute cross-sections for some (n, p), (n, α) and (n, 2n) reactions

Quantitative Analysis of Mg, Na, Cl, Al, and Ca in Human Dental Calculus by Neutron Activation Analysis and High Resolution Gamma-Spectrometry

“…In this investigation this was ignored for several reasons. In the determination of Na, the interference caused by the reaction 27A1 (n, a) 24Na can be ignored because of the low concentration of Al compared with that of Na in dental calculus and because the fast neutron cross section of Al is much lower than the thermal neutron cross section of Na.2' The interference of the 24Mg (n, p) 24Na reaction also can be ignored because the thermal neutron cross section of Na is much higher than the fast neutron cross section of Mg. 22 In the determination of Mg, interference caused by the reaction 27A1 (n, p) 27Mg can be neglected because of the low concentration of Al compared with that of Mg in dental calculus. In addition, Calvi, Potenza, and Vinciguerra23 determined the fast neutron cross section of Al for reactions (n, p) and found it to be low.…”

Neutron Detection and Spectroscopy With Semiconductor Detectors

“…At the beginning of the project two techniques for neutronenergy measurement were considered. These were the Li 6 -sandwich spectrometer and a stacked-detector absorber array. The bulk of the effort in the project was devoted to the development of the Li&-sandwich detector and associated electronic system.…”

“…Solution evaporation is preferable when a thick coating of B 10 or if 35 is desired for maximum sensitivity. Vacuum exaporation is preferable when very thin uniform films of Li 6 and Li 6 F are required on the detector surface. A thermal neutron source was usedto observe the response of each coating material deposited on the detectors as a function of dead layer and radiator thickness.…”

“…Solution evaporation is preferable when a thick coating of B 10 or U 336 is desired for maximum sensitivity. Vacuum evaporation is preferable when very thin uniform films of Li 6 and Li 6 F are required on the detector surface. The highest sensitivity oo thermal neutrons is obtained with a thick coating of B 10 , because of its high cross section and large number of atoms per unit weight as compared to U 335 .…”

“…This was consistent with the anticipated neutron spectrum emitted from the self-replenishing deuterium target. Because of a number of uncertainties in the Li 6 spectrometer adjustment, this result should be considered preliminary. An effort to observe lU-MeV neutrons was unsuccessful because of the high background counting rate from competing reactions.…”