(Mining.com) – Gold foil was utilized to help researchers work out if the Idaho National Laboratory’s (INL) NRAD neutron beam still meets national standards after its nuclear reactor obtained upgrades, Joe Campbell of INL reports.
“We wanted to make sure we still met ASTM’s Category I standard after the core upgrade, but we realized that other researchers wishing to conduct examinations here would find a precise map of the beam’s intensity very useful. Testing with an array of gold foil targets was the best way to do that,” said INL postdoc researcher Aaron Craft.
Gold is the best material for the job because of its short half-life and “how it reacts to exposure to the neutron flux in a reactor.”
“Gold as it is found in nature—gold-197—contains no finds of its radioactive isotopes. But, when exposed to a neutron beam, a little percentage of a given experiment of gold will turn to gold-198, which has a half-life of 2.7 days.”
Craft clarified “The percentage of gold-198 created is directly proportional to the intensity of the neutron beam that hits each sample in the array. Utilizing the half-life of 2.7 days for gold-198, and the facts and figures from the experiment enumerations finished in MFC’s Analytical Lab, I then have everything I need to conceive an accurate chart of NRAD’s beam intensity,” also added “Such a chart can help attract other researchers who need to analyze or check samples after exposure to a neutron flux that agrees NRAD’s profile.”