Developing a Radiochemical Method to Measure Thermonuclear Detector Cross Sections

Kenton Moody | 19-FS-020


We demonstrated two methods of producing and purifying carrier-free 88 Y for introduction into National Ignition Facility (NIF) capsules as a target for nuclear cross section measurements. Both methods rely on producing 83-day 88 Zr and allowing it to decay to 106-day 88 Y to reduce unwanted mass introduced by impurities in reagents and production targets. The first method involved the irradiation of Sr with alpha particles, which has a relatively low production rate but has potential advantages in purification chemistry. The second method involved the irradiation of Y with protons, which has a much larger production rate but requires stringent chemical purification to remove the target matrix.

Impact on Mission

Our research leveraged Lawrence Livermore National Laboratory's core competencies in nuclear, chemical, and isotopic science and technology and supports the development of nuclear science measurements at the Laboratory's NIF. Our results provide the basis for preparing materials used in measurements of nuclear data in a plasma environment, which will in turn positively impact the uncertainties and interpretation of radiochemical data obtained in historic nuclear tests. Therefore, our work advances the Laboratory's stockpile stewardship mission area with first-principles understanding of fundamental science that will advance experimental platforms and diagnostic capabilities in the focus area of high-energy-density science.