| Popis: |
In the case of proton‐irradiated radioisotope production, niobium target capsules containing gallium are exposed to intense radiation, thermally induced stress, for extended periods. The structural integrity of the target capsules is of crucial importance for containing the accelerator‐produced radioisotopes and target material. The capsule window should be as thin and transparent to the proton beam as possible, and preferably should not become significantly activated under proton irradiation. In addition, the material for the capsule needs to be as defect‐free as possible. Niobium encapsulated gallium targets have a history of unpredictable failure under intense irradiation with 100 MeV protons. This study illustrates the utility of non‐destructive testing in order to detect defects that may result in mechanical failure of the capsules during irradiation. Prior to this work, it was not known if the gallium initially wets the niobium capsule that encapsulates it, and if it does, it is not known to what de... |
