Patent ID: 8437443

Claim:
A method of producing radioisotopes, the method comprising: choosing at least one irradiation target with a known neutron cross-section, the irradiation target not being a neutron detector; inserting the irradiation target into an instrumentation tube of a nuclear reactor, the instrumentation tube extending into the reactor and having an opening accessible from an exterior of the reactor, to expose the irradiation target to neutron flux encountered in the nuclear reactor when operating, the irradiation target substantially converting to a radioisotope when exposed to a neutron flux encountered in the nuclear reactor, the inserting including positioning the irradiation target at an axial position in the instrumentation tube for an amount of time corresponding to an amount of time required to convert the irradiation target to a radioisotope at a flux level corresponding to the axial position based on an axial neutron flux profile of the nuclear reactor; and removing the irradiation target and produced radioisotope from the instrumentation tube.