# US 8,542,789 B2 · Irradiation target positioning devices and methods of using the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,542,789 B2 - Document ID: US8542789B2 - Status: Granted - Kind: B2 - Application number: 12/718,260 - Filed: 2010-03-05 - Published: 2011-09-08 - Granted: 2013-09-24 - Earliest claimed: 2010-03-05 - Assignees: GE-Hitachi Nuclear Energy Americas LLC - Applicants: William Earl Russell, II; Heather J. Hatton; Melissa Allen; Melissa L. Hladik; Samuel John Lafountain; Luis Alberto Torres; Erick W. Dittmer - Inventors: William Earl Russell, II; Heather J. Hatton; Melissa Allen; Melissa L. Hladik; Samuel John Lafountain; Luis Alberto Torres; Erick W. Dittmer - Web page: https://patentgrep.com/patent/US8542789B2 ## CPC - G21G 1/00: Arrangements for converting chemical elements by electromagnetic radiation, corpuscular radiation or particle bombardment, e.g. producing radioactive isotopes (separation of different isotopes of the same element B01D59/00) - G21G 1/02: in nuclear reactors (by thermonuclear reactions G21B; conversion of nuclear fuel G21C) - G21G 1/06: by neutron irradiation - H05H 6/00: Targets for producing nuclear reactions (supports for targets or objects to be irradiated G21K5/08 {; preparation of tritium C01B4/00; targets, e.g. pellets for fusion reactions by laser or charged particles beam injection H05H1/22}) - G21G: CONVERSION OF CHEMICAL ELEMENTS; RADIOACTIVE SOURCES (applications of radiation in general G21H5/00; handling particles, e.g. neutrons, or electromagnetic radiation not otherwise provided for G21K) - H05H: PLASMA TECHNIQUE (apparatus or processes specially adapted for producing X-rays H05G2/00); PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS ## Abstract Example embodiments and methods are directed to irradiation target positioning devices and systems that are configurable to permit accurate irradiation of irradiation targets and accurate production of daughter products, including isotopes and radioisotopes, therefrom. These include irradiation target plates having precise loading positions for irradiation targets, where the targets may be maintained in a radiation field. These further include a target plate holder for retaining and positioning the target plates and irradiation targets therein in the radiation field. Example embodiments include materials with known absorption cross-sections for the radiation field to further permit precise, desired levels of exposure in the irradiation targets. Example methods configure irradiation target retention systems to provide for desired amounts of irradiation and daughter product production. ## Claims ### Claim 1 A method of providing an irradiation target positioning system, the method comprising: determining an irradiation target and a daughter product produced from the irradiation target; determining physical characteristics of a radiation field to which the irradiation target will be exposed; configuring the irradiation target, an irradiation target plate, and a target plate holder to produce the daughter product when the irradiation target is loaded in the irradiation target plate and the target plate holder in the radiation field; and determining a quantity and a location of the irradiation target relative to a center of the irradiation target plate such that the quantity and the location of the irradiation target varies based on the physical characteristics of the radiation field. ### Claim 2 (depends on 1) The method of claim 1, further comprising: loading the irradiation target into the irradiation target plate and the target plate holder; and irradiating the irradiation target loaded in the irradiation target plate and the target plate holder in the radiation field so as to produce the daughter product. ### Claim 3 (depends on 2) The method of claim 2, wherein the radiation field is a neutron flux including thermal neutrons produced in a light-water reactor. ### Claim 4 (depends on 2) The method of claim 2, wherein the configuring includes providing at least one of, a shape, size, and known absorption cross-section for the irradiation target, a constant position of the irradiation target in the radiation field to be maintained by the irradiation target plate and the target plate holder, and materials for the irradiation target plate and the plate holder with known absorption cross-sections for the radiation field. ### Claim 5 (depends on 1) The method of claim 1, wherein the physical characteristics of the radiation field include at least one of radiation type and radiation energy distribution over position. ### Claim 6 (depends on 1) The method of claim 1, wherein the irradiation target is fabricated from a material including at least one of cobalt (Co), chromium (Cr), copper (Cu), erbium (Er), germanium (Ge), gold (Au), holmium (Ho), iridium (Ir), lutetium (Lu), molybdenum (Mo), palladium (Pd), samarium (Sm), thulium (Tm), ytterbium (Yb), and yttrium (Y). ### Claim 7 (depends on 1) The method of claim 1, wherein the configuring includes providing at least one loading position in the target plate for the irradiation target. ### Claim 8 (depends on 7) The method of claim 7, wherein the configuring further includes defining a hole in the target plate at each loading position, the hole configured to retain the irradiation target in the target plate. ### Claim 9 (depends on 8) The method of claim 8, wherein the configuring further includes placing at least one target spacing element in the hole so as to maintain the irradiation target at a constant position within the loading position. ### Claim 10 (depends on 8) The method of claim 8, wherein the configuring further includes placing at least one spacer plate in the target plate holder so as to maintain the target plate and at least one loading position at the constant position within the radiation field. ### Claim 11 (depends on 10) The method of claim 10, wherein the at least one spacer plate is placed adjacent to the target plate in the target plate holder so as to retain the irradiation target at the constant position. ### Claim 12 (depends on 1) The method of claim 1, wherein the configuring includes providing the irradiation target plate with a first planar surface and an opposing second planar surface, a distance between the first and second planar surfaces being less than a diameter or length of the irradiation target plate. ### Claim 13 (depends on 1) The method of claim 1, wherein the configuring includes providing the irradiation target plate with an opening extending through the center and a plurality of holes surrounding the opening, the opening being larger than each of the plurality of holes. ### Claim 14 (depends on 13) The method of claim 13, wherein the configuring includes inserting the target plate holder through the opening of the irradiation target plate.