Moderator and beam port assembly for neutron radiography
US4599515A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 20, 1984 |
| Grant date | Jul 8, 1986 |
| Priority date | — |
| Expiry date | Jan 20, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG21K1/00
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A moderator and beam port assembly is designed particularly for use with an accelerator source of fast neutrons to provide a collimated beam of thermal neutrons directed toward an object position for neutron radiography. A central moderator of solid hydrogenous material, preferably high density polyethlene, having a high hydrogen density and substantially no neutron poisons, has a source cavity lying on the beam axis for supporting the source of fast neutrons adjacent the axis. To form a beam of thermal neutrons, a ring of neutron poison material is disposed outside the moderator to form an aperture symmetrically disposed about the axis. The moderator has an inner beam port cavity extending substantially symmetrically of the axis from the aperture substantially to the source cavity. A heavy metal shield just outside the poison ring stops gamma rays produced upon capture of neutrons by the moderator and ring material. The shielding has a diverging opening mating the aperture with the entrance to a divergent beam collimator symmetrically disposed about the axis. The collimator is formed of heavy metal and neutron poison. The assembly is housed in a container substantially filled with…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.