One 8 inch (in) and two 6-in Beamports are located on the opposite side of the reactor core from the Fast Neutron Irradiator (FNI). The Beamports provide leakage neutron beams with energies ranging throughout the entire fission spectrum. Physical construction of the Beamports聽consist of an air-filled inner tube positioned between the surface of the reactor and the pool liner. Opposite of the pool liner and within the biological shield is a lead shutter housing, consisting of a 10-in thick lead shutter that shields a majority of the gamma rays from the reactor. This shutter may be raised or lowered for experiments. Positioned after the shutter housing is the shutter housing assembly, which features a feed and drain line to be able to fill or drain the shutter section of the beam tube with water.
The Beamports closest to the Thermal Column terminates at a 2 foot (ft.) x 2 ft. x 2 ft. beam port end box with four conduit lines, built to provide experiment space for larger experiments and instrumentation. The other 6-in Beamport and the 8-in Beamport do not contain this end box, and simply have a beam tube extension that ends at the surface of the biological shield wall. Each beam port also has its own removable plug composed of an aluminum casting filled with ferro-phosphorus concrete and the reactor end tipped with lead. Each plug also contains two 1-in conduit lines for running instrumentation through. Beamports must have at least the plug or shutter in for reactor operations. Fully open beams are not permitted.
The 6-in Beamport closest to the Thermal Column has also been outfitted with a concrete and borated plastic lined bunker. This bunker also has a sample insertion track to allow insertion of samples into the beam tube during reactor operations.
Total Neutron Flux at 1 Megawatt (MW):
- 6 inch Beamport: 4.69E+06 neutrons per centimeter squared per second (n/(cm^2 sec)
Typical Uses:
- Fission spectrum neutron studies
- Sample activation
- Biological studies
Beam Ports During Construction.