One of the big problems with dealing with the aftermath of a nuclear disaster is the fact that it can be hard to know exactly what happened and is happening. After an accident at a nuclear power plant, the building may be heavily irradiated by a breached reactor core. This makes it impossible for human beings to enter the building to investigate. Robots have been constructed and sent into radioactive ruins but the robots tend to break down because of the radiation. There have been attempts to use the flux of particles known as muons to try to locate the melted cores of the Fukushima reactors but these methods are cumbersome. Recently, researchers in the U.K. have come up with a new type of camera that may assist in the examination of locations where dangerous radiation is present.
Conventional detectors for nuclear radiation such as high-intensity neutron and gamma rays are installed inside the reactor core when nuclear power plants are constructed. Unfortunately the conditions are so harsh that even without any sort of accident, the detectors often do not survive for the life of the power plant. Once the detectors are in place and the nuclear reactor is operational, it is difficult to replace them. The reactor must be completely shut down in order to reach the detectors. Serious accidents will usually destroy these conventional detectors.
Malcolm Joyce, a professor of nuclear engineering, and Jonathan Beaumont, a research student, at Lancaster University recently developed a new type of camera based on the way that a cat's eye functions. The Cumbria-based nuclear technology company Createc collaborated in the creation of the new camera.
The camera contains a detector plate behind a collimator (a type of filter) which has a slit shaped hole that is similar to the shape of a cat's pupil. This slit limits the amount of radiation that can hit the detector. The radiation can only reach the detector from one direction as opposed to the case with a standard collimator which allows radiation from all directions to hit a detector. This directionality is essential in pinpointing a source of radiation. With a standard collimator, a detector has to scan all horizontal and vertical positions. With the new camera, the investigators can scan a single line across the general location of the core and figure out where the radiation is hottest.
This new camera weighs about forty four pounds and can fit in a suitcase. It can be easily transported to the location of the reactor and set up to be operated remotely. With one single horizontal scan and a single optional vertical scan, the strongest radiation leaks from the core can be imaged. The development of this camera is a major break-through and will be of great importance in the future when nuclear reactors leak radiation. It will be much easier and cheaper in the future to determine what is happening inside a damaged reactor because of this invention.
An image a functioning reactor core from the cat's eye camera:
