Muons on my mind
Fukushima Daiichi and the power of muons
A little known particle (unless your particle physicist) called a “muon” is about to be deployed to assist the Japanese assess the damage within the Fukushima Daiichi nuclear plant. The reactor plant has three wrecked cores, hundreds of tons of irradiated materials contributing to dangerous radiation levels, confined spaces and toxic atmospheres. The building is fortified with reinforced concrete that makes the use of X-rays or other scanning technologies impossible. In addition the irradiated material under intense heat melted and has since solidified throughout the complex. It presents a near impossible mitigation challenge. Following the earthquake and tsunami three and half years ago, no one has examined the damage.
Enter the muon.
What is it?
The muon is a fundamental particle that acts like a heavy electron, with a mass about 207 times that of an electron. Muons are unstable and fall apart in 2.2 millionths of a second on average, decaying into electrons, neutrinos and anti-neutrinos.
What is it?
This particle was discovered when physicists were trying to understand the behavior of cosmic radiation. Cosmic radiation is naturally occurring radiation that strikes Earth from space. They were unable to explain the behavior in electrons that penetrated lead while others bounced off. They discovered a new particle that was similar to the electron but had 200 times more mass. They have low energy and high mass and are harmless, several hundred pass through your head every minute. They are so penetrating that most go straight through the planet and zip out the other side at near the speed of light without any effect on their trajectory. Occasionally, a muon will hit an atomic nucleus, and it will change direction in a way that gives a clue about the shape of the target and the target’s density. The technique of detecting those scattered particles and inferring what it was that they bounced off is called muon tomography.
So…
According to articles in the New York Times and Phys.org the Los Alamos National Lab has created a way to use the muon to safely peer inside the cores of the Fukushima Daiichi reactors. Using muon tomography to construct high resolution images of the damaged nuclear materials and breached cores without exposing personnel to harmful radiation doses.
Los Alamos has partnered with Toshiba Corp. to provide plant operators the ability to see the location of the nuclear material inside, determine its condition, and provide crucial insight that can inform the design of a safer and faster cleanup. It is hoped that the time required to clean up the disabled complex will be reduced by at least a decade and greatly reduce radiation exposure to personnel working at the plant.
