Muon Tomography at LANL

Muon Tomography

On March of 2011, Japan’s Fukushima Daiichi was hit with a magnitude 9 earthquake and a tsunami, which caused the meltdown of three reactors. The meltdown of these reactors released high levels of radiation (higher than the two atomic bombs dropped on Hiroshima and Nagasaki during World War II combined). With the radiation levels lethal within the reactor; a LANL device can lessen human exposure to radiation, showing conditions within the reactor while workers remain outside. Los Alamos scientists have created a new type of penetrating “vision” that can detect nuclear materials, such as uranium and plutonium, hidden inside very thick layers of concrete and steel to find and remove the deadly fuels. This is made possible by Muon Tomography.

Muon tomography utilizes muons, highly penetrative subatomic particles in the lepton family with a makeup similar to an electron, only much more massive, to enable imaging of dense materials. The technique can be used to detect radioactive materials and thus has several nuclear non-proliferation applications. Countless muons constantly shower the earth, and the Los Alamos researchers found that by placing a pair of detectors in front of and behind an object, they could derive a detailed image of the muon scatter. Some materials, including uranium, have a greater scattering effect on the path of muons as they pass through them, so this method could help identify where molten nuclear fuel is located inside the reactors. There are many advantages of muon tomography as opposed to other techniques, muon tomography is non-invasive and does not introduce any additional radiation, and muon tomography is capable of imaging materials covered by thick shielding, where other techniques are not able to penetrate. Additionally, muon tomography can image sensitive items without revealing too much design detail, which is useful for treaty verification. Additional uses to this technology include detecting pathways and chambers inside the pyramids of Egypt and to search beneath active volcanos. Muon radiography pioneered after the 9/11 attacks has also been applied in portal monitoring to detect potential smuggling of nuclear materials. Even heavily shielded contraband can noninvasively be detected without breaching the container.

LANL scientist Christopher Morris interviews about the Fukushima nuclear disaster and how muon tomography can help.

A NOVA episode featuring LANL's muon tomography system.(Around minute 14.)

Two “super modules” comprise a muon detector, demonstrating two-sided imaging using muon radiography.

Muon tomography also has applications unrelated to nuclear non-proliferation. Physicist Elena Guardincerri from LANL group P-25 is utilizing the technique to image a fragile historical landmark, il Duomo in Florence, Italy. The technique can be used to gain a better idea of the structural integrity of the dome without fear of damage.

The famous il Duomo in Florence will be scanned using muon tomography to identify structural weaknesses.