Synopsis: Peeking into Fukushima’s Reactors

Cosmic rays may be used to capture images of damaged reactors at the Fukushima power plant in Japan.

Workers at Fukushima Daiichi power plant have come up with creative ideas to assess the conditions of the reactors damaged in the 2011 nuclear accident, sending balloons and robots to explore the highly radioactive environment. Yet the presence of debris, obstructions, and vapors has limited the effectiveness of such explorations. Writing in Physical Review Letters, Konstantin Borozdin at the Los Alamos National Laboratory, New Mexico, and colleagues propose an alternative method that uses cosmic-ray muons, a part of natural background radiation, to obtain a radiographic image of the reactor cores.

Cosmic rays are charged particles, mostly protons, coming from outer space and hitting the Earth at high speeds. Colliding with molecules in the atmosphere, they generate a shower of other particles. These include muons, sort of heavier versions of electrons that, if sufficiently fast, can penetrate many meters into materials. This property first enabled an intriguing imaging application in 1969, when a team led by Luis Alvarez used muon radiography to search for hidden chambers in the Egyptian pyramids of Giza.

To radiograph inaccessible parts of Fukushima reactors, Borozdin et al. propose a similar approach based on muon detectors placed right outside the reactor building. The authors compared two imaging methods: attenuation radiography, which measures how muons are absorbed inside the reactor, and scattering radiography, which monitors how their path is deviated. They show that scattering radiography would deliver more reliable images of the nuclear core after only a few weeks of measurement, allowing the visualization of melted fuel as well as debris.

While their sources remain to a large extent a mystery, cosmic rays might help us decipher one of our own human misfortunes. – Matteo Rini


Features

More Features »

Announcements

More Announcements »

Subject Areas

Nuclear PhysicsInterdisciplinary Physics

Previous Synopsis

Astrophysics

New Shape to Nuclear Pasta

Read More »

Next Synopsis

Semiconductor Physics

Finding Ferroelectrics

Read More »

Related Articles

Synopsis: Intel on Stellar Element Production from Accelerator Data
Nuclear Physics

Synopsis: Intel on Stellar Element Production from Accelerator Data

Measurements of a nuclear reaction relevant to the synthesis of calcium, potassium, and argon in stars boost the accuracy of models for predicting the elements’ abundances. Read More »

Viewpoint: Heaviest Element Has Unusual Shell Structure
Nuclear Physics

Viewpoint: Heaviest Element Has Unusual Shell Structure

Calculations of the structure in oganesson—the element with the highest atomic number—reveal a uniform, gas-like distribution of its electrons and nucleons. Read More »

Focus: <i>Video</i>—Nuclear Fusion in Hi-Def
Nuclear Physics

Focus: Video—Nuclear Fusion in Hi-Def

A new model provides a detailed visualization of the clustering of protons and neutrons within the excited nuclear compound formed just after two nuclei collide and fuse. Read More »

More Articles