Title: Damaged Fukushima nuclear material could be imaged
Date: Oct. 17, 2012 at 7:44 PM
U.S. researchers say cosmic rays could be used to gather detailed information from inside the damaged cores of the Fukushima Daiichi nuclear reactors
The process is similar to the way X-ray images are produced
“We now have a concept by which the Japanese can gather crucial data about what is going on inside their damaged reactor cores [...],” Konstantin Borozdin of Los Alamos’ Subatomic Physics Group said.
Cosmic Ray Radiography of the Damaged Cores of the Fukushima Reactors
Konstantin Borozdin, Steven Greene, Zarija Lukic, Edward Milner, Haruo Miyadera, Christopher Morris
Accepted to Physical Review Letters
September 12, 2012
Two muon-imaging methods that use flux attenuation and multiple Coulomb scattering of cosmic-ray muons are being studied as tools for diagnosing the damaged cores of the Fukushima reactors.
The model of the reactor included all major structures, the reactor building, containment vessel and the pressure vessel. Calculations were performed for an intact core, a core with a 1 m diameter of material removed from the core and placed in the bottom of the pressure vessel, and with no core.
At one hour the difference in scattering between the images with and without the core is visible and by ten hours the reactor core is visible in the scattering image. At 4 days the 1 m diameter void is visible in the core, and by 6 weeks both the void and the resulting sphere of core material the below the core are clearly visible.
We have shown that 6 weeks (300 m^2 weeks of exposure) of data provide an image with enough quality to observed 1% (a 1 m diameter sphere) of core material moved to a location below the core using scattering radiography. [...] high quality data for radiography of the Fukushima cores from outside of the buildings can be accomplished with scattering radiography and large detectors. On site tests at Fukushima Daiichi have shown these measurements to be practical.
Published: October 18th, 2012 at 12:12 am ET