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Particle Physics To Aid Nuclear Cleanup
mdsolar sends this report from Symmetry Magazine:
Cosmic rays can help scientists do something no one else can: safely image the interior of the nuclear reactors at the Fukushima Daiichi plant. ... [M]uon tomography is similar to taking an X-ray, only it uses naturally produced muons. These particles don't damage the imaged materials and, because they already stream through everything on Earth, they can be used to image even the most sensitive objects. Better yet, a huge amount of shielding is needed to stop muons from passing through an object, making it nearly impossible to hide from muon tomography. ... By determining how muons scatter as they interact with electrons and nuclei within the item, the team's software creates a three-dimensional picture of what's inside. ... To prove the technology, the Los Alamos team shipped a demo detector system to a small, working nuclear reactor in a Toshiba facility in Kawasaki, Japan. There, they placed one detector on either side of the reactor core. "When we analyzed our data we discovered that in addition to the fuel in the reactor core, they had put a few fuel bundles off to the side that we didn't know about," says Morris. "They were really impressed that not only could we image the core, but that we also found those bundles."
Impressive series of images in the article showing how they get clear data after about four weeks.
Uhhhh... did they just admit to not keeping track of where they've been keeping nuclear fuel rods?
for your tin foil hat
I'm normally pretty mean to particle physicists, but this gear seems pretty nifty. More good info about something is rarely a bad thing.
These particles don't damage the imaged materials and, because they already stream through everything on Earth
That is some bullshit and whoever wrote this summary must be joking.
Muons are produced by high energy collision in the upper atmosphere. Muons (heavy form electrons) can have more than 1 TeV energy. To say "the don't damage anything" is the most retarded statement in the world. They are one of THE principal reasons for cosmic radiation at ground level. If people were transparent, you could detect 1+ muon exploding inside you. And you'd also see a nice trail of ionized flesh along its entire path.
How do I know? I've measured muons in my undergrad physics class. We used a few centimeters of lead to stop them (ones with specific energy rage, of course) and then measure their lifetime.
Fun tidbit - it's one example of Special Relativity that we can detect them at ground level at all.
Anyway, getting back to the damaging bits, they are much more dangerous than any few Bq of Cesium you eat. But hey, "natural radiation" can't be bad! Only the stuff people make must be, right? right? Too bad there is no difference.
I get the feeling there's a superhero origin story somewhere in all this "Let's bombard active nuclear fuel rods with muons and see what happens".
You are welcome on my lawn.
As usual, please do not use Slashdot summaries for your physics education.
You know it's time for the next revolution when your rulers' names end with roman numerals.
And is this normal procedure?
Someone sneaking a bit of plutonium creation?
Just carelessness?
Brains and looks sign me up Los Alamos!
The mouons are created when highly energetic protons and iron nucleii from the solar wind hit our upper atmosphere.
Solar wind is no where even close to strong enough to create muons, as it doesn't even travel at relativistic speed let alone carry couple hundred MeV of energy. The vast majority of cosmic rays come from outside of the solar system, especially when considering the energies need to muons, and 99+% of the cosmic rays are protons.
they come into being traveling at relativisitc velocities. So, for them, a few dozen miliseconds pass before they decay-- but to us, they exist for several dozens of seconds.
The half-life of muons is a couple microseconds, not on the order of milliseconds. And even the highest energy ones we can detect will have lifetimes shorter than dozens of seconds. Since they are traveling close to the speed of light, they can travel over half a kilometer without taking into account time dilation, and for the vast majority of muons this is only extended by a factor of ten to hundred. That is still plenty of distance to reach detectors, but means lifetimes below a millisecond. At the limit of what we can detect, there is barely enough energy to be discussing 10s lifetimes, with fluxes many orders of magnitude below typical.
Long enough for them to come streaming down from the sky in an endless daylight barrage of partical radiation.
Practically the same number of muons come at night as during the day... there is some diurnal variation due to the effects of the Sun's magnetic field on lower energy cosmic rays, but since the cosmic rays are not coming from the Sun, they are almost always present with only small variations.
Mouons that come into being from fission decay reactions arent quite as energetic-- but still useful for imaging purposes.
Not only are fission decays not energetically likely to produce muons, they can't funnel that into pair production and don't involve the weak force in the right way to produce a single muon. You're not going to be detecting them from fission decays with such a setup.
Transporting said fuel rods by air exposes them to shittons of them.
Anything, whether in a building, or underwater or in lead will be exposed to a lot of muons, unless behind kilometers of material.
Createc (http://www.createc.co.uk) has been deploying a system called "N-Visage" at Fukushima Daiichi to image the insides of the reactor halls.