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New Neutron Scatter Camera to Detect Smuggled Nukes
Researchers at Sandia National Laboratories in California are developing a new neutron scatter camera that they claim will be able to detect radiation through much more shielding and at much greater distances than traditional tech. "The neutron scatter camera consists of elements containing proton-rich liquid scintillators in two planes. As neutrons travel through the scintillator, they bounce off protons like billiard balls. This is where "scatter" comes into play -- with interactions in each plane of detector elements, the instrument can determine the direction of the radioactive source from which the neutron came. [...] Computers record data from the neutron scatter camera, and using kinematics, determine the energy of the incoming neutron and its direction. Pulse shape discrimination is employed to distinguish between neutrons and gamma rays."
This is part of the problem with working under government contracts on projects and interests that are ultimately unrelated - you always have to justify the research. I worked in this department at Sandia for a few summers, and that was generally the opinion I heard. Everyone there is interested in fusion research to provide cheap power to the world, but they have to do this research under the auspices of supporting national security or nuclear stockpile stewardship. Everyone working there knows that that's not the actual reason for the research, but it keeps the funds flowing in.
1. DoD contractor produces a prototype, then obtains a $100M grant from the DoD to pursue it further.
2. DoD contractor requests $50M for additional research and receives it
3. DoD contractor delivers the detector as a proprietary black box, running Windows, at a price of $10M each. 50 units are ordered by the government.
4. 5 CalTech students make a working detector for $20'000 out of an old scintillation counter, plumbing pipe, and a PentiumIII machine running BSD.
5. Nobody cares.
It is funny how much of the federally funded research right now appears to be directly applied to counter-terrorism efforts. I am all for that being done, but from what I have noticed when going through the national labs web-pages, it seems that the majority of research dollars are going to these efforts. I think that if you counted military research labs, you might find that more federal dollars are going to counter-terrorism than are going to alternative energy projects.
To clarify, this neutron camera is nice for nukes, but what they're actually using the technology for is to examine neutron emissions from fusion capsules compressed with their z-pinch machine.
A local nuclear physicist in our area recently commented about the current detection systems in use. He regarded them as so easily thwarted they are basically worthless. He even described how to do it on a local news broadcast (sorry, I couldn't find a link). It basically involved very low cost (common) materials. He indicated the type of technology talked about in this article is really the only meaningful method for detecting nuclear material. He further stated that the organizations responsible for detecting this material know what they are using is worthless, but are unwilling to spend the additional money needed for the correct technology. He was upset that they were more interested in putting on a 'show' of force, rather than offering real protection.
Let's hope that isn't true, and places like Sandia are working on making nuetron detection less expensive.
How long? let's see. if they're "developing" it now, say 3 years until it's in production and another year until it's at the major points of entry. But you've got to cover all the points of entry - sea, air(freight), land via Canada and Mexico. Make that about 10,000 PoE in all, so you're talking about another couple of years at least. That means about 6 years or until the beginning of 2014 to get a few grapefruit sized pieces of metal across the border.
Really bad thought: maybe it would be easier to get material that's already in US stockpiles - what use are border checks then?
politicians are like babies' nappies: they should both be changed regularly and for the same reasons
No, the range of these neutrons is pretty short. If unshielded and unscattered - a few hundreds of yards in free air. Or, in practice, a few tens of feet at best. I think you are confusing neutrons (which can be shielded against, but the shielding is heavy) with neutrinos (which go through everything).
Yes, this is true. This is not however an argument against these machines - as no defense will cover all bases.
Okay, let's see here...strokes kill about 150000 people each year in the U.S., and the government spends about $400 million on stroke research. Terrorists with radioactive materials have killed approximately zero people ever, and the government spends $650 million+ on (admittedly clever) directional radiation detectors. Yeah, we're clearly doing a great job of rationally allocating our money.
You fail to understand statistics. The 150k strokes a year is a large statistical sample and thus it is easy to predict the number from one year to the nect with some degree of statistical accuracy.
Now consider the nuclear case. There have been zero incidents since nuclear weapons existed in man-portable form, say 20 years ago. Now assuming a poisson distribution of events this means that we can conclude with a 95% confidence level that the rate of such events is less than 3.09 per 20 years i.e. less that a roughly 15.4% probability per year. Assuming that such an event would kill 1 million people this means that we are only 95% certain that the annual death rate from such terrorism is less than the death rate from strokes.
However the above is a conservative estimate because technology is making it easier to build nuclear weapons so whereas the above calculation assumed a constant probability distribution of such events that is not correct and it is getting more and more probable. So really we are less than 95% certain. In addition comparing the death rate is not a fair statistic. A better comparison would be years of human life lost. A majority, but certainly not all, stroke victims are old or have recently suffered other life threatening conditions like a heart attack or aneurism. However a terrorist bomb would kill children as much as the elderly (and everyone in between).
So while you cannot show that this is the most effective way of spending money to save life neither can you show that it is not. However given the uncertainties in any such calculation it is far from a total waste of time which is what you were suggesting.