I smell an agenda piece. Who are these "Center for Nonproliferation Studies" exactly? Is that even a real subject? What do they know about photographic imaging, which is all about radiation, or any other industrial process? Who are they that scientists should beg their permission to work?
The only really interesting thing about this is the claim that it was weapons grade uranium. I wonder if they mean the same thing other people do when they say that (for me, 90+% U-235), or if the mention of californium means it was blended?
«A steady stream of neutrons is needed for these purposes. Kodak used small research reactors, including one at Cornell University, and possessed a dollop of californium-252, a radioactive isotope that endlessly sheds neutrons.
But it wanted a more potent in-house system, so in 1974 it acquired a californium neutron flux multiplier, known as a CFX. Small plates of highly enriched uranium multiplied the neutron flow from a tiny californium core.»
Weapons grade HEU is typically 80% or above, though strictly speaking anything above about 20% is pretty easy to make a nuke out of provided you have enough material.
Also, back in the day it was quite normal for such small research reactors to use HEU (specifically, about 93% enrichment), and such reactors were pretty commonplace at the time. See: http://en.wikipedia.org/wiki/Research_reactor
There's only on the order of 1 mg of Cf-252 in the source (my estimate) -- enough for the order of 10^9 neutrons/second. It's not a meaningful amount of fissile material. By weapons-grade they mean the uranium in the neutron multiplier is >90% U-235.
NCSU has a currently-operating PULSTAR reactor on campus. I walk by the building multiple times per day when classes are in session. http://www.ne.ncsu.edu/nrp/index.html
One of these days, I need to see if I can get inside and take a look around.
Kodak would have had huge hooks into the national security side of things in the US government.
They made all kinds of films used for imaging various parts of the spectrum, and would have had their researchers available for the USG (surely at a price of course). That they had fissionable material is entirely reasonable and expected.
Having grown up in Rochester with many friends and family who were Kodak employees, I thought I'd ask around. My father, a software developer at Kodak who wouldn't have had any particular reason to deal with the reactor, says he was well aware of it and that it wasn't any big secret.
Given that they filed plenty of public paperwork and notified all the relavent authorities, I'm inclined to agree.
But "Kodak ran a registered nuclear device everybody knew about and that was dismantled years ago" does not nearly sound as catchy as something about a "secret nuclear reactor in an underground bunker"!
Small research reactors are not uncommon at large companies and universities. Even Reed college has one, which I visited last year when I was traveling through Portland. "Tested" recently visited it too
Such reactors were typically fueled with HEU (Reed exchanged their HEU fuel for LEU only a few years ago).
And no reactor is secret -- all civilian reactors in the United States are registered with the NRC and you can look them up on the NRC website (and wikipedia).
Gizmodo may have degraded the story, but the original source (local paper) wasn't much better. I'm afraid it's just another hack story about fission by a hack journalist who couldn't be bothered to do the most basic web search on what he was reporting.
This isn't technically a nuclear reactor (not critical), so it doesn't appear on any of the usual lists like [1] or [2] (prior to edits made after this story came out). It isn't mentioned on any major NRC page, although they host some of its paperwork [3].
* It's a subcritical (K_eff = 0.99) neutron multiplier using 1.5 kg highly-enriched (93%) uranium. K_eff = 0.99 means each fission event triggers a cascade of ~100 more fission events before the activity ceases. In a critical reactor (K_eff = 1) the chain reaction doesn't stop, it perpetuates itself
* The primary neutron source is californium-252, a radioactive isotope which emits neutrons when it decays (by spontaneous fission)
* Highly-enriched uranium is the neutron multiplier (operating as a subcritical reactor). For each neutron in, you get ~100 fissions and ~240 fission neutrons, of which <140 are excess (not absorbed by the uranium itself)
* Runs at about 6 watts => 4 * 10^11 neutrons/second created
1. This isn't a nuclear reactor, technically -- it's a neutron multiplier. The total amount of fissile material is sub-critical, so it can't sustain fission.
2. If you Google "Californium Neutron Flux Multiplier", you can find links to, among other things, the front page of a Kodak-published paper that talks about the use and acquisition of this source. It sounds like it was obtained through a pilot program with the DoE, looking for alternative uses of their nuclear technology. There's also a link to a letter from Kodak's head of radiation safety to the NRC talking about the shut-down and decommissioning of the multiplier.
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[ 3.0 ms ] story [ 71.9 ms ] threadThe source is much cleaner than the submitted site. After reading both articles I feel that the submission is just a rip-off.
Edit: I didn't go deep enough down the rabbit hole. Thanks eli & falling.
Pretty sure that is both the original source and the most accurate write up.
http://www.democratandchronicle.com/article/20120511/NEWS01/...
and it's a better article too.
http://mnrc.ucdavis.edu/about.html
«A steady stream of neutrons is needed for these purposes. Kodak used small research reactors, including one at Cornell University, and possessed a dollop of californium-252, a radioactive isotope that endlessly sheds neutrons.
But it wanted a more potent in-house system, so in 1974 it acquired a californium neutron flux multiplier, known as a CFX. Small plates of highly enriched uranium multiplied the neutron flow from a tiny californium core.»
Also, back in the day it was quite normal for such small research reactors to use HEU (specifically, about 93% enrichment), and such reactors were pretty commonplace at the time. See: http://en.wikipedia.org/wiki/Research_reactor
Cf-252: http://www.nndc.bnl.gov/chart/reCenter.jsp?z=98&n=154
http://reactor.arl.arizona.edu/facilities-mainmenu-32/25-nuc...
It was just decommissioned:
http://azstarnet.com/news/local/education/college/it-s-offic...
One of these days, I need to see if I can get inside and take a look around.
They made all kinds of films used for imaging various parts of the spectrum, and would have had their researchers available for the USG (surely at a price of course). That they had fissionable material is entirely reasonable and expected.
Given that they filed plenty of public paperwork and notified all the relavent authorities, I'm inclined to agree.
http://www.tested.com/videos/44278-will-and-norm-visit-the-r...
Such reactors were typically fueled with HEU (Reed exchanged their HEU fuel for LEU only a few years ago).
And no reactor is secret -- all civilian reactors in the United States are registered with the NRC and you can look them up on the NRC website (and wikipedia).
Gizmodo may have degraded the story, but the original source (local paper) wasn't much better. I'm afraid it's just another hack story about fission by a hack journalist who couldn't be bothered to do the most basic web search on what he was reporting.
[1] http://nucleus.iaea.org/RRDB/RR/ReactorSearch.aspx
[2] https://en.wikipedia.org/w/index.php?title=List_of_nuclear_r...
[3] https://www.google.com/?hl=en#q=kodak+site:nrc.gov+-filetype...
http://www.democratandchronicle.com/article/20120511/NEWS01/...
http://www.democratandchronicle.com/assets/pdf/A2189208511.p...
http://www.democratandchronicle.com/assets/pdf/A2189207511.p...
some stuff:
* It's a subcritical (K_eff = 0.99) neutron multiplier using 1.5 kg highly-enriched (93%) uranium. K_eff = 0.99 means each fission event triggers a cascade of ~100 more fission events before the activity ceases. In a critical reactor (K_eff = 1) the chain reaction doesn't stop, it perpetuates itself
* The primary neutron source is californium-252, a radioactive isotope which emits neutrons when it decays (by spontaneous fission)
* Highly-enriched uranium is the neutron multiplier (operating as a subcritical reactor). For each neutron in, you get ~100 fissions and ~240 fission neutrons, of which <140 are excess (not absorbed by the uranium itself)
* Runs at about 6 watts => 4 * 10^11 neutrons/second created
* 0.33 Curies of spent "fuel" remain
1. This isn't a nuclear reactor, technically -- it's a neutron multiplier. The total amount of fissile material is sub-critical, so it can't sustain fission.
2. If you Google "Californium Neutron Flux Multiplier", you can find links to, among other things, the front page of a Kodak-published paper that talks about the use and acquisition of this source. It sounds like it was obtained through a pilot program with the DoE, looking for alternative uses of their nuclear technology. There's also a link to a letter from Kodak's head of radiation safety to the NRC talking about the shut-down and decommissioning of the multiplier.