Albright Attempts to Deflect Neutron Activation Issue at Parchin

On May 15, I pointed out that the claims associated with the cartoon published by George Jahn of AP purporting to depict a high explosives chamber used by Iran at Parchin (this is a new link for the cartoon, the AP link in the May 15 post no longer works for me) and in a report by David Albright claiming that Iran has taken actions aimed at cleansing the Parchin site were rendered baseless by the likelihood that if the accused work on a neutron initiator for a nuclear weapon had indeed been carried out at Parchin, then the chamber would be rendered radioactive throughout the thickness of its steel by the process of neutron activation. Yesterday, Albright published even more photos of the Parchin site that he claims document further cleansing activity and in the discussion section of his report he finally addressed the issue of neutron activation. In order to make the issue of neutron activation go away, Albright is now proposing that  the uranium deuteride presumed to be present in the explosion would produce too low a flux of neutrons to produce appreciable neutron activation of the chamber’s steel, even though Jahn is claiming that the Iranians placed a neutron detector outside the chamber, presumably to measure the neutron flux that passed through its steel walls.

Here is the relevant portion of a 2009 report by Albright describing the neutron initiator:

If the data in this document are correct and the descriptions of the work are accurate, then this report appears to be describing a plan to further develop and test a critical component of a nuclear weapon, specifically a neutron initiator made out of uranium deuteride (UD3), which when finished (and subsequently manufactured) would most likely be placed at the center of a fission bomb made from weapon-grade uranium. This type of initiator works by the high explosives compressing the nuclear core and the initiator, producing a spurt of neutrons as a result of fusion in D-D reactions. The neutrons flood the core of weapon-grade uranium and initiate the chain reaction.

Albright goes on to describe the issue of producing neutrons and measuring their production:

The measurement of the neutrons emitted by this UD3 source would be the hardest measurement Iran would need to make in developing a nuclear weapon. This assumes that Iran believes it cannot do a full-scale nuclear test, although it would be expected to do a “cold test” of the full device as a way to gain confidence the nuclear weapon would perform as expected. . . The timing of the explosion and resulting shock waves would need to be perfect in order to get enough fusion to create a spurt of neutrons in a reliable manner at exactly the right instant. The experiment itself is very difficult to do. There are relatively few neutrons emitted in a brief period of time and there is a lot of noise from the electronics that interferes with the neutron measurements.

It should be noted here that although Albright is discussing a “cold test”, that means the test is carried out without the weapons grade uranium which the initiator sets off in the nuclear explosion. The uranium deuteride is still present as the primary part of the initiator and is producing the neutrons which are to be measured. Although Albright does claim that few neutrons are produced in the explosion in the latter part of the description, he refers to a “spurt” of neutrons that “flood” the weapons grade uranium in the earlier portion. The fact remains that in such an experiment, significant quantities of uranium are present and there would be neutrons released into the steel of the chamber the entire time the uranium is present, not just during the brief explosion.

As further support for the uranium deuteride initiator being the primary focus of the narrative promoted by Albright and Jahn, it should be kept in mind that Jahn mentions that the chamber is “equipped with” “a neutron detection system outside the explosion chamber to measure neutron emissions”. Jahn goes on to quote another expert who posits the use of uranium in the experiments with explosives:

Diplomats subsequently told the AP that the experiments also appear to have involved a small prototype neutron device used to spark a nuclear explosion – equipment that would be tested only if a country was trying to develop atomic weapons.


“What one does inside such a chamber is conduct high explosives testing,” said Mark Fitzpatrick, director of the Non-Proliferation and Disarmament Program of the International Institute for Strategic Studies. “You are going to make something go boom with maybe 70 kilograms (more than 150 pounds) of high explosives, you need to contain the explosion.

“And particularly if you are using uranium, which is reportedly the case, you want to contain all the uranium dust so there’s not any tell-tale, observable signals of that experimentation.”

In his report yesterday, Albright suddenly came up with a German publication which he cites as evidence that the neutron flux from the explosives experiments would be too low to produce significant neutron activation. Don’t be distracted by the presence of tungsten being used as a surrogate material. It is not a surrogate for the uranium deuteride initiator, it is a surrogate for the weapons grade uranium that would be present in a bomb. That means this is the “cold test” described in Albright’s earlier work:

Some have raised the possibility that, if the explosive chamber had been used to test a neutron initiator, this type of test would leave behind a radioactive signature in the steel.  According to Süddeutsche Zeitung (article in German language), the chamber could have been used to test a uranium deuteride initiator at the center of a sphere of tungsten used as a surrogate material, all of which would have been compressed by high explosives. If successful, the resulting fusion of deuterium would have produced a small spurt of neutrons. In this case, a tiny fraction of these neutrons would have activated elements in the steel chamber.  This has led to the question whether the induced radiation could now be detected by the IAEA. However, in such a neutron initiator test, the number of neutrons is very small and many of the activated materials would have had relatively short half-lives.

Albright’s argument that “many” of the nuclides produced by neutron activation are short-lived is meaningless here, as I have pointed out that the primary evidence that IAEA could find if such experiments were indeed carried out would be Cobalt 60, which has a half-life of over five years.

However, even Albright does not seem entirely convinced by his own argument here, as he immediately moves on to how Iran could otherwise deal with neutron activation in the chamber due to the Cobalt 60 present:

Although long lived radionuclides should have been produced in such a test, they would exist in very small quantities.  Claims that such radioactive materials would be easily detectable today appear doubtful. Moreover, the detection of minute amounts of long-lived radionuclides in the steel chamber may not provide definitive proof of an initiator test. Iran could claim that the steel was already contaminated when it purchased it. In addition, Iran could have removed the chamber altogether, preventing any risk of such detection, even if it were possible to accomplish.

The issue of “contaminated” steel presumably could be addressed by sampling other steel items manufactured by the company that is said to have produced the chamber, since Jahn provides the name of the company said to have made the chamber. In fact, Jahn even provides an approximate production date, so other steel produced by this company around the same time could be sought out for testing.

Finally, however, Albright gets to the conclusion I have been stating all along. If Iran really did carry out uranium deuteride initiator work in the chamber, their best bet for hiding the neutron activation evidence would be to remove the chamber in its entirety.

In a very interesting development somewhat tied to the concept of “removing” the chamber in which the accused work may have been carried out, Gareth Porter published a report yesterday in which he calls into question the very existence of a chamber.

15 replies
  1. Starbuck says:

    I did a little research on neutron initiator and the references pointed to D-T initiators (Deuterium-Tritium) initiators, producing neutrons at 14.1MeV, well above the energies produced by UD3. Now this (D-T) material is the preferred method for making initiators and at 14+MeV, unless the steel was really, really think, the neutrons would be detected, if the scintillator and electronics were robust enough to stand the shock.

    So it looks to me that Iran is at the level of the experiments at Los Alamos in the 40’s, which is crude indeed. Or else we are being flummoxed with this report.

  2. Kathleen says:

    Leveretts have an important one up
    “America’s policy on Iran-related secondary sanctions is on a collision course with itself as well as China. Secondary sanctions violate the United States’ obligations under the World Trade Organization and are, thus, illegal. (While a WTO signatory may decide, on national security grounds, to restrict its trade with another country, there is no legal basis for one state to impose sanctions against another over business that the second state conducts with a third country.) If Washington actually imposed secondary sanctions on another state for, say, buying Iranian oil and the sanctioned country took the United States to the WTO’s Dispute Resolution Mechanism, the United States would almost certainly lose the case.

    Given this reality, the whole edifice of Iran-related secondary sanctions is in reality a house of cards. It rests on an assumption that no state will ever really challenge the legitimacy of America’s Iran-related extraterritorial sanctions—and this means that the United States cannot ever really impose them. Instead, successive U.S. administrations have used the threat of such sanctions to elicit modifications of other countries’ commercial relations with the Islamic Republic; when these administrations finally reach the limit of their capacity to leverage other countries’ decision-making regarding Iran, the United States backs off.

    The Obama Administration is bringing this glaring contradiction increasingly to the fore, by supinely collaborating with the Congress to enact secondary sanctions into laws that give the executive branch less and less discretion over their actual application. This dynamic is now coming to a head in the Administration’s dealings with China.”

  3. Jim White says:

    @Starbuck: I’m wondering if the bit about “a lot of noise from the electronics that interferes with the neutron measurements” there is both, as you suggest, the problem of the electronics surviving any pressure wave that might be outside the chamber and also a relatively high background of neutrons due to the presence of the UD3 in the first place. Does the blast only marginally increase and redirect the neutron flux that is already there from the uranium? And would that be enough on its own to give a detectable level of activation in the tank?

  4. Cheryl Rofer says:

    What Might the Iranians Have Tested at Parchin?

    There are at least three possibilities related to weapons. And now that the Iranians have been mucking around with the site, there is no way that anyone will ever believe that negative findings by the IAEA mean anything.

    I also address the question of neutron activation. Short version: hard to say without doing some calculations.

    Nuclear Diner is up and running again. We’ve replaced most of what we’ve lost in the hack and are adding new material daily.

  5. Jim White says:

    @Cheryl Rofer: Thanks for the link to that informative post. Your reasoning makes a lot of sense. I lean toward thinking activation would be observable if UD3 experiments were carried out, but, as you say, more quantitative information is needed for a firm conclusion. [And congratulations on getting the site back up and running, that must have been quite a pain to go through.]

    The polonium stuff and Arafat caught my eye, too. The quick calculation I did said that what they found on the underwear, if we allow for decay, was about 5 ng. That would fit as a reasonable residue to find if he was given a dose similar to what many believe was given to Litvenko, in the neighborhood of tens of micrograms.

  6. Cheryl Rofer says:

    @Jim White: I haven’t done any calculations relative to the Arafat question, but don’t forget that a large number of half-lives need to be factored in.

  7. P J Evans says:

    It sounds like Albright and Jahn are trying to have their pre-written story and make it work with the real-world evidence, and failing badly.

    (The only time I’ve actually met uranium was in physics, in the form of pitchblende – and we handled it with tongs. It’s crumbly as well as thoroughly radioactive.)

  8. Starbuck says:

    Neutron detection isn’t easy (or wasn’t when I instrumented experiments on neutron measurements)because it has no charge. but that was too many years ago. Nonetheless, I brought it up for consideration anyway.

    What is the detector material of choice to make the measurements? We used BF3 back then (which probably really dates me…ok it was about 1957, at Argonne National Labs).

    Since leaving there, I became more interested in QP so I didn’t follow advances at the nuclear level. Whatever I did read never commented on neutron measurements, therefore this piqued my interest.

  9. JohnLopresti says:

    There are what sound like low energy tools common in several kinds of earth exploration which utilize a neutron source. I heard one discussion in which such simple and common instruments could fit into an experiment such as the one which may have been conducted at Parchin. In grape growing low energy neutron beam based tools were coming into use for soil studies pre-planting 30 years ago. The Parchin tests evidently at issue took place more recently than that, about 10-15 years ago.

  10. orionATL says:

    i don’t think albright is dealing with science anymore qua science.

    he is operating in the realms of propaganda and cover-your-big-bare-ass-cause-it’s-showing. “science” in this instance is useful for obfuscation and evasion of charges of being an untrustworthy source, not for achieving understanding. once the excuse of “too low a level to be detected” has been invoked, then from there on out it’s “he said, she said”.

  11. JohnLopresti says:

    @Starbuck: Any idea whether the NM Lab measured neutral pion energetics? Pion research was fairly robust in the decades of the 50s-60s, although colliders were producing particles with substantially more mass than a neutral pion 135 MeV and at greater energies, given the beam sources.

    Also, I remain mystic about the neutrino variations that have appeared in the new physics. I do not know whether Nasa plans neutrino work during its next gen asteroid based research, either.

    What I have considered is utilizing space platforms to look into the earth’s atmosphere for light particle events. I know NM remained quite interested in cosmic ray showers, too, during those years.

  12. Starbuck says:


    NM? Are you referring to Los Alamos? I worked at Argonne in Illinois.

    So far as I remember, and in any case, the energy levels were far below 125MeV, no pion research was happening. We were about 2.5MeV, off a Van De Graff Linac.

    Fermilab is doing major neutrino research with it’s long baseline experiment (LBNE) which runs from Batavia Il to Lead Colorado utilizing the old Homestakes mine at about 5000 to 7000′ below sea level.

    That is, if funding isn’t pulled:

  13. JohnLopresti says:

    @Starbuck: Thanx. My hasty mistake about NM, of course. Fermi had a pretty good bubble chamber in those early years, as well. I will look at the link; I knew of the South Dakota Pb mine work unspecifically; it’s design looks interesting and its folklore colorful; I have done some work for the former Homestake elsewhere. Additionaly, there is the quite different work in a Zn mine on Mt. Ikenoyama the so-called Kamiokande. I do not know why I thought of possible asteroid use in a similar way. My concept was realtime observation of earth places like iaea sites of interest. But the energetics are likely a laughable misconception. The discussion I mentioned was by some people who know what the available technology is.

    Still, neutrinos might fit the muse. They’re so elusive…

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