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This should have been in Camera

Dear Reader,

The recklessness of some people drives me to a new level of distraction, I have chosen to not name the case or the newspaper in this blog article but I will tell you the story. Some irksome pest tries to build a homemade bomb, this homemade special fails. Then the news paper reports the court case explaining how and why it failed to detonate.

What I think is that any public discussion of a failed bomb is an educational moment which we are better off without. The problem I see is that building any complex gadget is hard when you have to make everything yourself. Having had an interest in electronics I can tell you that many gadgets have taken a lot of development work to get to the level which the public now considers “normal”.

Also having been in the business of developing chemical processes, I can tell you that the creation of a process (or even just the implementation of an existing process)  can take a lot of work. One of the things which always makes it more easy is a knowledge of how someone else did it successfully and an understanding of what went wrong the last time.

The knowledge that a particular method or material is unsuitable for a task is a great help, it saves a lot of time and effort. The reason is that a person will not go chasing after something which does not work. By publishing a truthful discussion of how a bomber failed the newspapers are helping the next generation of bombers by improving their knowledge.

Some years ago I was told something interesting at the ITU in Germany, they commented that a large fraction of illicit plutonium samples which have been intercepted contain red materials. They believe that the Soviet intelligence services leaked some misinformation about “red mercury”. The story is that “red mercury” greatly increases the ease of building a working nuclear weapon.

By releasing this crazy story about a spoof material, the Soviets were attempting to  waste the time and efforts of would-be nuclear terrorists. By encouraging them to chase a false lead it would have helped world peace. The reason is that every hour and dollar a terrorist spends looking for ways to obtain and use this material is a hour or dollar which they could not use one something which is more likely to provide them with a weapon. Very clever I think !

I have to ask why the facts of this type of case be discussed in public, and why the newspaper staff did not have the sense not to self censor what they published.

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Trinitite

Dear Reader,

Recently I purchased off eBay a small lump of trinitite, now I had been warned that a lot of fake trinitite is being offered for sale. So I choose to take the step of examining the sample with gamma ray spectroscopy.

In less than a minute I had been a peak at 668 keV which could either be due to either 214Bi (665 keV from the beta branch) or 137Cs (662 keV from 137mBa) was seen. This peak suggested that some radioactivity was present in the sample. I did a quick check at 609 keV. The line at 665 is emitted during a small fraction (1.46) of beta decays of 214Bi, while the 609 keV photons are emitted by 46.1 of all decays. As a result it is clear that the sample contains some man made radioactivity.

trinitite1a

Next I looked at the low energy end of the spectrum, here is a log log view to allow you to see this part of the spectrum better. I found a strong peak at 66 keV. I suspect that this is 59.5 keV peak for americium, keep in mind that the energy calibration of the detector is a little off. It was over reporting the energy of the 137mBa, so it is not totally unreasonable for it to over report the energy of the 241Am. As americium is associated with plutonium this is a good sign that the rock is a true lump of trinitite.

trinitite2

I then looked for some of the other lines of this americum nuclide, I looked for 99 and 103 keV photons. I found peaks at 99, 101 and 105 keV. This suggests that some peaks were in this expected range. Maybe it could be americium present. At 81 keV we should expect a peak for 133Ba, in our spectrum we see peaks at 81.7, 83.8 and 87.7 keV.

Also at 128 keV the spectrum contains a peak which could be due to the 122 keV line from 152Eu.

trinitite3

The spectrum also contains at 1414 keV a line which could be due to the 1408 keV emission from 152Eu. Also this nuclide will emit at 964, 444 and 245 keV. In the high energy part of the spectrum we can also see a line at 1466 keV which corresponds to the 1461 keV emission of 40K (decaying into 40Ar).

trinitite5

In our spectrum we see a line at 969 keV which can be matched with the 964 keV emission of 152Eu.

trinitite6

We can go further into the problem, in the range of 400 to 500 keV it is hard to decide if a peak is present. The signal to noise ratio is too bad in this range.

trinitite7

Now if we try again in the range of 200 to 300 keV range, we can see a line at 251 keV which is a possible match to the 245 keV.

trinitite8

The section of the spectrum between 300 and 400 keV shows peaks at 358 and 362 keV one of which could be the 356 keV line for 133Ba.

trinitite4

I think that after seeing this evidence that we can come to the conclusion that the rock sample came from a place where a nuclear fission event occurred, so it is likely to be real trinitite.

We will come back to this later, what I hope to do next is to try to estimate the way in which the efficiency of the detector changes as a function of photon energy. We will try to match the different lines from different radionuclides to the graph.

The greenpace bomb / pod

Dear Reader,

Greenpeace have become upset that the Russians complained that they took an object near a oil / gas site which looked like a bomb. Greenpeace say it is a harmless “pod” which is a cylinder three meters long and two meters in diameter. Greenpeace say it is clearly not a bomb as it is painted in “bright colours”.

The problem is that evil minded bomb makers tend to devise new ways to make their bombs look harmless, for example Ted Kaczynski (Unabomber) made a bomb which looked like a plank of wood.

I am aware of a case in Europe where someone threw a harmless looking object (a snowball) over the fence of a nuclear site. I have visited this nuclear site quite a few times in the course of my professional life, the guards there are a strict but reasonable group of men. The guards impose strict rules but they are a decent bunch of men, I have always found them to be polite and friendly group of men.

However I know that they have an important job to do, they are responsible for preventing unauthorised people entering a site where bomb useable materials are present, they also have the task of preventing the unauthorised movement of nuclear materials in or out of the site.

The problem was that some silly person thought it would be funny to throw a snowball over the fence of the site, at this site all bags and other objects which you take in or out have to be inspected. I am not allowed to carry any cameras, guns, radioactive objects etc etc in or out of the site.

When the snowball went flying over the fence the armed guards quite rightly acted, they went and arrested the snowball thrower. While it might be a harmless object, the problem is that until the snowball is found and examined then it is impossible to know what has come flying over the fence. The problem I see is that the snowball is white and will break up on impact, the ground is covered with white snow. Thus finding the snowball remains will not be easy.

I hold the view that if the person who had thrown the snowball had gone a short distance from the site, or into the woods near the site then they could have had the biggest snow ball fight of history and the guards would not have cared at all, neither would I care about a bunch of youngsters having a snowball fight as long as it occurred at a sensible distance from the site.

In the same way, I am sure that nobody in the oil / gas industry would care less about the “pod” if Greenpeace had taken it somewhere else into the middle of nowhere. The fact that this object was being taken to an illegal protest site makes it an object which the oil / gas platform owners and operators should view as suspect. I also note that Greenpeace are using their pods to try to defeat the security measures being used to prevent unauthorised people boarding ships and oil rigs.

To my mind the pod is being used like an armored lid on a siege engine from ye olde days, while Greenpeace and some others might not like what they think is an overreaction by the Russians (They think their harmless looking pod should be trusted by all people as being eco friendly and harmless) I think that Greenpeace should be ashamed for playing such a stupid card. While after close inspection the pod will be found to be a harmless irritation, quite rightly it should be treated as a suspect object until it is shown to be harmless.

I would also like to ask the reader to consider for a moment what would (and what should) occur if while the Queen is walking around seeing people if you jump over the barrier and run towards her with a bag filled with chocolates and boiled sweets (for her to enjoy later). I suspect that if you are lucky you will just be arrested, while if you are unlucky you will be beaten to the ground or maybe even worse. If any of my readers feel the overwhelming urge to give either Queen Elizabeth the second (of the UK) or the King of Sweden a nice big box of chocolates and other nice things I strongly suggest you contact the office of the head of state some weeks in advance and ask how best the gift should be delivered by some mutually agreeable method.

Even if Greenpeace had been trying to deliver packets of sweets, bottles of gin lemonade, cigarettes heathy snack bars and other gifts to the oil / gas field workers in their pod then they would have had provoked a similar response. I say shame on Greenpeace for playing the “its only a harmless ‘pod’ card”.

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