well....yes....if you have samples from before and after....
But...I prefer we prevent the “after” rather that worry about how to prosecute the guilty.....
Who is the "they" referred to?
If "their" is supposed to refer to "each batch," it is obviously wrong and ambiguous. If a writer cannot use the language in which he writes then his thought processes are probably not very well constructed as he is clumsy in his use of the tools of thought.
http://nuclearweaponarchive.org/Nwfaq/Nfaq6.html#nfaq6.2
It’s a little dry, but it will answer lots of your questions.
Yes generally correct.
The reactor neutron density and general reactor design determines the fission products.
I think there are about 30 different possibilities.
However you need a sample of before and after the reactor and I don’t think Iran or North Korea is going to surrender it.
Plutonium is "cooked" and can be traced to individual reactors, and sometimes to individual batches from the same reactor. U-235, on the other hand, is "refined" someplace other than in nuclear reactors and so cannot be "traced" in the way you describe. The weapons-grade fissionables in the triggers of nuclear weapons are often a mix of plutonium and U-235 to some degree.
Furthermore both undergo radioactive decay, but that of U-235 is measured in geologic time. What really matters is that their radioactive decay produces radioactive elements which have very short half-lives as those things go, and these, in the weapons-grade fissionable triggers of nuclear weapons, sooner or later interfere with the necessary chain reaction for proper detonation of the trigger.
This radioactive decay poisoning of fissionable triggers in nuclear weapons should be distinguished from radioactive decay of the tritium used to "boost" the yield of almost all such weapons, particularly for those involving fusion of some sort.
x-Soviet and Russian fissionable triggers use a much higher proportion of undesirable fissionable elements than Western fissionable triggers, because the Russkis were and are significantly deficient relative to the West in the means of "cooking" and refining their weapons-grade fissionables. This is due to skilled manpower and equipment issues.
As a result, x-Soviet and now Russian nuclear weapons have much shorter storage lives than Western nuclear weapons. Western ones can work after decades in storage if their tritium is periodically topped off. The next biggest storage life issue for Western nukes is oxidation of the chemical explosives used to form the shock wave lenses of their triggers. That can be dealt with, to some extent, by sealing the things in a nitrogen atmosphere inside plastic, but generally the chemical explosives have to be replaced periodically, just not as often as the tritium.
The Soviets, and now the Russians, remove their nuclear warheads from their missiles, or bombs, or whatever, and periodically send them back to the "factory" to have their fissionable triggers "re-cooked", or "re-refined", to get rid of the decay poisonous elements and bring the plutonium and/or U-235 back up to the intended degree of purity. This produces a constant parade of Russian nukes between the launchers and the weapons factories/refineries. Security for the things is a major issue.
Yes, they can sleuth it out. A significant part of intelligence is determining these signatures. Massive efforts are made throughout the entire DoD to do that. Many participating in these efforts don’t even know they are, but the data is collected and analyze. Chemical, biological, and nuclear signatures, materials and sources, and weapon systems are cataloged for future reference by all kinds of analysts, from the State Dept wanting to negotiate arms treaties to defense contractors needing specs on enemy weapon systems.
The nuclear issue are some of the most sensitive because of the types of systems and intelligence required to perform the work of sniffing out nuclear materials and systems. That’s about as far as that conversation can go.