how weird are the electronics actually used in nuclear weapons?

[coppercone2]

how do you know the modern bombs don't try to do fine pulse control to try to match the electric detonators/control the plasma (and we really don't know what they choose to use, slapper, bridgewire or other)?

They might also run some kind of tests on the individual detonators (because the above would probably require a giant shed of insane equipment) and electrically match their timing rather then try to choose parts, maybe there is even some kind of a predetonation scan done to adjust the timings to account for explosives properties drift ETC. Or with the new bunker busters and shit they might have to scan the explosives some how to account for any deformation in the plastics due to the high g-forces to redesign the compression wave geometry.

All the above is probably too far out and its probably really bootleg.

[dmills]

The civilian exploding foil stuff uses flexi PCB for the transmission lines to get the low Z required, I would not be that surprised to see something similar.

I have seen an interesting civilian hydrogen spark gap triggered by UV light from an external arc tube, seemed likely to be low jitter if you mounted a few around a suitable pulsed UV source.

Fact is it was difficult in 1950, but I would bet if you actually looked at the requirements for that design (which nobody would design today) the timing is probably not all that tough by modern standards.
Now a modern weapon with variable yield, electrically fired neutron source (Possibly timed to provide that variable yield) and sophisticated PAL, that might be tricky.

Regards, Dan.

[coppercone2]

how many pages can this thread get to before we disappear?

[T3sl4co1l]

Nothing that's been discussed here hasn't been declassified for decades.

Tim

[coppercone2]

Nothing that's been discussed here hasn't been declassified for decades.

Tim

i was hoping a bit of gangster pep would lead to independent discovery 

[LaserSteve]

Oh, it led to my finding one blog on potential ways of  making Alternative Materials  without huge plants and resources of only a small  nation that I do not wish to link.  Trade off sophistication and yield  for time and making a core is simpler.

Steve

[CatalinaWOW]

Modern times and electronic controls, ultra precise machining and a number of other technologies have made fabrication of unique devices far easier than it once was.  Add that to the option to do something over a decade or two instead of the three or four years that it took the first time around doesn't make it easier to sleep at night for those who worry about such things.

On the other hand the same technology growth has made it far easier to detect such attempts.  For example, in my stash of goodies I have a Cutie Pie.  It is one of the top secret radiation detectors used during the initial bomb development, given a silly code name to hide its purpose.  By today's standards its sensitivity and other metrics are laughable.  At best. 

So far at least the publicly available evidence says that the good guys are at least staying even in this race.

[jmelson]

is there actually plausible evidence to a false flag attack? I saw this occur in the movie Phantom.

Just look up K-129 on Wikipedia, and follow some of the links.  There seem to be a lot of people who know something about this.
The Soviets apparently sunk one of our subs in retaliation, believing we sunk the K-129.  Exactly why the sub sank is not totally clear, but the evidence is that a missile was launched and self-destructed as it was coming out of the launch tube.

Jon

[dmills]

Yep, and people always forget about the other fissionables, U and Pu are NOT the only things that could work if you do the sums.

I am somewhat surprised that Am241 is not more of an issue, you could wrap a reflector around a surprisingly small mass and get criticality by my back of an envelope, cannot be bothered to do the sums to see if it would work for a bomb, but a reactor looks workable to me.

I also wonder about (but again cannot be bothered to do the sums) a reactor using a two stage process, start with neutron bombardment of something that will capture the neutron and start a decay chain emitting a few alphas, then bombard beryllium with the alphas to make neutrons.... Probably tricky to get the losses low enough for criticality, but maybe, just maybe.

I wonder if there is something that can be hit with a neutron to get you to one of the Astatine isotopes, that would get you 3 alphas in the decay chain within a few minutes.

Hum, turns out that Bismuth can capture an alpha getting you onto the polonium chain, which would then give you two spare alphas from its decay chain, thats fun if the energies work out, not exactly what I had in mind, but interesting none the less!

Regards, Dan.

[coppercone2]

Modern times have made electronic controls, ultra precise machining and a number of other technologies have made fabrication of unique devices far easier than it once was.  Add that to the option to do something over a decade or two instead of the three or four years that it took the first time around doesn't make it easier to sleep at night for those who worry about such things.

On the other hand the same technology growth has made it far easier to detect such attempts.  For example, in my stash of goodies I have a Cutie Pie.  It is one of the top secret radiation detectors used during the initial bomb development, given a silly code name to hide its purpose.  By today's standards its sensitivity and other metrics are laughable.  At best. 

So far at least the publicly available evidence says that the good guys are at least staying even in this race.

is that still classified or can you share it?

[Housedad]

Nothing that's been discussed here hasn't been declassified for decades.

Tim

Absolutely.
No one that knows classified info, even very old info would be stupid enough to put it on the net, much less even talk in private about it.  Some things stay classified almost forever.   Those that know that kind of info also know how to keep the mouth closed.

[Housedad]

Modern times have made electronic controls, ultra precise machining and a number of other technologies have made fabrication of unique devices far easier than it once was.  Add that to the option to do something over a decade or two instead of the three or four years that it took the first time around doesn't make it easier to sleep at night for those who worry about such things.

On the other hand the same technology growth has made it far easier to detect such attempts.  For example, in my stash of goodies I have a Cutie Pie.  It is one of the top secret radiation detectors used during the initial bomb development, given a silly code name to hide its purpose.  By today's standards its sensitivity and other metrics are laughable.  At best. 

So far at least the publicly available evidence says that the good guys are at least staying even in this race.

Some Tech is used forever.  Even in the face of massive tech advances.

[GeoffreyF]

Try to buy a Krytron with fast enough switching speeds so that shaped charges all go off with the necessary precision to compress the fissionable material.  How fast?  Faster than what you can buy.

If you do try - make sure you have a really good defense attorney.

I can't tell you more. I would have to kill you if I did.

[jmelson]

Yep, and people always forget about the other fissionables, U and Pu are NOT the only things that could work if you do the sums.

I am somewhat surprised that Am241 is not more of an issue, you could wrap a reflector around a surprisingly small mass and get criticality by my back of an envelope, cannot be bothered to do the sums to see if it would work for a bomb, but a reactor looks workable to me.

Well, you have to have something that has a long half life, has a good neutron capture cross-section, neutron capture results in prompt fission, and that fission releases several neutrons.  U235 works, but only releases 2.x neutrons, so it takes a fair amount to achieve a critical mass.
Pu239 is better, as it releases 3.x neutrons, so you need less atoms for a critical mass.

I'm not so sure anything else meets ALL these criteria.

Jon

[CatalinaWOW]

Modern times have made electronic controls, ultra precise machining and a number of other technologies have made fabrication of unique devices far easier than it once was.  Add that to the option to do something over a decade or two instead of the three or four years that it took the first time around doesn't make it easier to sleep at night for those who worry about such things.

On the other hand the same technology growth has made it far easier to detect such attempts.  For example, in my stash of goodies I have a Cutie Pie.  It is one of the top secret radiation detectors used during the initial bomb development, given a silly code name to hide its purpose.  By today's standards its sensitivity and other metrics are laughable.  At best. 

So far at least the publicly available evidence says that the good guys are at least staying even in this race.

is that still classified or can you share it?

It isn't classified now, and AFAIK hasn't been since shortly after WWII.  They were available in open catalogs by 1950.  I don't have time to take a picture of mine at the moment, but if you google with the search term "cutie pie radiation detector" you should get enough information to satisfy your curiosity.  The Star Trek pictures are of a newer model, and they were obsolete enough by the Star Trek era to be used as movie props.  It is also interesting to google with just "cutie pie".  It will show you why that was such a clever cover name.  Talk about burying in a pile.

[jmelson]

is that still classified or can you share it?

Los Alamos National Lab is the home of a lot of weapons-related research, but it is ALSO the home of a bunch of agencies essentially doing the opposite.  There is the Defense Threat Reduction Agency, quietly doing a lot of non-proliferation work in the background.  In 1963, the US launched the first Vela satellites, designed to monitor for space, and later, open-air nuclear tests, to verify compliance with the test ban treaty.
Los Alamos has continued to update these systems.  They apparently also detect rocket and missile launches worldwide.

The current stuff is certainly classified, but the basic existence of the program has been pretty well-known for decades.

Jon

[jmelson]

is that still classified or can you share it?

As for radiation detectors, you can buy quite decent Geiger counter units on eBay!  This was big stuff right after the Fukushima accident.

Jon

[coppercone2]

I was asking specifically about the cutie pie. Keep in mind it got classified because it was literally mind boggling for them at that point, no one knew how fast these weapons would develop and some people even thought they could ignite the atmosphere for a while. I never heard that name before.

[Lord of nothing]

ABC News (Australia) ->

[jmelson]

I was asking specifically about the cutie pie. Keep in mind it got classified because it was literally mind boggling for them at that point, no one knew how fast these weapons would develop and some people even thought they could ignite the atmosphere for a while. I never heard that name before.

Certainly, the Cutie Pie is no longer classified.  It was made by Nuclear Chicago back in the 1950's, and used at least one vacuum tube.
Much better ionization chamber devices have been made since, none of these are classified, you can buy new, certified and calibrated (yes, really expensive) from a variety of manufacturers like Victoreen, Canberra, Ortec, etc.  for a couple thousand $, or not-so calibrated ones on eBay for under $100.

Geiger counters detect Gamma radiation, and if they have a thin window, can also detect Alpha and Beta.  They are very real sensitive.

Ionization chambers are much more sensitive to Alpha and Beta.

Scintillators have much higher efficiency for detecting Gamma radiation.

Jon

[dmills]

I'm not so sure anything else meets ALL these criteria.

For a bomb, possibly not (I think Am242 would but that is harder to make then weapons grade isotopically pure Pu).

However for a reactor delayed neutrons are actually a good thing, you want a reasonable space between delayed and prompt critical (Nobody likes an accidental prompt criticality, it decreases property values).

Regards, Dan.

[schmitt trigger]

Back to the original OP:

In 1961's Goldsboro nuclear near-accident, a simple switch which would have armed the bomb, fortunately remained in the "Safe" position.

That lowly switch prevented what would have been the world's largest nuclear mishap, as all other arming mechanisms had successfully completed the arming sequence.

[jmelson]

No one that knows classified info, even very old info would be stupid enough to put it on the net, much less even talk in private about it.  Some things stay classified almost forever.   Those that know that kind of info also know how to keep the mouth closed.

Well, they are not SUPPOSED to.  10-15 years ago, the entire technical manual of the Hellfire missile was online!  It had detailed description of the arming mechanism, which told you how far away from the launch you needed to be for the warhead to go off, among other details that you really would NOT what your adversary to know about!  Some months later, that manual was gone, thankfully!

In the nuclear area, the same thing has happened, and it was reported in the press, some decades ago, that a whole bunch of stuff that was highly classified ended up getting sent out to university and maybe even public libraries.  They had to send people out to find those documents and retrieve them.

Jon

[coppercone2]

yea but that stuff is probobly ultra compartmentalized in different special access programs specifically so you can't have a document fuckup cause a security problem.

I am sure there is ultra basic classified shit that we would think like hurr durr when we saw it but they know that if you research it you will be inclined to do it some other way thats conceptually better and the hurr durr method that works great might take a while to realize for whatever reason etc.

lol i want to find that manual though it sounds like a fun read. something to leave near the toilet seat perhaps for bored guests? reminder not to shit on the floor like a drunken baffoon (like the fly drawings they put in urinals)

[GeoffreyF]

Nobody has caught the bit about Krytron's or - sprytron's?  This was about electronics.  That actually is the crucial electronic thing.   If you ever saw a picture of the trinity test, did you sort of wonder why the wires to the slapper detonators are not uniform in length?  If you look up Krytron's you will learn how much current and voltage go to the slappers.   Look it up in the wiki.   For fun, calculate the velocity factor of a very sharp spike of current and voltage through a wire.