U.S.: Test Points to N. Korea Nuke Blast

Breitbart.com ^ | 10/13/06 | ROBERT BURNS

[verum ago]

The U.S. government has determined that one scientific test, among many conducted since North Korea's announced nuclear test, was consistent with a nuclear explosion, a senior administration official said Friday night.

The official, who spoke on condition of anonymity, cautioned that the administration has not made a definitive conclusion about the nature of the explosion.

"The betting is that this was an attempt at a nuclear test that failed," the official said. "We don't think they were trying to fake a nuclear test, but it may have been a nuclear fizzle _ an effort that failed." The official spoke on condition of anonymity because of the sensitive nature of the information.

[DejaJude]

The official, who spoke on condition of anonymity

nothing to see here, move on.

[Marine_Uncle]

Something is not right. Either fission was reached or it was not. What does a fizzile mean?
If to adequate sub critical masses of plutonium or U235 where brought together in the proper fashion to create the chain reaction, one gets an explosion relative to the amount of fissionable mass present. If it did not go boom, then there would be no explosion.
If for some strange reason as a few have suggested, they attempted to use a large quantity of conventional explosives to some how ram the two sub critical masses together in the required time frame, then this is indicative they are truly still in the dark ages concerning how to manufacture a crude low yield atom bomb.
The info we are getting in dribbles from different sources simply do not add up to an affirmative that they indeed where testing a atomic device along traditional methods.
As far as some stating they may have been testing a "dirty bomb". Jibberish.
A dirty bomb (don't confuse it with various type of atomic and thermonuclear weapons the US and Russians experimented with years back), is where one simply uses conventional explosives to spread radioactive isotopes outward. Why would they be doing an underground test for such a thing. Underground explosions along that line would not give one much usefull data as how such a device would work above ground.

[GSlob]

" Either fission was reached or it was not. What does a fizzle mean?"
Well, imagine a critical mass. While it remains critical, it produces a large amount of energy, but not instantaneously but at some finite and very high rate of so and so many Joules per picosecond, [let us assume that this rate is constant in the first approximation]. If it remains critical for long enough [still pretty short time], then 84x10¹⁵J [the energy of 20kT TNT] are produced. But if the criticality lasted not the whole necessary period [say, 1 millisecond for the sake of discussion], but , say, only 3% of it [say, lousy design, container failed and the criticality lasted only 30 microsecond instead of the whole millisecond] then at our assumed rate of energy output the thing would fizzle at only 3% of the energy - 600 ton TNT equivalent.

[Enchante]

I'm no nuclear scientist but I do stay in a Holiday Inn Express now and then.... I believe that if the device is not designed and engineered to near-perfection then it's possible to have only a partial chain-reaction that does not consume nearly all of the available uranium or plutonium. The energy produced would be only a fraction (perhaps even a small percentage) of what was sought...... Thus there would be some fission products but not nearly the output that was expected or hoped for by the Lunatic Troll of Pyongyang.

Anyway, that's what my high school physics teacher might have said, though he would have expressed it much more scientifically.......

[Fitzcarraldo]

If they tested an enhanced neutron device (neutron bomb), the blast profile would be deceptively minimal.

Why tear up roads, bridges and buildings in Seoul when you can kill only people, the NKs are thinking IMO.

[Charles Martel]

"...If it remains critical for long enough [still pretty short time], then 84x1015J [the energy of 20kT TNT] are produced. But if the criticality lasted not the whole necessary period [say, 1 millisecond for the sake of discussion], but , say, only 3% of it [say, lousy design, container failed and the criticality lasted only 30 microsecond instead of the whole millisecond] then at our assumed rate of energy output the thing would fizzle at only 3% of the energy - 600 ton TNT equivalent."

All I can say is...

:-)

[blazematrix]

Something is not right. Either fission was reached or it was not. What does a fizzile mean?

Hum, neutron (flash) tube burn out? If they are playing with fissile plutonium right?

Neutron Tube; tritium gas field tube, once + and - volts applied, the tritium rushes to the titanium target to emit neutrons.

[GSlob]

"If they tested an enhanced neutron device (neutron bomb)"
Judging from their other military programs like rocketry, while their leader is a deranged baboon, his engineers are perfectly sane and proceed from the simpler to the more complex. Given that their stock of fissionables is small, they would be more likely to stick with something which is simpler but works [1945-era designs] than spend their precious plutonium in advanced experimentation.

[blazematrix]

They must be doing a neutron bomb. 6 to 8 aluminum (field with PU) tubes around a neutron tube from the old USSR. The neutron tube needs to be at least <12 years old even to produce enough neutrons to start the reaction.

Don't know so little information.
BM

[patriciaruth]

I heard that Japan has a pretty sensitive neutrino detector.

Wonder if that was the "test" that was positive.

[djf]

It's not really an either/or situation.

During the Manhattan project, there was a physicist there who would often demonstrate the whole process by pushing two sub-critical pieces of Uranium together.

As they got closer, they would heat up and the neutron flux would start to go through the roof.

At one point, they got too close. He dived on them to separate them, forunately in time enough to save the people watching. But he was killed from burns and radiation poisoning.

A standard reactor, if there is such a thing, has more than a critical amount of fissionable material. But the control rods which are inserted absorb neutrons and keep the reactor from going critical. An relatively unknown accident happened I think at a Navy station reactor where they figure the rod was pulled out too much. They went n after they got control and couldn't find the technician who was supposed to be on duty.

They eventually found him. He was pinned to the ceiling by a fuel rod that had been rocketed out of the reactor.

So unless the pieces are put together quickly, and with the right cross sections, etc. odds are that it will get really, really, really hot, produce a flood of neutrons and various atomic debris, and basically evaporate itself.

[IYAAYAS]

Joules per picosecond

So what you're saying is: The US is to megajoules per attosecond what NK is to millijoules per microsecond? cool

[Fitzcarraldo]

I think the North Koreans had lots of information going in to avoid pitfalls and problems. They would want to deploy small warheads that could be used in efficient ways.
Rocketry is a different type of science/art.

[GSlob]

Well, I was just trying to illustrate the concept of atomic explosion as developing and lasting in time [with a very crude approximation of the steady state energy output]. But the point was that the energy output, while high, is not infinite, and if the time during which it is being produced, is cut short for whatever reason, then so is the total device output, aka TNT equivalent.

[kublia khan]

"The betting is that this was an attempt at a nuclear test that failed,"
Where do you find a N Korean Nuclear scientist?
In Kim's stew pot, thats where.

[PghBaldy]

I have assumed it was a nuke. I also think our govt is not going on the record until they have absolute proof. However, there is plenty of evidence that Bush thinks it was. Same with other nations. (As an aside, this may be completely off-base, but there is a TV show called Jericho, which is about a small town (Jericho) dealing with the aftermath of several nukes destroying at least several US cities. 'I think it may help the Repubs next month.)

[IYAAYAS]

The North Koreans might have the ability to build a large, crude atom bomb. They will never be able to build one light enough to mount on a long range missile. A thermonuclear weapon is farther off than their future.

[GSlob]

I doubt it. If anything, they would have a lot of rocketry info too, and from the same sources - and have we seen any of that? How long did it take them to progress from the old Scud to their most recent fizzle? Decades.

[PghBaldy]

Still, it is very disturbing. Kim Jung Il is very odd and looks funny. He is easily mocked. His weapons though should not be. Who is to say that given to Iranians, they couldn't work out the kinks? I wish the media would talk more about NK's links to other rogue states. People need to know how serious this is - people besides news junkies here and elsewhere.