Tuesday, September 5, 2017

Did North Korea Really Conduct An H-Bomb Test? Doubtful!

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Designs of primitive H-bombs (ca. 1952-55) from U.S. (top) and Soviet Union.

 As the U.S. press approaches panic over North Korea's most recent nuclear test, wiser and more sober heads have questioned whether it even makes the cut of a hydrogen bomb at all. Best estimates from the U.S Geological Survey, analysts at Rand Corporation and the Bulletin of the Atomic Scientists - based on a 6..3 Richter scale quake in the vicinity - are that the yield was 100 kilotons.  This is nowhere near the expected yield (500 kt - 1 megaton) of a minimal hydrogen fusion bomb.

According to Paul Richards, a researcher at Columbia University's Lamont-Doherty Earth Observatory, who studies the seismic signals of nuclear weapons test explosions:

"It does not seem large enough to be the mark of a true hydrogen bomb detonation."


"The limited number of (hydrogen bomb tests) that have been done underground in the few megaton range have magnitudes on in the high six or seven range. That would be a hundred times larger than this."

This is reinforced by Won-Young Kim, also a research scientist at Columbia University's Lamont-Doherty Earth Observatory who collaborates with Richards.   He observes that for a test of a supposedly more powerful device, the seismic signal bears a similarity to those of previous nuclear tests involving smaller devices.

Kim added in a CNBC interview:

 "The consensus is that a hydrogen bomb or thermonuclear device would be huge — the yield would be much bigger than that of a small nuclear bomb."

How is this? Let's go back to yield and mass delivery specs for earlier H-bombs, for which I show two designs above.   The U.S. original H-bomb (Teller-Ulam ) design shown in the top graphic, consists of a fission bomb - massive in itself  -  at one end of a heavy radiation case. At the other end is the thermonuclear charge, basically a cylinder with a neutron shield at one end (liquid deuterium inside it) and a thin 'spark plug' of plutonium mixed with tritium. At detonation, the radiation from the fission bomb reflects off the radiation casing and compresses the thermonuclear charge to many times its original density.

The compression then sparks a fission reaction in the mixed Pu- 3 H spark plug that compresses the fusion fuel simultaneously from the other side. The fusion material is now primed for fusion reactions which yield megaton scale release.

Given a similar design for the N. Korean weapon, the best explanation of what transpired is that the full implosion of  the thermonuclear charge failed to occur.  This means the high density needed for actual nuclear fusion - needed to overcome Coulomb repulsion, i.e. between like charged protons- did not occur. The result of 100 kt was merely an advanced atomic explosion, or "boosted" detonation,  but not a hydrogen fusion detonation.

By comparison, the U.S.  early 50s' 'Mike' design, once refined, came in at 1,360 kg  for total mass and the yield to mass ratio translating into just over a 1 megaton explosion (1.08 Mt).  This conforms to what Bruce Bennett, a senior analyst for Rand Corporation, a non-partisan think tank - said: "That type of explosion doesn't cause kilotons [of explosive yield], it causes megatons."

The message then, despite all the hype and the usual huff and puff from Trump, is not to panic. In the end most rational observers - like Adm. James Whitfield (Ret.) this morning, advise it's time to take a deep breath. According to Adm. Whitfield, Kim Jong Un is simply buying insurance against a U.S. invasion or attack such as we beheld with the regime change in Iraq in 2003.  Whitfield in a CBS interview this morning, emphasized that  Kim would never attack the U.S. first because he'd know it would mean his own annihilation and that of his country. That's the last thing he wants. He wants to stay in power.

Alarming at another level is the South Korean Defense Minister's request for a review of tactical nuclear weapons for his country.  Any such transfer would pose enormous risks, not only to the South Koreans, but increasing the chances of an accidental nuclear war that could see Russia and China enter as well. According to nuclear non-proliferation expert Catherine Dill, such a move would radically "increase the chance of miscalculation or unintended escalation.". It is simply not on.:

As the WSJ's Gerald Seib (p. A4, today) put it: "most experts simply don't believe a preemptive strike on North Korea is feasible because it would trigger a conflict that could leave millions of South Koreans dead."   Thereby rendering even more reprehensible Trump's tweet about South Korea's President Moon "appeasing" the North.   Delivered like a true coward who himself has zero 'skin in the game except for his big mouth.

This is why, as former CIA Acting Director Mike Morrell put it, all parties - certainly here in the U.S. - including the bombastic "fire and fury" Trump and Nikki Haley ("Kim is begging for a war"), need to tone down the rhetoric.  It is such misguided brinksmanship that often sets off wars such as World War I.   Sadly, we have a nincompoop who tweets like a five -year old in charge and not the mature person we really need, say a JFK- who got us through the Cuban Missile Crisis.

Intelligent citizens also ought to ignore the trade threats of Trump, the man-baby,  who responded to the latest North Korean missile test by warning about halting trade with China ("any country doing business with North Korea").  As analysts noted, in today's WSJ (p. A6, 'Trump's Threats Put China Trade At Risk') such a precipitous move "would be nearly impossible to implement without wreaking havoc on the U.S. economy".

How much havoc? Enough to also "hurt American factories and workers" - the ones Trump promised to help out with jobs, and most of whom likely voted for the imp.

This is because after Mexico and Canada, China is the U.S. 3rd largest trade partner at $479 b in goods and services, according to Capital Economics analyst Andrew Kenningham.. Cutting that out in response to China not dealing with the North the way Trump wants, would be the mark of a moron. But then, look who we have leading the country.

A veritable toad who doesn't know any better than to issue tweets concerning a potential nuclear conflict - for which cooler heads and serious negotiations are in order. Not deranged outbursts from a narcissist authoritarian's Id.

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