The research that could, perhaps, lead to nuclear isomer bombs one day remains contentious in America; the weight of the physics establishment says the science is unproven, even unlikely. But what is the rest of the world doing? In particular, what about the Russians, who carried out some of the earliest work in this area?And what about the Chinese?
Shortly after first writing about the potential for an isomer bomb, I came across an article in the Russian paper Nezavisimaya Gazeta. This was on 12th August 2003; for the 50th anniversary of the first Soviet hydrogen bomb, they interviewed Viktor Mikhailov, scientific director of the Federal Nuclear Center. (The original is in Russian, translation thanks to Babelfish.)
Q: But what still are the possibilities in principle of using the nuclear effects?
A: We have the also very large field of work with the nuclear energy. Besides the isotopes of fissionable elements there are the so-called isomers. Isotopes differ from each other only in terms of number of neutrons in the nucleus. But isomers have the same number of electrons, and protons, and neutrons. The entire difference is in the fact that the isomer is in an excited state, but can convert to stable state. And this also releases nuclear energy. Any transition from one state to another occurs with the release of energy. The fission energy of nuclei exceeds chemical energy 10 million times. But who says that a weapon this powerful is necessary these days? But the transition of isomers gives off thousands of times more energy than chemical reactions.
Q: This is way to the creation of a new generation of nuclear weapons?
A: It is difficult to say, developments are still under way today. I simply want to emphasize that nuclear energy is not only fission energy or fusion, but can be, for example, the transition energy of separate nucleons.
So the Russians also have a theoretical interest, at least, in isomer weapons.
In America, the most controversial research has involved trying to "trigger" -- get energy out of -- a Hafnium isomer. In Russia, there has been plenty of controversy over Hafnium, as well. A 2005 paper on induced decay of the nuclear isomer 178m2Hf and the 'isomeric bomb' written by E. V. Tkalya, is deeply skeptical of the physics involved.
However, I came across a more recent scientific paper, which puts a different light on hafnium triggering. The work was carried out by a team of Russian and Chinese physicists in the area of "resonance conversion" as an efficient triggering technique and was published in the journal Chinese Physics Letters.
Much of the argument about triggering energy release from Hafnium is about the size of the target. Imagine the Hafnium atom is a bomb, which you are trying to detonate by firing bullets at it. One school of thought says the critical area you need to hit is tiny; controversial, Darpa-funded researcher Carl Collins and his colleagues say that (according to his disputed results) it’s a billion times bigger.
The Russian and Chinese paper attempts to bridge the gap between these two, explaining how a resonance effect might make the target area tens of thousands of times larger than you would otherwise expect. It doesn’t fully account for the difference, and it relies on some assumptions which have yet to be proven.
It would be potentially alarming if the Russians and Chinese cracked the secret of isomer triggering and plunged while the scientific community dismissed it as physically impossible. But the paper on resonance conversion had a surprising footnote:
Supported by the DTRA [the US Defense Threat Reduction Agency] under contract No DTRA 01-02-M-0534
DTRA is one of the U.S. military agencies pursuing isomer research. In these international times, it is not so easy telling who is on which side.
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