Creating more efficient nuclear weapons?

[cosmicalstorm]

I was doing my daily Singularitard newsrun and came across this blurb which initially didn't so weird. But the I came across the bolded part. I know far too little physics to be sure if that claim is valid. By valid, I mean in the sense that it will have near term application ( and not the old <new exciting discovery that will possible lead to something awesome 50 years form now).

Dr. Bae gave an oral presentation and a poster presentation with Los Alamos National Lab on "Creating Nanostars with Buckyballs (C60)" at APS-SCCM Conference on July 8th and 9th.

Nanostars have been created and studied at Y. K. Bae Corp. by impacting buckyballs (C60) at hypervelocities (velocity over 100 km/s) in an innovative tabletop apparatus under the auspice of DTRA. The Nanostars are estimated to have ~10 TPa (100 million atmosphere pressure) transient pressures and convert ~35 % of impact kinetic energy into soft-x-ray energy. The ultrahigh-efficiency conversion is proposed to result from Dicke Superradiance of Metastable Innershell Molecular State (MIMS), originally discovered by Dr. Bae and his colleagues in 1994 at Brookhaven National Lab with the use of a large particle accelerator. The innovative usage of buckyballs and successful orders-of-magnitude scaling down of the apparatus size and complexity establish an innovative tabletop method of generating and studying matters in planetary or stellar interiors and open doors to numerous unprecedented applications.

This work could lead to vastly more efficient generation of x-rays at higher intensities.

It could also lead to far more powerful explosives and the replacement of the fission trigger in nuclear fusion bombs. Fusion bombs without fission triggers would have almost zero nuclear fallout.

Covalent bonds have 2-9 electron volts
Hydrogen bond have 0.04 to 0.13 eV
kinetic energy of neutrons produced by D-T fusion, used to trigger fission is 14.1
Average total energy released in the nuclear fission of one uranium-235 atom is 215 MeV

The MIMS material produces keV x-rays. A few hundred times more than regular covalent bond energy. Thousands of times less than nuclear fusion and fission energy levels.


http://nextbigfuture.com/2013/08/nanost ... meter.html

[Borgholio]

A pure fusion bomb would be a mixed blessing. With current nukes, it's not just the sheer damage output that prevents them from being used frequently, it's the radiation too. The explosion is actually less scary to most people than getting irradiated later on.

If you had a pure, clean fusion bomb, then yeah there'd be no fallout or lingering radiation...but that would also encourage people to use nukes more often since there wouldn't be any long-term consequences. A nuke would then become just a very large conventional explosive. So with no radiation to worry about, armies would begin using nukes for all sorts of things.

[Starglider]

If you had a pure, clean fusion bomb then yeah there'd be no fallout or lingering radiation...

All existing thermonuclear secondaries use deuterium-tritium fusion, which does not have direct radioactive byproducts but does spray fast neutrons everywhere, generating an instantaneous radiation dose and fallout via neutron activation.
Much less fallout than a fission bomb (assuming they can eliminate the fissile 'sparkplug' as well as the primary), but still a significant amount. For a genuinely clean bomb you'd need to use aneutronic fusion, which effectively impossible to weaponise (reaction cross section far too low) for any currently conceivable containment.

So with no radiation to worry about, armies would begin using nukes for all sorts of things.

I would expect the radiation to be low enough that it isn't likely to cause operational issues for militaries, but it would still be a major postwar environmental problem.

[Borgholio]

I was always under the impression that the neutrons emitted by fusion had to be sustained over a period of time to cause any kind of lingering radiation.

[Imperial Overlord]

I was always under the impression that the neutrons emitted by fusion had to be sustained over a period of time to cause any kind of lingering radiation.

The damage isn't from the neutrons hanging around and fucking with people. A fusion reaction kicks out a lot of fast neutrons. They, in turn, smash into other atoms and knock things loose. What's left of the atomic nucleus after the collision is often a radioactive isotope. They start kicking out alpha, beta, and gamma rays on their way down to becoming stable isotopes. Those are the radiation sources that get you.

[Borgholio]

The damage isn't from the neutrons hanging around and fucking with people. A fusion reaction kicks out a lot of fast neutrons. They, in turn, smash into other atoms and knock things loose. What's left of the atomic nucleus after the collision is often a radioactive isotope. They start kicking out alpha, beta, and gamma rays on their way down to becoming stable isotopes. Those are the radiation sources that get you.

Right, that's what I'm saying. How does the danger of the radioactive elements created by the neutron surge compare to the elements left behind after a plutonium fission reaction?

[Terralthra]

For the same size explosion, a fission radioactive fallout plume would probably be worse than a thermonuclear one. The trick is that they aren't the same size explosion; thermonuclear weapons are orders of magnitude bigger.

[TimothyC]

For the same size explosion, a fission radioactive fallout plume would probably be worse than a thermonuclear one. The trick is that they aren't the same size explosion; thermonuclear weapons are orders of magnitude bigger.

I don't know of any systemic research into fallout plume sizes, but IVY KING was a full test of a 500kt fission device - the current devices the US deploys mostly top out at about the same level. Something to keep in mind is that nuclear weapons designers want to wring every last erg out of the fissile material - that stuff is expensive, and the more energy you extract the cleaner the devices gets (you'll get less fallout if more of the fissile material is consumed).

Another factor that should be considered is the altitude of initiation - if you initiate low enough that you get a ground burst (where the fireball touches the ground), you get a lot more fallout than you do with an airburst.

[Terralthra]

Ivy Mike was a 2-stage fission-initiated thermonuclear fusion device, and had a yield of 10-12 Mt. Are you thinking of Ivy King?