US military pioneers death ray bomb

Guardian ^ | 08/14/03 | David Adam and Suzanne Goldenberg

[fella]

Isn't that Elvira 'Mistress of the Night'?

[ffusco]

The problem with beta emitters is their decay energy is all over the place, so the sort of coherent stimulated emission phenomenon....


Duh!

[He Rides A White Horse]

Experts have warned that if the US scientists succeed in building a gamma ray bomb, it could force other countries to start nuclear programmes, or worse, encourage those who already possess nuclear weapons to use them.

'Experts'. More like a bunch of hand wringing communists lamenting United States superiority in virtually everything. Boo-hoo.

[He Rides A White Horse]

The bomb, which produces little fallout, blurs the distinction between conventional and nuclear weapons, and experts have already warned it could spark a new arms race.

Meanwhile our ChiCom friends are busy trying to create 'Rabbit Man'.........God knows what else they're working on.

These so-called 'experts' can stuff it. We must always strive to maintain military superiority in the world, especially in light of the barbarians populating most parts.

No need to let Johhny Commie and the rest of his friends catch up to us in anything. The United States is about the only hedge against these people.

[B-Chan]

Where do the neutrons come from in the fusion reaction? I thought that reaction consisted of two deuteriums (1 proton, 1 neutron apiece) fusing into one helium (2 protons, 2 neutrons). Where does the extra neutron come from?

The hydrogen fuel used in an H-bomb comes in the form of a solid substance called lithium-6 deuteride, or Li6D. (Li6D is a compound of lithium-6 and deuterium, a radioactive isotope of hydrogen.) When a neutron is absorbed by a molecule of Li6D, the molecule breaks up into a helium atom, an atom of H2 (deuterium) and one of H3 (tritium). The deuterium can then react with the tritium in fusion. This releases enormous amounts of energy, much greater than you would get in a fission reaction. The end products include a free neutron and a helium atom. Schematically:

Li6 + neutron => Helium-4 + Tritium + 4.7 MeV (energy)

then

Deuterium + Tritium => Helium-4 + neutron + 17.6 MeV (energy!)

The deuterium-tritium fusion portion of the two-step catalytic fusion process is where the shower of neutrons comes from.

[Formulae and description adapted from “Building the Bomb”]

[B-Chan]

Correction: the uranium shell used to construct the final fission stage in a fission-fusion-fission weapon is composed of naturally-occuring uranium, not highly enriched uranium. I apologize for the error.

[Safetgiver]

Umm, your'e probably right. Uhh, most assuredly so.

[inquest]

Thanks for the explanation. Now I'm left with one other question. You said that an H-bomb without the uranium tamper would just be a neutron bomb and not create a huge explosion. But if, as you say, the fusion reaction produces far more energy than a fission reaction, wouldn't the released energy heat up the surrounding air and cause a rapid expansion just like any other bomb? Is it because the energy from a fusion of nuclei wouldn't be released to the surrounding environment in the form of heat?

[RinaseaofDs]

Yeah it does!

I wonder what else you can do with gamma radiation. If you have a bunch of it to release anyway, what can you do with it? Can you heat water with it? If so, that's pretty good.

I honestly don't know, and I'm asking. I obviously know you can kill people with it.

[thegreatbeast]

With the Chinese for one. But that is not a bad thing in and of itself.

[B-Chan]

Thanks for the explanation. Now I'm left with one other question. You said that an H-bomb without the uranium tamper would just be a neutron bomb and not create a huge explosion.

Not exactly. What I said was that when an H-bomb with no tamper explodes, it shoots high-speed neutrons into everything around, killing most living things outright. However, it is still an H-bomb, and it still creates a powerful nuclear explosion when it goes off.

The only difference between a regular nuclear weapon and an enhanced radiation weapon (“neutron bomb”) is that the neutron bomb is customized so as to release a greater proportion of its explosive energy in the form of penetrating particle radiation (prompt neutrons) rather than as electromagnetic radiation (gamma and X-rays) as does a standard nuclear weapon. In both types, however, an explosion occurs.

The neutron bomb was invented as a weapon of last resort. During the Cold War, the Warsaw Pact and Soviet forces in Europe had huge tank armies, vastly larger than NATO's tank forces, and large mechanized infantry formations which dwarfed our own. Our plan was to use our technological advantages (cruise missiles, helicopters, A-10s, the M1 Abrams, etc.) to offset our disadvantage in numbers; however, it was by no means certain that even our most advanced weapons could keep the USSR from overrunning Europe with wave after wave of tanks and armored personnel carriers. If that had happened, our only alternative would have been to use nuclear weapons, which would have most likely led to the destruction of the countries we were fighting for, not to mention a global nuclear war. Even so, tactical nuclear weapons are not all that effective in mechanized combat; properly-prepared Soviet forces, protected by their heavy, armored vehicles, could have survived even nearby nuclear explosions.

The neutron warhead was designed to kill Soviet soldiers inside their tanks and mechanized infantry vehicles while causing as little damage to the surrounding area as possible. Exploded over a Soviet mechanized formation, the neutron bomb would have roasted the enemy soldiers in their vehicles, like tins of sardines under a blowtorch; the amount of neutrons released by the explosion would have caused the flesh to literally disintegrate on their bones. In addition, neutron radiation has the property of turning whatever it hits radioactve as well; any Soviet forces that survived the initial radiation blast would have been killed not long after by the secondary radiation from their own now-radioactive tank armor and other equipment.

The idea was that our forces could "cook" entire Soviet divisions with just a few bombs, stopping any advance and giving our forces the time they neded to regroup and counterattack. Thank God we never had to use the neutron bomb.

[NukeMan]

According to the article it only applies to nuclides in the metastable state; most fission products are not metastable - even gamma emitters.

[NukeMan]

A large multistage H-bomb gets half its total energy release from fusion, and the other half from natural Uranium tamper fissioning.

There are other sources of neutrons besides the ones B-Chan has listed: sometimes a plutonium-239 cylinder is put in the middle of the lithium deuteride cylinder and it fissions while being imploded (thus producing neutrons and power); tritium can be chemically imploded (really!!) to cause a fusion reaction and that also helps with the 'starter bomb' to boost yield.

[inquest]

tritium can be chemically imploded (really!!) to cause a fusion reaction and that also helps with the 'starter bomb' to boost yield.

That's fascinating. You'd think that we'd be able to use that ability for controlled fusion.

[B-Chan]

There are other sources of neutrons besides the ones B-Chan has listed: sometimes a plutonium-239 cylinder is put in the middle of the lithium deuteride cylinder and it fissions while being imploded (thus producing neutrons and power)

Correct. I left out a description of the Pu cylinder (“spark plug”) for the sake of simplicity, but thanks for filling in that info.

tritium can be chemically imploded (really!!) to cause a fusion reaction and that also helps with the 'starter bomb' to boost yield.

If I understand you correctly, you're referring to “boosted” fission weapons. In a standard fission bomb, the hollow center of the core contains a plutonium “pit” used as a source of prompt neutrons; this allows weapons designers to achieve supercitical mass (= boom) using smaller cores. In boosted designs, the core is left hollow, then filled with a deuterium-tritium gas. At the time of implosion, this gas is compressed by the core elements, flashes to plasma, and fuses, releasing energy and a flurry of neutrons that kick-starts the fission process, producing more boom per unit mass of uranium than the standard design.

[SAMWolf]

Watch out granny, they're gonna getcha!

[SAMWolf]

Been there in the 60's, It's stolen Martian technology

[GunnyHartman]

[B-Chan]

Google for “intertial confinement fusion” for info.

[Robert A Cook PE]

Hmmmmn.

Sounds phoney (a distraction answer only, incorrect and misleading maybe, not informative....?)

See, while each gamma ray is very energetic (as a photon of of a single high-energy wave) it by itself caries very, very little "energy" - Getting struck by tens of trillions of gamma rays a second doesn't even "heat up" your hand if you grab a chunk of highly radioactive material in your palm: the damage is celluar by individual rays striking individual atoms in the cells and breaking them up. This desctruction of the cell chemistry is what causes the radiation sickness/death.

So how could they "focus" the rays (emitted omni-directionally from random decay) so that the rays all go one direction and can be aimed? How do you "turn off" the device so it can be stored and transported?

(Realistically, a weapon might have to wait for ten-twenty years to be used only once, and even then, the "on" period could be only a matter of seconds, compared to weeks (or months) of waiting AFTER it is carried overseas and deployed!

If they don't collate" the beam, but only "aim" the shield so the rays only escape one direction - then they have wasted 99.9% of the total energy...which also doesn't make sense.