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GT98
21st February 2003, 08:11
Over here:

http://www.newscientist.com/news/news.jsp?id=ns99993406

interesting

Jon P. Inghram
21st February 2003, 09:49
Forget about the UAV part... "quantum nucleonic reactor"?!? :eek:

High_Jumbllama
22nd February 2003, 07:34
Hmmm, what better way to get refined nuclear material to an enemy.

Dr Mordrid
22nd February 2003, 18:13
In extremely small quantities, and then they'd have trouble making sense out of how to use it;

It's called "IGE" for Induced Gamma Emission and has also been proposed as a pumping system for a gamma ray laser using various materials including Hafnium 178.

From Physical Review Letters, Jan. 1999;
X RAYS IN, GAMMA RAYS OUT

A laser is a machine for pumping energy (electrical, light, chemical, etc.) into a medium (liquid, gas, solid, etc.) whose atoms subsequently relax in a concerted way, producing coherent light. One of the obstacles to creating an x-ray or gamma laser is the inability to pack enough energy into the medium and have it sit there long enough until it can be extracted under the right circumstances.

One candidate medium for the job is isomeric hafnium. In nuclear physics isomers are nuclei that have the same number of neutrons and protons but differ in that for one nucleus one or more nucleons (protons or neutrons) are placed in an excited state.

Physicists .. . . begin with a sample (prepared at Los Alamos) of a metastable (31-year lifetime) isomer of Hf-178 with 4 participating nucleons, possessing a stored energy of 2.5 MeV. Then, like a transistor triggered by the merest of gate signals, the isomer material can, with the input of some x rays (amounting to only 1.6% of the output energy), produce induced gamma emission (IGE); thus x ray energy is stockpiled in the Hf and later extracted at higher gamma-ray energy.

The emitted rays are not coherent, however, so this is not yet an example of gamma lasing. (C.B. Collins et al. Univ. Texas at Dallas)

From another artice on the subject;
The energy storage capability for Hf-178 is reported variously as 1 billion joules per gram, 2.5 MeV per atom, and 0.05 exawatt per gram. What does that all mean in common terms? What is one billion joules? How much energy is in a gram of Hafnium at 2.5 MeV per atom? First, we go to a physics handbook and look up some conversion factors:

1 Joule = 1 watt-second
1Kilowatt-hour = 3.6 x 106 Joule
1MeV = 1.602x10-13 joule
1kt TNT = 4.184 x 1012 J = 2.61x1025 MeV
Avagadro's number 6.023 x 1023 atoms/mole

For the one billion joules we have:

(1x109J) (1KwH /3.6 x 106 J) = 277.8 kWh
or about 556 kitchen toasters running for 1 hour

To convert that to tons of TNT we use the following:

(1x 109 J) / (4.184 x 1012 J/kt)
= 0.239 x 10-3 kiloton
= 0.239 x ton
= 478 lbs. of TNTUniversity of Texas at Dallas links;

Essentials of Quantum Nucleonics (http://www.utdallas.edu/research/quantum/isomer/Tutorial.htm)

IGE for Gamma-ray Lasers (http://www.utdallas.edu/research/quantum/cqeseg3.htm)

It they get this to work efficiently......

Dr. Mordrid