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Author Topic: Do fission weapons need extra neutrons?  (Read 1027 times)

Offline taregg

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Do fission weapons need extra neutrons?
« on: 02/10/2013 15:22:42 »
 does fission weapons need extra neutrons in reaction..and fission power plant need less neutrons in raction...and why..
« Last Edit: 09/10/2013 09:28:14 by chris »


 

Offline syhprum

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Re: does fission weapons need extra neutrons...
« Reply #1 on: 02/10/2013 23:01:13 »
Fission weapons need a source of neutrons for rapid activation , early weapons used Polonium 210 (a great military secret) but modern weapons use an electronic vacuum tube device.
Back in the forties when diagrams of nuclear weapons were first published they were shown to use vacuum tube devices as the use of Polonium 210 was deemed to be top secret ! 
 

Offline CliffordK

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Re: does fission weapons need extra neutrons...
« Reply #2 on: 02/10/2013 23:07:43 »
Neutrons initiate the chain reaction fission events. 
A bomb needs the reaction event to progress very rapidly, and thus uses highly refined fissile materials.
A nuclear reactor needs sufficient speed in the reaction to generate a lot of heat without actually exploding.  So a nuclear rod may last over a year. 

I believe it is pretty simple in the nuclear reactor.  A single rod doesn't produce a high enough neutron density to initiate the fission cascade.  Bring several rods close to each other, and the reaction occurs.
 

Offline Pmb

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Re: does fission weapons need extra neutrons...
« Reply #3 on: 05/10/2013 04:24:20 »
does fission weapons need extra neutrons in reaction..and fission power plant need less neutrons in raction...and why..
I don't understand this question. What do you mean buy "extra neutrons"?

As explained above neutrons sources are used in weapons to make the reaction go super critical. Is that what you're asking about? As far as the energy released there is no need of any neutron at all in some fission reactions.

See http://home.comcast.net/~peter.m.brown/sr/nuclear_fission.htm
 

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Re: does fission weapons need extra neutrons...
« Reply #3 on: 05/10/2013 04:24:20 »

 

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