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Information on Teller–Ulam hydrogen bomb design

  1. May 4, 2012 #1
    Hi there,

    I have a question about the Teller–Ulam hydrogen bomb design. This will be a long post , but I hope someone can answer it for me.

    When the first bombs were created, uranium device was simple enough to to figure out. Two sub critical masses of u-235 joined at..... I think it was 3000 feet per second to create a critical mass. I think from what I read tungsten carbide was use as a neutron reflector to get the reaction going to achieve an explosion. Correct me if I am wrong.

    The second bomb they dropped was a plutonium bomb. This gets a little complicated. From what I have read / watched, the plutonium was in a hollow sphere, because p-239 will fizzle if brought to critical mass. They then took high explosives and compressed the the sphere of plutonium to critical mass. Not sure if a tamper was needed. (correct me if I am wrong but I think a tamper is a neutron reflector)

    Anyway the to designs worked, but along comes the hydrogen bomb. The way I think this works is as folllows: plutonium atom bomb goes off, which is very hot turning the polystyrene foam (basically styrofoam) into a plasma which in turn with the xrays given off sets the hydrogen fusion device to go off.

    So basically I am just wondering with the ICBM MIRVS, do they still use the implosion technique, or do they use a neutron generator to set off the plutonium device, and if so do they use a tamper.

    Thanks for taking a look at this. I am very tired and am going to go to bed now, but I hope someone can answer this. I cannot find any information in documentaries, or on google.

    Thank you.
  2. jcsd
  3. May 4, 2012 #2
    I would be surprised if the current ICBM designs weren't still classified...
  4. May 4, 2012 #3


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    Certain information about the W88 warhead was leaked to the press. http://en.wikipedia.org/wiki/W88 has a graphic that should answer at least some of the questions in the OP.
  5. May 14, 2012 #4
    Ahhhh so they still do use the explosives to start the fission reaction. Wonder how they fit that into a tiny MIRV.
  6. May 14, 2012 #5
    bare sphere (unreflected) Pu critical mass is just about 6" dia. The oblate design is a little tighter about the middle.
  7. May 15, 2012 #6


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