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U233 immediate fission products ?

  1. Apr 27, 2012 #1
    Hi, what are the immediate fission products of U233 ? Is the first fission reaction of U233 same as U235 producing Ba and Kr but just different isotopes than U235 ? I would appreciate any help.

  2. jcsd
  3. Apr 27, 2012 #2


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    The fission product elements are much the same, however, one starts with 2 fewer neutrons.

    U-235 + n => U-236* => f.p. + 2 or 3 n

    U-233 + n => U-234* => f.p. + 2 or 3 n


    Last edited by a moderator: May 5, 2017
  4. Apr 27, 2012 #3
    Thank you ! But, then a small question, is U233 chain reaction self sustainable since it release fewer neutrons ?
  5. Apr 27, 2012 #4


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    One would be interested in

    η = reproduction factor = number of neutrons produced per neutron absorbed in fuel
    > 2 implies breeding is possible

    ν (nu) = number of neutrons produced per fission

    Code (Text):
    Isotope  Thermal η   Fast η
      U-235      2.07        2.30
      Pu-239     2.11        2.70
      U-233      2.30        2.45
    Ref: http://www.if.uidaho.edu/~gunner/ME443-543/LectureNotes/LMFBR.pdf

    http://energyfromthorium.com/2006/07/29/wash-1097-appendix-a-reactor-physics/ [Broken]
    It's probably better to obtain a copy of WASH-1097.

    One can also construct a tighter (hex or triangular) lattice similar to that of a VVER-1000. Or one could use a CANDU (deuterium moderated) system, or a graphite moderated system using SiC/C clad fuel. Flouride salt is another possibility.

    And one can minimize the parastic absorption of neutrons by exclusing Ni-based alloys from the reactor internals, to the extent possible.

    This might be of interest.
    Last edited by a moderator: May 5, 2017
  6. Apr 29, 2012 #5
    http://energyfromthorium.com/ has a java application which can let you compare the fission product spectrum from different nuclear fuels.
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