Fast neutron induced fission neutron spectra below the incident energy

  • M. L. Woodring
  • J. E. Egan
  • G. H. R. Kegel
  • D. J. DeSimone


Fission neutron spectra from neutron induced fission in 235U and 239Pu for energies below that of the neutron inducing fission have been measured. The spectra were obtained for 1.5 MeV and 2.5 MeV incident neutrons. Previous accelerator-based fission neutron spectra measurements have been seriously complicated by time-correlated gamma-rays and scattered neutrons from the fission sample. Three barium fluoride detectors were placed near the sample undergoing induced fission and used to identify fission gamma rays. A coincidence of fission gamma-rays was used to gate a liquid scintillator neutron detector to distinguish fission events from other events. The fission neutron spectral shape and average energy measured in this experiment compare well to both previous measurements and prior theory and also suggest a dependence on incident neutron energy and mass of the fissioning nucleus. An overview of the experiment, a discussion of the results, and the importance of this work to homeland security are given.


Incident Neutron Fission Neutron Incident Neutron Energy Fission Neutron Spectrum Prompt Fission Neutron 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    P. Johannson, B. Holmqvist, Nucl. Sci. Eng., 62 (1977) 695.Google Scholar
  2. 2.
    H. Knitter, M. Copola, M. Islam, N. Ahmed, B. Jay, Proc. Conf. on Prompt Fission Neutron Spectra, IAEA Vienna, Aug. 25–27, 1971, p. 41.Google Scholar
  3. 3.
    A. Smith, P. Geunther, G. Winkler, R. McKnight, R. Nucl. Sci. Eng., 79 (1979) 357.Google Scholar
  4. 4.
    J. Frehaut, A. Bertin, R. Bois, Trans. Am. Nucl. Soc., 32 (1979) 732.Google Scholar
  5. 5.
    J. Boldeman, B. Clancy, D. Culley, Nucl. Sci. Eng., 55 (1979) 188.Google Scholar
  6. 6.
    P. Staples, J. Egan, G. Kegel, A. Mittler, M. Woodring, Nucl. Phys., A59 (1995) 41.Google Scholar
  7. 7.
    D. Madland, J. Nix, Nucl. Sci. Eng., 81 (1982) 213.Google Scholar
  8. 8.
    L. Beghian, G. Kegel, G. Couchell, J. Egan, P. Harrihar, T. Marcella, A. Mittler, D. Pullen, W. Schier, Nucl. Sci. Eng., 69 (1979) 191.Google Scholar
  9. 9.
    R. Vandenbosch, J. Huizenga, Nucl. Fission, (1973) 357.Google Scholar
  10. 10.
    P. Staples, J. Egan, G. Kegel, M. Woodring, D. DeSimone, P. Lisowski, 1994, Proc. Intern. Conf. of Nuclear Data for Science and Technology, Gatlinburg, Tennessee, ANS, Vol. 1, 1994, p. 151.Google Scholar

Copyright information

© Springer Science+Business Media, LLC. 2008

Authors and Affiliations

  • M. L. Woodring
    • 1
  • J. E. Egan
    • 2
  • G. H. R. Kegel
    • 2
  • D. J. DeSimone
    • 3
  1. 1.Pacific Northwest National LaboratoryRichlandUSA
  2. 2.University of Massachusetts LowellLowellUSA
  3. 3.Los Alamos National LaboratoryLos AlamosUSA

Personalised recommendations