1 / 12

Some fission yields for 235U (n,f), 239Pu (n,f), 238U (n,f) reactions in ΣΣ neutron spectrum

Some fission yields for 235U (n,f), 239Pu (n,f), 238U (n,f) reactions in ΣΣ neutron spectrum. Dr. Cristina Garlea National Institute for R&D of Physics and Nuclear Engineering “Horia Hulubei”, Magurele, Romania Dr. Ion Garlea SENDRA – Nuclear Technology Ltd., Bucharest, Romania.

jihan
Download Presentation

Some fission yields for 235U (n,f), 239Pu (n,f), 238U (n,f) reactions in ΣΣ neutron spectrum

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Some fission yields for235U (n,f), 239Pu (n,f), 238U (n,f) reactions in ΣΣ neutron spectrum Dr. Cristina Garlea National Institute for R&D of Physics and Nuclear Engineering “Horia Hulubei”, Magurele, Romania Dr. Ion Garlea SENDRA – Nuclear Technology Ltd., Bucharest, Romania

  2. ΣΣ–ITN facility in thermal column of VVR-S Magurele reactor 1 - ΣΣ–ITN system; 2 - CB4 screen; 3 - Vertical plug; 4 - Horizontal plug; 5 - Cavity in graphite

  3. Details of ΣΣ–ITN system 1 - Uranium converter 2 - CB4 screen 3 - Channels for instrumentation

  4. ΣΣ–ITN system

  5. Maneuvering cell

  6. Comparison between neutron spectrum calculatedby ANISN code and that determined by SAND II Characteristics: - conversion factor: 0.731 - average energy of spectrum: 0.791 MeV - flux (2 MW) E ≥ 10 keV: 3.385 x 1013 n/m2s E > 1 MeV: 8.1 x 1012 n/m2s

  7. Comparison between measured and calculated ΣΣ spectrum Characterization in the intermediate energy range ± 15% E < 0.1 keV multiple foil methods ± 5% 0.1 keV ≤ E ≤ 2 MeV spectrometry and calculation ± 5% E > 2 MeV multiple foil methods

  8. Method • Neutron flux measuring in the place of detector exposure by absolutely calibrated fission chambers (FC – 235U) • Exposure of fissionable detectors- irradiation in the central position of ΣΣ-ITN system- fluence > 1014 n/cm2 (2 MW reactor power)- packaging in 0.5mm Al • Flux monitoring by two monitors fission chambers- in the second vertical channel- in graphite block • Fission yields measuring by high resolution  spectrometry- PTB 408 152Eu calibration point standard source- 5 cm source – crystal distance- SAMPO software package

  9. Characteristics of fissionable detectors Note: Mass of alloys are certified by Reactor Experiments USA with uncertainty of ± 1%.

  10. Results Fission yields in ΣΣ spectrum for 235U(n,f)

  11. Fission yields in ΣΣ spectrum for 239Pu(n,f) Fission yields in ΣΣ spectrum for 238U(n,f)

  12. Uncertainties • In neutron flux- fissionable deposit mass 1.6%- statistics 1.0%- monitoring 0.8% • In activation rate- fitting and background 0.62 – 4.7% subtraction- absolute efficiency 1.8 – 2% calibration of Ge(Li) crystal- statistics 1 – 3.8%

More Related