Analysis of neutron spectra and fluxes obtained with cold and thermal moderators at IBR-2 reactor: Experimental and computer-modeling studies

  • A. I. Kuklin
  • A. D. Rogov
  • Yu. E. Gorshkova
  • P. K. Utrobin
  • Yu. S. Kovalev
  • A. V. Rogachev
  • O. I. Ivankov
  • S. A. Kutuzov
  • D. V. Soloviov
  • V. I. Gordeliy
Methods of Physical Experiment

Abstract

The results of experimental and computer-modeling investigations of neutron spectra and fluxes obtained with cold and thermal moderators at the IBR-2 reactor (Joint Institute for Nuclear Research (JINR), Dubna) are presented. These studies are for the YuMO small-angle neutron scattering (SANS) spectrometer (IBR-2 beamline 4). The neutron spectra have been measured for two methane cold moderators for the standard configuration of the SANS instrument. The data from both moderators under different conditions of their operation are compared. The ratio of experimentally determined neutron fluxes of cold and thermal moderators is shown at different wavelengths. Monte Carlo simulations have been carried out to determine the spectra for cold-methane and thermal moderators. The results of calculations of the ratio of neutron fluxes of cold and thermal moderators at different wavelengths are demonstrated. In addition, the absorption of neutrons in the air gaps on the way from the moderator to the investigated sample is presented. SANS with the protein apoferritin was done with both cold methane and a thermal moderator and the data were compared. The prospects for the use of a cold moderator for a SANS spectrometer at IBR-2 are discussed. The advantages of using the YuMO spectrometer with a thermal moderator with respect to the tested cold moderator are shown.

Keywords

Neutron Flux Nucleus Letter Neutron Spectrum Gain Factor Cold Neutron 

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Copyright information

© Pleiades Publishing, Ltd. 2011

Authors and Affiliations

  • A. I. Kuklin
    • 1
    • 2
  • A. D. Rogov
    • 1
  • Yu. E. Gorshkova
    • 1
  • P. K. Utrobin
    • 2
  • Yu. S. Kovalev
    • 1
  • A. V. Rogachev
    • 1
    • 3
  • O. I. Ivankov
    • 1
    • 4
  • S. A. Kutuzov
    • 1
  • D. V. Soloviov
    • 1
    • 4
  • V. I. Gordeliy
    • 1
    • 2
    • 5
    • 6
  1. 1.Joint Institute for Nuclear Research DubnaDubnaRussia
  2. 2.Moscow Institute for Physics and TechnologyDolgoprudnyRussia
  3. 3.Skobeltsyn Institute of Nuclear PhysicsMoscow State UniversityMoscowRussia
  4. 4.Taras Shevchenko National University of KyivKyivUkraine
  5. 5.Institute of Structural BiologyGrenobleFrance
  6. 6.Institute of Structural BiologyJuelichGermany

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