Open AccessNeutron dosimetry of the HFIR hydraulic facility
Author(s) -
Sheikh T. Mahmood,
Saed Mirzadeh,
K. Farrell,
J.V. Pace,
B.M. Oliver
Publication year - 1995
Language(s) - English
Resource type - Reports
DOI - 10.2172/34421
Subject(s) - neutron flux , physics , nuclear physics , neutron temperature , center (category theory) , fission , flux (metallurgy) , neutron , isotope , isotopes of helium , dosimetry , radiation flux , atomic physics , radiation , materials science , chemistry , nuclear medicine , metallurgy , crystallography , medicine
The total, fast, and thermal neutron fluxes at five axial positions in the High Flux Isotope Reactor (HFIR) hydraulic tube have been measured using bare and/or cadmium-covered activation, fission, and helium accumulation flux monitors. The spectrum-averaged, one-group cross sections over selected energy ranges for the reactions used in the measurements were obtained using cross sections from the ENDF/B-V file, and the target region volume-integrated spectrum was calculated with DORT, a two-dimensional discrete ordinates radiation transport code. The fluxes obtained from various monitors are in good agreement. The total and fast (>l MeV) neutron fluxes vary from 1.6 {times} 10{sup 19} n/m{sup 2} {center_dot} s and 1.6 {times} 10{sup 18} n/m{sup 2} {center_dot} s, respectively at the ends (HT-1 and -9) of the facility to 4.0 {times} 10{sup 19} n/m{sup 2} {center_dot} s and 4.6 {times} 10{sup 18} n/m{sup 2} {center_dot} s, respectively, at the center (HT-5) of the facility. The thermal-to-fast (>1 MeV) flux ratio varies from about 5.4 at the center to about 6.7 at the ends of the facility. The ratio of fast flux greater than 0.1 MeV to that greater than 1 MeV is 2.0 and stays almost constant along the length of the tube