SINBAD ABSTRACT NEA-1553/18
Osaka Nickel Sphere Benchmark Experiment (OKTAVIAN)
1. Name of Experiment: ------------------ Osaka Nickel Sphere Benchmark Experiment (OKTAVIAN) (1983) 2. Purpose and Phenomena Tested: ---------------------------- Neutron leakage spectra from a 32 cm diameter nickel sphere were measured between 30 keV and 15 MeV by the time-of-flight technique using a 14 MeV D-T neutron generator. 3. Description of the Source and Experimental Configuration: -------------------------------------------------------- A 300 keV Cockcroft-Walton type accelerator, OKTAVIAN of Osaka University was used to accelerate deuterons to a kinetic energy of 245 keV. The deuteron beam was led through a narrow tube to the centre of a nickel sphere where pulsed 14.1 MeV monochromatic neutrons were produced by the T(d,n)He-4 fusion reaction. The source strength is angle dependent (see Figures 3 and 4). The 32 cm diameter nickel sphere consisted of 99.63% Ni. 4. Measurement System and Uncertainties: ------------------------------------ The detectors used were: Detector Diameter Thickness Energy covered (cm) (cm) (MeV) --------------------------------------------------------------------- NE-213 scint. 12.7 5.08 0.03-15 NE-213 scint. 5.08 5.08 (14) neutron source monitor --------------------------------------------------------------------- Measurements of neutron spectra were carried out for high energy region (between 1 MeV and 15 MeV) and low energy region (30 keV to 15 MeV). Energy dependent statistical errors, large below about 0.04 MeV, elsewhere 1 - 10%. The uncertainty of the source spectrum in the 14 to 15 MeV energy range is about 8 %. 5. Description of Results and Analysis: ----------------------------------- Leakage current energy spectrum of neutrons was measured in "absolute values" by the time-of-flight technique between 30 keV and 15 MeV, about 9.5 m from the sphere centre. The detectors could view the entire surface of the sphere. Run-to-run neutron source monitoring was done using NE-213 detector which viewed directly the d-t source and was located at 482 cm from the target. The experimental configuration is suitable for one-dimensional modelling, although for more accurate results an explicit geometrical model including source anisotropy is recommended. Calculational models for the MCNP-4B code is provided. Comments: --------- Several inconsistencies were found in the originally proposed MCNP-3A input model, so this model was abandoned. Two input models for the MCNP-4B code are provided instead. The first is a simple spherical model with an isotropic source. In the second model the sphere geometry and the collimators are treated explicitly and the source anisotropy is taken into account. The neutron leakage spectrum calculated with the second model agrees very well with the measured one. The experiment seems to be of sufficient quality for nuclear data validation purposes. 6. Special Features: ---------------- None 7. Author/Organizer ---------------- Experiment and analysis: Akito Takahashi,J. Yamamoto, K. Sumita Faculty of Nuclear Engineering Department of Engineering Osaka University 2-1 Yamadaoka, Suita-shi Osaka-fu, 565 Japan TeleFax: +81-06-877-3264 E-Mail: a63010a@center.osaka-u.ac.jp (for Y.M) or d63182a@center.osaka-u.ac.jp (for A.T) T. Kasahara, H. Hashikura, M. Akiyama, Y. Oka, S. Kondo Nuclear Engineering Research Laboratory, Faculty of Engineering University of Tokyo Tokai-mura, Ibaraki 319-11, JAPAN Compiler of data for Sinbad: I. Kodeli OECD/NEA, 12 bd des Iles, 92130 Issy les Moulineaux, France E-mail: ivan.kodeli@ijs.si Reviewer of compiled data: A. Trkov Institute Jozef Stefan, Jamova 39, 1000 Ljubljana, Slovenia E-mail: andrej.trkov@ijs.si 8. Availability: ------------ Unrestricted 9. References: ---------- [1] K. Sumita, A. Takahashi, T. Kasahara, et al: "Measurements of Neutron Leakage Spectra from 16 cm Radius Nickel Sphere", OKTAVIAN Report A-84-04 (1984) [2] A. Takahashi, J. Yamamoto, H. Hashikura, et al: "Measurement and Analysis of Neutron Leakage Spectrum from Nickel Sphere for 14 MeV Neutron Source", OKTAVIAN Report C-85-07 (1985) [3] A. Takahashi, J. Yamamoto, H. Hashikura, et al: "Measurement and Analysis of Neutron Leakage Spectrum from Nickel Sphere for 14 MeV Neutron Source", Journal of Nuclear Science and Technology, Vol.23, No.6, 477-486 (1986) [4] A. Takahashi: "Integral Neutronics Experiments at OKTAVIAN", OKTAVIAN Report B-83-01 (1983) [5] A. Trkov: "Comments on the Oktavian Nickel Sphere Benchmark", Institute Jozef Stefan, Ljubljana, Slovenia, IJS-DP-8096, July 1999. [6] NEA Nuclear Science Committee: "International Handbook of Evaluated Criticality Safety Benchmark Experiments, Nuclear Energy Agency", Organisation for Economic Co-operation and Development, NEA/NSC/DOC(95)03. [7] Yo Makita and Akito Takahashi: "IAEA Benchmark Problem Based on the Time-of-Flight Experiment on Nickel Sphere at OKTAVIAN/Osaka University", IAEA, http://ripcnt01.iaea.or.at/nds/databases/fendl/FENDL.htm. 10. Data and Format: --------------- DETAILED FILE DESCRIPTIONS -------------------------- Filename Size[bytes] Content ---------------- ----------- ------------- 1 okni-abs.htm 10.317 This information file 2 okni-exp.htm 30.530 Description of Experiment 3 mcnp1d.inp 6.174 Input Data 1 for MCNP-4B Code (simple spherical model B) 4 mcnp3d.inp 18.159 Input Data 2 for MCNP-4B (detailed model, A in text) 5 Ni-Fig1.tif 67.321 Figure 1: Plan view of the OKTAVIAN facility (high quality) 6 Ni-Fig2.tif 37.660 Figure 2: View of the experimental arrangement (high quality) 7 Ni-Fig3.tif 36.441 Figure 3: Angular dependence of the neutron source energy (high quality) 8 Ni-Fig4.tif 39.377 Figure 4: Angular dependence of the neutron yield (high quality) 9 Ni-Fig5.tif 19.757 Figure 5: Leakage neutron spectrum (high quality) 10 Ni-Fig6.tif 26.134 Figure 6: Leakage neutron spectrum (high quality) 11 Ni-Fig7.tif 65.276 Figure 7: Source spectra comparison (high quality) 12 Ni-Fig8.tif 100.120 Figure 8: Calculated leakage spectrum dependence on the source spectrum (high quality) 13 Ni-Fig9.tif 104.428 Figure 9: Calculated leakage spectrum dependence on the geometrical model (high quality) 14 Ni-F10a.tif 98.600 Figure 10a: Calculated leakage spectrum dependence on the nuclear data (high energy range) (high quality) 15 Ni-F10b.tif 16.114 Figure 10b: Calculated leakage spectrum dependence on the nuclear data (low energy range) (high quality) 16 Ni-Fig1.gif 14.381 Figure 1: Plan view of the OKTAVIAN facility (preview) 17 Ni-Fig2.gif 7.514 Figure 2: View of the experimental arrangement (preview) 18 Ni-Fig3.gif 10.307 Figure 3: Angular dependence of the neutron source energy (preview) 19 Ni-Fig4.gif 6.019 Figure 4: Angular dependence of the neutron yield (preview) 20 Ni-Fig5.gif 7.414 Figure 5: Leakage neutron spectrum (preview) 21 Ni-Fig6.gif 12.038 Figure 6: Leakage neutron spectrum (preview) 22 Ni-Fig7.gif 8.384 Figure 7: Source spectra comparison (preview) 23 Ni-Fig8.gif 12.211 Figure 8: Calculated leakage spectrum dependence on the source spectrum (preview) 24 Ni-Fig9.gif 12.415 Figure 9: Calculated leakage spectrum dependence on the geometrical model (preview) 25 Ni-F10a.gif 11.312 Figure 10a: Calculated leakage spectrum dependence on the nuclear data (high energy range) (preview) 26 Ni-F10b.gif 10.899 Figure 10b: Calculated leakage spectrum dependence on the nuclear data (low energy range) (preview) 27 OKTNI_2.pdf 1.083.954 Reference 28 OKTNI_1.pdf 692.505 Reference File OKNI_EXP.HTM contains the following tables: A table with the source neutron spectrum, and 2 tables of measured neutron leakage spectra (high and low energy range). Figures are stored in TIFF format using LZW compression and GIF (preview) format.