SINBAD ABSTRACT NEA-1553/57
TUD Spectra Measurements (FNG Bulk Shield)
1. Name of Experiment: ------------------ TUD Measurement of Neutron and Photon Spectra in an ITER Bulk Shield Mock-up (1996) 2. Purpose and Phenomena Tested: ---------------------------- Determination of neutron and photon spectra in a neutronic mock-up of the International Thermonuclear Experimental Reactor (ITER) shielding system irradiated with 14-MeV neutrons. 3. Description of Source and Experimental Configuration: ---------------------------------------------------- The 14-MeV d-T Frascati Neutron Generator (FNG, ) was the neutron source. The angular dependence of the source intensity is presented in Figure 1. The angular dependence of the source energy distribution is shown in Figure 2. The geometry of the mock-up is outlined in Figure 3. It consists of a combination of slabs made from the water equivalent material Perspex and the stainless steel SS316 (simulating shield-blanket and vacuum vessel) and has a front cross-section area of 100 cm x 100 cm. The total thickness of the assembly is 94.26 cm including a 1 cm thick Cu layer in front (simulating first wall). Behind this assembly a block of Cu and SS316 plates was arranged (simulating the coils for the toroidal magnetic field of the TOKAMAK; dimensions: depth 30 cm, area 47 cm x 47 cm). The rear part of the assembly was surrounded with a polythene shield covering also the last 30 cm of the Perspex/SS316 block in order to reduce room-return background. Neutron and photon spectra were determined in the mock-up on the central axis of the assembly at two positions: Position A: Measurement behind the 6 cm thick Perspex layer inside a SS316 slab, at a total penetration depth 41.5 cm from the front of the assembly (Cu 1 cm, SS316 26.08 cm, and Perspex 14.42 cm). Position B: Measurement in a SS316 layer at the total penetration depth 87.6 cm from the front of the assembly (Cu 1 cm, SS316 59.82 cm, and Perspex 26.78 cm). The detectors were placed on the axis of the d-beam of the neutron generator. 4. Measurement System: ------------------ A NE213 scintillator was employed for simultaneously measuring the neutron spectra for energies E>1 MeV and the photon spectra for energies E>0.2 MeV. For each registered event both the pulse-height and a pulse-shape parameter were recorded to distinguish between neutrons and photons. Pulse-height distributions from three different hydrogen-filled proportional detectors, one methane-filled proportional detector and a stilbene scintillator were used for determining the neutron flux spectra for energies ranging from 20 keV up to about 3.6 MeV, overlapping with the NE213 spectra [2-6]. Measurement uncertainties are provided with the tabulated spectra and are between 2 and 10 %. 5. Description of Results and Analysis: ----------------------------------- Neutron energy spectrum: The NE213 pulse-height spectra were unfolded by the DIFBAS code  with a response matrix developed at Physikalisch-Technische Bundesanstalt Braunschweig , to obtain spectral fluxes. The evaluation procedure of the proton recoil spectra from the proportional detectors and from the stilbene scintillator consisted in an iterative differentiation with inclusion of the following corrections: wall effect, non-linear light output function, anisotropy effect of stilbene, energy dependent sensitivity of the stilbene crystal and correction of neutron reactions on carbon resulting in alpha-particles. The results are shown in Figure 4. The neutron energy spectra represent a combination of the partial spectra obtained with the different detectors which were in each case corrected for material and size of the detector to a spherical detection volume of 2.0 cm radius filled with SS316. Photon energy spectrum: The pulse-height distribution from the NE213 detector for photons was unfolded with the DIFBAS code  with a response matrix calculated with the MCNP code. The results are shown in Figure 5. Also the photon energy spectra represent the spectral fluences in a SS316 sphere with radius of 2 cm and were normalized to one source neutron. Calculations: Examples of calculations carried out with the 3-D Monte Carlo code MCNP-4A  and the data libraries FENDL-1  and FENDL-2  are presented (Figure 6, Figure 7) . The geometry model for MCNP-4A including neutron source backing and the experimental environment (walls, floor, racks, ...) is given by the input file as well as a FORTRAN subroutine for MCNP source description. The input data for the 2D discrete ordinates transport calculation  are provided, including inputs for the codes TRANSX, GIP, GRTUNCL and DORT. 6. Special Features: ---------------- None 7. Author/Organizer: ---------------- Experiment and analysis: H. Freiesleben, D. Richter, K. Seidel, S. Unholzer Technische Universitaet Dresden Institut fuer Kern- und Teilchenphysik D-01062 Dresden Germany W. Hansen Technische Universitaet Dresden Institut fuer Energietechnik D-01062 Dresden Germany U. Fischer, Y. Wu Forschungszentrum Karlsruhe Institut fuer Kern- und Energietechnik P.O. Box 3640 D-76021 Karlsruhe Germany M. Angelone, P. Batistoni, M. Pillon ENEA Centro Ricerche Energie Frascati Settore Fusione - Divisione Neutronica Via E. Fermi 27 C.P. 65 I-00044 Frascati (Rome) Italy Compiler of data for Sinbad: K. Seidel Technische Universitaet Dresden Institut fuer Kern- und Teilchenphysik D-01062 Dresden Germany Reviewer of compiled data: I. Kodeli, A. Trkov Institute Jozef Stefan, Jamova 39, 1000 Ljubljana, Slovenia E-mail: firstname.lastname@example.org, email@example.com 8. Availability: ------------ Unrestricted 9. References: ----------  M. Martone, M. Angelone, M. Pillon, The 14 MeV Frascati Neutron Generator, Journal of Nuclear Materials 212-215 (1994) 1661-1664; M. Pillon, M. Angelone, A. V. Krasilnikov, 14 MeV Neutron Spectra Measurements with 4% Energy Resolution using Type IIa Diamond Detector, Nucl. Instr. Meth. in Phys. Res. B101 (1995) 473-485.  H. Freiesleben, W. Hansen, D. Richter, K. Seidel, S. Unholzer, P. Batistoni, M. Pillon, M. Angelone, Investigation of Neutron and Gamma-ray Spectra in a Blanket Mock-up of the International Thermonuclear Experimental Reactor (ITER), Proc. of the 9th Intern. Symp. on Reactor Dosimetry, Prague, Czech Republic, 2-6 September 1996, Editors: H. Ait Abderrahim, P. D'hondt and B. Osmera, World Scientific, Singapore, 1998, p. 391-396.  H. Freiesleben, W. Hansen, D. Richter, K. Seidel, S. Unholzer, U. Fischer, Y. Wu, M. Angelone, P. Batistoni, M. Pillon, Measurement and Analysis of Spectral Neutron and Photon Fluxes in an ITER Shield Mock-Up, Fusion Technology 1996, Proc. of the 19th. Symp. on Fusion Technology, Lisbon, Portugal, 16-20 September 1996, C. Varandas and F. Serra (editors), Elsevier Science B.V., Amsterdam, 1997, p. 1571-1574.  H. Freiesleben, W. Hansen, D. Richter, K. Seidel, S. Unholzer, U. Fischer, Y. Wu, M. Angelone, P. Batistoni, M. Pillon, Measurement of Neutron and Gamma Spectral Fluxes in the Shielding Assembly, Report TU Dresden, Institut fuer Kern- und Teilchenphysik, TUD-IKTP/96-04, November 1996.  H. Freiesleben, W. Hansen, D. Richter, K. Seidel, S. Unholzer, U. Fischer, Y. Wu, M. Angelone, P. Batistoni, M. Pillon, Neutron and Photon Flux Spectra in a Mock-up of the ITER Shielding System, Fusion Engineering and Design 42 (1998), Proc. of the Fourth Intern. Symp. on Fusion Nuclear Technology, Tokyo, April 6-11, 1997, M.A. Abdou (Ed.), Elsevier Science B.V., Part C, p. 247-253.  U. Fischer, H. Freiesleben, W. Hansen, D. Richter, K. Seidel, S. Unholzer, Y. Wu, Test of evaluated data from libraries for fusion applications in an ITER shield mock-up experiment, International Conference on Nuclear Data for Science and Technology, Trieste, May 19-24, 1997, Conference Proceedings Vol. 59, p. 1215-1217, G. Reffo, A. Ventura and C. Grandi (Eds.), SIF, Bologna, 1997.  M. Tichy, The DIFBAS Program - Description and User's Guide, Report PTB-7.2- 193-1, Braunschweig 1993.  S. Guldbakke, H. Klein, A. Meister, J. Pulpan, U. Scheler, M. Tichy, S. Unholzer, Response Matrices of NE213 Scintillation Detectors for Neutrons, Reactor Dosimetry ASTM STP 1228, Ed. H. Farrar et al., American Society for Testing Materials, Philadelphia, 1995, p. 310-322.  J. F. Briesmeister (Ed.), MCNP - A General Monte Carlo N-Particle Transport Code, Version 4A, Report, Los Alamos National Laboratory, LA-12625-M, November 1993.  S. Ganesan and P. K. McLaughlin, FENDL/E - evaluated nuclear data library of neutron interaction cross-sections and photon production cross-sections and photon-atom interaction cross-sections for fusion applications, version 1.0, Report IAEA-NDS-128, Vienna, May 1994.  M. Herman, A. B. Pashchenko, Extension and improvement of the FENDL library for fusion applications (FENDL-2), Report INDC(NDS)-373, IAEA Vienna, 1997.  U. Fischer, Y. Wu, W. Hansen, D. Richter, K. Seidel, S. Unholzer, Benchmark Analyses for the ITER Bulk Shield Experiment with EFF-3.0, -3.1 and FENDL-1, -2 Nuclear Cross-Section Data, IAEA FENDL-2 Consultants' Meeting, October 12-14, 1998, Vienna.  I. Kodeli, Report on 1999 Activity on ND-1.2.1 (extracts), EFF/DOC-698, EFF Meeting, Issy-les-Moulineaux NEA-DB (Nov. 1999)  P. Batistoni, M. Angelone, U. Fischer, H. Freiesleben, W. Hansen, M. Pillon, L. Petrizzi, D. Richter, K. Seidel, S. Unterholzer: Neutronics Experiment on a Mock-up of the ITER Shielding Blanket at the Frascati Neutron Generator, Fusion Engineering Design 47 (1999) 25-60 10. Data and Format: --------------- FILE NAME bytes Content ----------------- ------ ------- 1 tud-abs.htm 15.446 This information file 2 tud-exp.htm 66.231 Description of Experiment 3 MCNP4A.inp 59.091 3-D model for MCNP-4A calculations 4 source.for 45.178 FORTRAN subroutine for MCNP source description 5 TRANSX.inp 1.929 Input Data for TRANSX cross-section preparation 6 GIP.inp 2.510 Input Data for GIP cross-section mixing 7 GRTUNCL.inp 3.888 Input Data GRTUNCL first collision source code 8 DORT.inp 6.606 Input Data for DORT 9 TUD-fig1.gif 5.242 Fig. 1: Angular dependence of the source (preview) 10 TUD-fig2.gif 9.505 Fig. 2: Energy/angular dependence of the source (preview) 11 TUD-fig3.gif 12.709 Fig. 3: Geometry of the experimental mock-up (preview) 12 TUD-fig4.gif 9.259 Fig. 4: Neutron spectra at positions A and B (Experiment) (preview) 13 TUD-fig5.gif 8.872 Fig. 5: Gamma spectra at positions A and B (Experiment) (preview) 14 TUD-fig6.gif 13.752 Fig. 6: Neutron spectra at positions A and B (Calculation) (preview) 15 TUD-fig7.gif 12.692 Fig. 7: Gamma spectra at positions A and B (Calculation) (preview) 16 TUD-fig1.tif 18.978 Fig. 1: Angular dependence of the source (high quality) 17 TUD-fig2.tif 41.394 Fig. 2: Energy/angular dependence of the source (high quality) 18 TUD-fig3.tif 46.568 Fig. 3: Geometry of the experimental mock-up (high quality) 19 TUD-fig4.tif 33.966 Fig. 4: Neutron spectra at positions A and B (Experiment) (high quality) 20 TUD-fig5.tif 30.350 Fig. 5: Gamma spectra at positions A and B (Experiment) (high quality) 21 TUD-fig6.tif 1.412.874 Fig. 6: Neutron spectra at positions A and B (Calculation) (high quality) 22 TUD-fig7.tif 1.510.931 Fig. 7: Gamma spectra at positions A and B (Calculation) (high quality) File TUD-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). Tab. 1: Angular dependence of the source Tab. 2: Angular/energy dependence of the source energy distribution Tab. 3: Geometrical arrangement of the bulk shielding assembly Tab. 4: Chemical composition of stainless steel SS316 Tab. 5: Parameters of the neutron detectors Tab. 6: Neutron spectrum at position A (Experiment) Tab. 7: Neutron spectrum at Position B (Experiment) Tab. 8: Photon spectrum at Position A (Experiment) Tab. 9: Photon spectrum at Position B (Experiment) Tab.10: Neutron spectra at Position A (Calculation) Tab.11: Neutron spectra at Position B (Calculation) Tab.12: Photon spectra at Position A (Calculation) Tab.13: Photon spectra at Position B (Calculation) The figures describing the geometry of the experiment and the results are included in GIF and TIF formats.