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FNG/TUD SiC EXPERIMENT
1. Name of experiment:
-------------------
TUD measurement of neutron and photon flux spectra in a silicon carbide
assembly (2001).
2. Purpose and phenomena tested:
-----------------------------
Transport data benchmark by determination of spectral neutron flux and
spectral photon flux at four positions in a thick block of SiC irradiated
with 14 MeV neutrons.
3. Description of source and experimental configuration:
-----------------------------------------------------
The Frascati Neutron Generator [1] was used as 14 MeV D-T neutron
source. The angular dependence of the source intensity is presented in
Fig. 1. The angular dependence of the source energy distribution is
given in Fig. 2.
The geometry of the assembly is shown in Fig. 3. The angle between the
deuteron beam of the neutron generator and an axis crossing neutron
source and centre of the detector was 0 degrees. The dimensions of the
SiC block, composed of bricks, were 45.7 cm * 45.7 cm * 71.1 cm of length
(x-axis). The tritium target of the neutron source was located at
z = -5.3 cm. The SiC material was described in the calculations with a
density of 3.158 g/cm3 and an elemental composition of 68.9 wt-% of Si,
30.8 wt-% of C, 0.19 wt-% of B, 0.079 wt-% of Al, and 0.014 wt-% of Fe.
The information on the concentration and heterogeneity of Boron may not
be reliably. B-10 content strongly influences the thermal neutron flux
and consequently the (n,gamma) reactions (e.g. gamma peak at 0.48 MeV from
thermal neutron capture in B-10).
Neutron and photon flux spectra were measured on the central axis of
the assembly at four positions (P1,...,P4) at x = 12.70, 27.94, 43.18 and
58.42 cm.
4. Measurement system:
----------------------
Neutron and photon pulse-height spectra were measured simultaneously
using an NE 213 scintillation spectrometer. The dimensions of the
cylindrical active volume of the detector were 3.8 cm in both height
and diameter. Its material had a mass density of 0.874 g/cm3 and an
elemental composition of 54.8 at-% H and 45.2 at-% C.
The scintillator was coupled to a photomultiplier by means of a 50 cm
long light guide. When the detector was located at one of the
positions (P 1 in Fig. 3), the other ones were filled with pieces of SiC.
5. Description of results and analysis:
---------------------------------------
Data evaluation:
The DIFBAS code developed at PTB Braunschweig [2,3] was employed for
unfolding the measured pulse-height distributions in order to generate
the neutron and photon flux spectra. They were obtained as absolute
fluxes, as the response matrices have been determined on an absolute
scale by detailed simulations of experimental distributions from mono-
energetic neutron and photon sources with Monte Carlo codes.
Calculations:
A computational analysis was performed with the Monte Carlo code MCNP-
4C [4] using a full 3D model of the assembly, the neutron generator and
the experimental hall. Nuclear data were taken from the FENDL/MC-2.0
data library [5] except for Si-28, for which EFF-3.0 [6] data were used.
The spectra were calculated as average flux in the scintillator volume by
means of the track length estimator of MCNP.
Results are shown in Figs. 4, 5, 6, 7, 8, 9, 10 and 11. More details
are given in Ref. [7].
For the activation foil and TLD measurements on the same SiC block see
FNG Silicon Carbide Experiment.
6. Special features:
----------------
None
7. Authors/Organizer:
------------------
Experiment and analysis:
K. Seidel, H. Freiesleben, C. Negoita, S. Unholzer
Technische Universitaet Dresden
Institut fuer Kern- und Teilchenphysik
D-01062 Dresden
Germany
U. Fischer, Y. Chen, R. L. Perel
Forschungszentrum Karlsruhe
Institut fuer Reaktorsicherheit
D-76021 Karlsruhe
Germany
M. Angelone, P. Batistoni, M. Pillon
Associazione ENEA-EURATOM
Settore Fusione - Divisione Neutronica
Via E. Fermi 27
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
OECD/NEA, 12 bd des Iles, 92130 Issy les Moulineaux, France
8. Availability:
-------------
Unrestricted
9. References:
-----------
[1] M. Angelone, M. Pillon, P. Batistoni, M. Martini, M. Martone, V.
Rado, "Absolute experimental and numerical calibration of the 14
MeV neutron source at the Frascati Neutron Generator", Rev. Sci.
Instr. 67(1996)2189.
[2] M. Tichy, "The DIFBAS Program - Description and User's Guide",
Report PTB-7.2- 193-1, Braunschweig 1993.
[3] 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.
[4] J. F. Briesmeister (Ed.), "MCNP - A general Monte Carlo n-particle
transport code", version 4C, Report LA-13709, Los Alamos National
Laboratory, 2000.
[5] H. Wienke, M. Herman, "FENDL/MG-2.0 and FENDL/MC-2.0 - The
processed cross section libraries for neutron and photon transport
calculations", Report IAEA-NDS-128, Vienna, 1998.
[6] S. Tagesen, H. Vonach, "Evaluation of neutron cross sections for
fusion relevant materials", EFFDOC-785, NEA Data Bank, Nov. 2001.
[7] H. Freiesleben, C. Negoita, K. Seidel, S. Unholzer, Y. Chen, U.
Fischer, R. L. Perel, M. Angelone, P. Batistoni, M. Pillon,
"Measurement and analysis of neutron and gamma-ray flux spectra in
Tungsten", Report TUD-IKTP/02-02, Dresden, 2002, EFFDOC-822.
[8] U. Fischer, R. Perel and Y. Chen, Monte Carlo Transport, Sensitivity
and Uncertainty Analyses for the TUD Benchmark Experiment on SiC,
EFFDOC-815
[9] K. Seidel, M. Angelone, P. Batistoni, Y. Chen, U. Fischer, H.
Freiesleben, C. Negoita, R. L. Perel, M. Pillon, S. Unholzer,
Measurement and Analysis of Neutron and Gamma-Ray Flux Spectra in Sic
Fus. Eng. Design 69 (2003) 379.
[10] Y. Chen, U. Fischer, I. Kodeli, R. L. Perel, M. Angelone, P. Batistoni,
L. Petrizzi, K. Seidel, S. Unholzer, Sensitivity and uncertainty
analyses of 14 Mev neutron benchmark experiment on Silicon Carbide,
Fus. Eng. Design 69 (2003) 437-442.
10. Data and Format:
---------------
DETAILED FILE DESCRIPTIONS
--------------------------
No. File name Size (kB) Content
------------- --------- ---------
1 tudsic-a.htm 12,313 This abstract
2 tudsic-e.htm 41,669 Description of experiment
3 tudsic-c.htm 13,557 Description of transport calculations
4 mcnp.inp 20,360 3-D model for MCNP-4C code
5 source.for 39,959 FORTRAN subroutine for MCNP source description
6 fig1.jpg 27,072 Fig. 1: Angular dependence of the neutron source
7 fig1.ps 71,157 Fig. 1 (ps format)
8 fig2.jpg 50,616 Fig. 2: Neutron source energy/angular distribution
9 fig2.ps 850,273 Fig. 2 (ps format)
10 fig3.jpg 24,883 Fig. 3: Geometry of the assembly
11 fig3.ps 27,754 Fig. 3 (ps format)
12 fig4.jpg 33,108 Fig. 4: Neutron spectra at position P-1
13 fig4.ps 27,643 Fig. 4 (ps format)
14 fig5.jpg 32,832 Fig. 5: Neutron spectra at position P-2
15 fig5.ps 28,006 Fig. 5 (ps format)
16 fig6.jpg 32,204 Fig. 6: Neutron spectra at position P-3
17 fig6.ps 27,654 Fig. 6 (ps format)
18 fig7.jpg 33,119 Fig. 7: Neutron spectra at position P-4
19 fig7.ps 27,612 Fig. 7 (ps format)
20 fig8.jpg 33,662 Fig. 8: Gamma-ray spectra at position P-1
21 fig8.ps 26,254 Fig. 8 (ps format)
22 fig9.jpg 34,696 Fig. 9: Gamma-ray spectra at position P-2
23 fig9.ps 26,456 Fig. 9 (ps format)
24 fig10.jpg 32,920 Fig. 10: Gamma-ray spectra at position P-3
25 fig10.ps 26,351 Fig. 10 (ps format)
26 fig11.jpg 35,094 Fig. 11: Gamma-ray spectra at position P-4
27 fig11.ps 26,654 Fig. 11 (ps format)
28 eff-822.pdf 123,534 Reference [7] EFFDOC-822
29 eff-815.pdf 1,008,339 Reference [8] EFFDOC-815
30 soft22j39.pdf 71,152 Reference [9]
31 soft-22.pdf 236,191 Reference [10]
Files tudsic-e.htm and tudsic-c.htm contain the following tables:
Tab. 1: Angular dependence of the source
Tab. 2: Angular dependence of the source energy distribution
Tab. 3: Spectral neutron fluences for P1...P4, experiment
Tab. 4: Uncertainties of the measured neutron fluences
Tab. 5: Spectral photon fluences for P1...P4, experiment
Tab. 6: Uncertainties of the measured photon fluences
Tab. 7: Spectral neutron fluences for P1...P4, calculation
Tab. 8: Spectral photon fluences for P1...P4, calculation
The figures describing the geometry of the experiment and the
spectral fluences are included as PostScript and jpg files.
SINBAD Benchmark Generation Date: 4/2004
SINBAD Benchmark Last Update: 4/2004
