[back to index] [experiment]
1. Name of Experiment:
------------------
KANT Spherical Shell Transmission Experiment on Beryllium
('KANT' stands for 'Karlsruhe Neutron Transmission Experiment')
2. Purpose and Phenomena Tested:
----------------------------
The purpose at the time of the experiment was mainly to clarify the
discrepancies found by other researchers in the effective neutron
multiplication of bulk beryllium assemblies with central 14 MeV neutron
sources. We recorded neutron leakage spectra from 5, 10 and 17 cm thick
spherical beryllium shells from the source energy down to less than 10 eV.
The experiment was performed at the Institut fuer Neutronenphysik und
Reaktortechnik of Forschungszentrum Karlsruhe from 1990 to 1994.
3. Description of Source and Experimental Configuration:
----------------------------------------------------
The neutron source was the T(d,n)He-4 reaction. A titanium-tritium target on
a copper backing was bombarded by a 150 keV deuteron beam. The source
strength was monitored by recording associated alpha particles using a
silicon surface barrier detector.
The spherical beryllium metal shells were placed in a concentric way around
the source. The inner shell diameter was 10 cm and the outer up to 44 cm. All
neutron leakage spectra were recorded at 60 degree emission angle with
respect to the deuteron beam.
4. Measurement System and Uncertainties:
-------------------------------------
Various detectors were employed to cover, in separate runs, the wide energy
range: an NE-213 liquid scintillator detector for energies above 3 MeV,
several different proton recoil proportional counter tubes for the range from
6 MeV down to about 50 keV, and the time-of-flight (TOF) technique for
energies below 100 keV. The background of wall scattered etc. neutrons was
always measured separately using a shadow cone.
The 1-standard-deviation uncertainty of every value in the spectra, including
all systematic and statistical sources of uncertainties, is estimated at 8%.
In addition to the above spectrum measurements, the spectra were also
recorded using the carefully calibrated Bonner sphere spectrometer of
Physikalisch-Technische Bundesanstalt, Braunschweig (PTB). This technique
offers only a modest energy resolution, but is sure to observe any neutrons
between the source energy and thermal energy. It was employed here mainly to
obtain an independent result on the total neutron multiplication. The results
obtained in this way were presented in Ref.[M95]. They agreed satisfactorily
with those of the more detailed spectral measurements.
5. Description of Results and Analysis:
-----------------------------------
The results, in the form of tabulated 178-group spectra, are found in files
fzkbe.tb1, fzkbe.tb2 and fzkbe.tb3). Some more details of the experiment are
found in file fzk-be_e.htm. For analyses, an MCNP model of the experiment with
17 cm shell thickness is given in file kantmcnp.i. It can easily be modified
for the 5 or 10 cm shell by changing the outer shell diameter accordingly.
Our own analysis [M95] revealed that the effective neutron multiplication
generally agreed well with 3-dimensional calculations using recent (at the
time) evaluated nuclear data. The relatively old Young and Stewart beryllium
evaluation[Y79], used in the EFF-1 library, appeared to underestimate the
emission of neutrons with less than about 100 keV from beryllium-neutron
collisions. On the other hand, the Be-9(n,2n) cross section of that
evaluation was found to be more correct than the newer one found in ENDF/B-VI.
Further benchmark calculations using this experiment have been reported by
Hayashi et al.[H94] and Tayama et al.[T01]. Perel et al.[F00] have made
Monte Carlo based cross section sensitivity studies using this experimental
configuration.
6. Special Features:
----------------
Other than in most experiments on fusion neutron transport, the leakage
neutron spectra were measured through the full energy range from the 14 MeV
peak down to thermal energy.
7. Author/Organizer:
----------------
Experiment and analysis:
U. von Moellendorff, H. Giese, F. Kappler, W. Eyrich, H. Fries,
Forschungszentrum Karlsruhe, Karlsruhe, Germany;
K. Hayashi, T. Tsukiyama, H. Ebi, R. Tayama,
Hitachi Engrg. Co., Hitachi-shi, Japan
Compiler of data for Sinbad:
U. Fischer
Forschungszentrum Karlsruhe, Institut fuer Reaktorsicherheit,
Postfach 3640, D-76021 Karlsruhe, Germany;
Reviewer of compiled data:
E. Sartori, I. Kodeli
OECD/NEA, 12 bd des Iles, 92130 Issy les Moulineaux, France
8. Availability:
------------
Unrestricted
9. References (quoted in this abstract or in the experiment description, file
fzk-be_e.htm):
----------
[B82] G. Bulski et al., Int. Conf. Nuclear Data for Science and Technology,
Antwerp, Sept. 1982
[D82] G. Dietze and H. Klein, Report PTB-ND-22 (1982) and unpublished upgrades
[E91] H. Ebi, W. Eyrich, H. Fries et al., Fus. Eng. Des. 18 (1991) 317-322
[F00] U. Fischer, R. L. Perel and H. Tsige-Tamirat, Fus. Eng. Des. 51-52
(2000) 761-768
[H94] K. Hayashi, U.v.Moellendorff, T. Tsukiyama et al., 'Fusion Technology
1994' (Eds. K. Herschbach et al.), Elsevier (1995), Vol. 2, 1349-1352
[Ka73] F. Kappler, D. Rusch and E. Wattecamps, Nucl. Instr. Meth. 111 (1973)
83-92
[Ke73] C.D. Kemshall, Report AWRE 031 (1973)
[M95] U. von Moellendorff, A.V. Alevra, H. Giese et al., Fus. Eng. Des. 28
(1995) 737-744
[T01] R. Tayama, T. Tsukiyama, K. Hayashi et al., Fus. Eng. Des. 55 (2001)
365-372
[Y79] P. G. Young and L. Stewart, Report LA-7932-MS, 1979
10. Data and Format:
---------------
DETAILED FILE DESCRIPTIONS
--------------------------
No. File name Size (kB) Content
------------- --------- ---------------
1 fzk-be_a.htm 7.76 This abstract
2 fzk-be_e.htm 7.65 Description of experiment
3 kantmcnp.i 10.4 MCNP input for 17 cm thick shell
4 fzkbe.tb1 3.61 Tabulated spectrum of 5 cm shell
5 fzkbe.tb2 4.15 Tabulated spectrum of 10 cm shell
6 fzkbe.tb3 4.15 Tabulated spectrum of 17 cm shell
7 kant.xls 90.0 Measured spectra from Be shells
8 fzk-be.pdf 630. Reference [M95]
SINBAD Benchmark Generation Date: 1/2004
SINBAD Benchmark Last Update: 3/2006
