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Ispra Iron Benchmark Experiment (EURACOS)


 1. Name of Experiment:
    Ispra Iron Benchmark Experiment (EURACOS) (~1986)

 2. Purpose and Phenomena Tested:
    Study of the neutron deep penetration in homogeneous materials commonly 
    used in the construction of advanced reactors: Fe (and Na). Flux and 
    spectra were measured up to 130 cm in Fe.
    Experience gained from Aspis experiment was used to prepare this benchmark.

 3. Description of the Source and Experimental Configuration:
    The neutron source in a converter disc made of 6 trapezoidal U-Al alloy 
    plates forming an almost circular source with a diameter of 80 cm. The 
    space dependence of the source can be approximated by a cosinusoidal 
    radial profile. The spectrum is very similar to the U235 fission spectrum. 
    The EURACOS source strength (6.12E11 n/s) is about of the same order of
    magnitude as the one of Aspis.
    The converter is situated at the end of the thermal column of a TRIGA MARK II
    reactor (University of Pavia) in front of the irradiation chamber which is 
    surrounded by borated concrete walls of two different compositions.
    The first part extending from 35 cm to 162.4 cm from the converter 
    mid-plane (see Fig. 1) consists of ordinary concrete with a density of 
    2.3 g/cm3. The second part of the tunnel shield is made of heavy concrete 
    with a density of 3.6 g/cm3.
    The iron mock-up is a block of dimensions 145x145x130 cm3. A Boral plate 
    was placed between the source and the Fe block to reduce the low energy 
    flux originating in the thermal column.
    Use of large sulphur detectors, and low background measurements during a
    counting period of 5-6 half lives, made it possible to measure attenuation 
    up to 8 decades of fast neutrons.

 4. Measurement System and Uncertainties:
    The detectors used were:

    Detector                              Diameter Thickness    Error
                                            (cm)      (cm)       (%)
    S-32(n,p)P-32                             2     0.2 - 1   5.6 - 15.5
    In-115(n,n')In-115m                      (*)               10 - 15
    Rh-103(n,n')Rh-103m                      (*)                5 - 8
    Au-197(n,gamma)Au-198/under Cd (1mm)     1.0     0.01       5 - 8
    NE213 liquid scintillator spectrometer  volume = 3.35 cm3
    gas proportional counters                4.04 (spherical)
    (*) thin foils, can be neglected in the calculation.
    The gold foil consists of an Au/Al alloy with 0.1 wt% gold content. The 
    thickness of the Cd coating is 1 mm. 
    The energy resolution of the proton recoil spectrometers is between 5 and 15%.

 5. Description of Results and Analysis:

    Measurements with activation detectors were carried out approximately
    every 8 cm up to the depth of 60 cm with In(n,n'), 94 cm with S(n,p) and
    Rh(n,n'), and 133.5 cm with Au(n,gamma).
    The energy range between 14 keV and 10 MeV was covered with liquid scintillator
    spectrometer and gas proportional counters. 
    In the case of the scintillation counters the neutron spectra were furnished 
    by the NE213 code applying the differential method. For proportional gas 
    counters the spectra were unfolded by the SPEC4 code [9].
    The neutron spectra are given at 6 locations (22, 38, 54, 70, 86, 102 cm).
    As the authors are not completely confident that the unfolding was performed 
    according to state-of-the-art procedures, the original distributions of the 
    impulses measured by spectrometers and the detector geometry are included as 
    well for those who wish to carry out their own unfolding.

    MCNP-3 calculations performed using various flux estimators are described in [6].

    More recently this benchmark was studied by Dr Steven C. van der Marck, NRG,
    NL - 1755 ZG Petten (vandermarck@nrg-nl.com). He prepare a new input for
    MCNP-4c 'mcnp4-fe.inp' from the original MCNP-3 file (mcnp3-fe.inp). Few details 
    on the updates and results are given in eufe-cal.htm.

 6. Special Features:


 7. Author/Organizer
    Experiment and analysis:
    R. Nicks, G. Perlini, H. Rief
    Joint Research Centre, Ispra, 21020 Ispra (Varese), Italy
    Compiler of data for Sinbad:
    I. Kodeli
    OCDE/NEA, 12 bd des Iles, 92130 Issy les Moulineaux, France

    Reviewer of compiled data:
    H. Rief
    Joint Research Centre, Ispra, 21020 Ispra, Italy

 8. Availability:


 9. References:
   [1] Nicks R., Perlini G. and Rief H., Project and performances of the EURACOS II
       irradiation facility. Technical Note No., JRC Ispra. (1985)
   [2] Nicks R., Perlini G., Rief H., Fission neutron penetration in iron and 
       sodium-I. Activation measurements. Ann. Nucl. Energy 15, p.457 (1988)
   [3] Perlini G., Rief H., Fission neutron penetration in iron and sodium-II. 
       Neutron spectrometry. Ann. Nucl. Energy 16, p.189 (1988)
   [4] R. Nicks et al., "Iron and sodium benchmark experiments at EURACOS II-
       Part I: Activation measurements", NEACRP Specialists' Meeting on Shielding
       Benchmark, Paris, October 13-14, 1986.
   [5] G. Perlini, H. Rief, M.D. Carter, N.F. Murphy, The S32(n,p)P32 threshold
       detector and its application for fast neutron dosimetry (fast reactors and
       fusion reactors), Reactor Dosimetry, ECSC, ECC and EAEC, Brussels and
       Luxembourg, p.457 (1985)
   [6] H. Rief, Shamsi T. A., Aglietti-Zanon M. and Vittone E., EURACOS 10. 
       Team EN.102/017 (1987)
   [7] R. Garofoli, G. Gonano, G. Perlini, H. Rief, Fast neutron attenuation in
       large iron and sodium columns, 9th European Triga Conference, C.R.E.,
       Casaccia, Roma, (1986)
   [8] G. Perlini, M. Carter and S. Acerbis,  Neutron spectrometry in iron,
       Report EUR 11767 EN, Ispra. (1988)
   [9] P.W. Benjamin, The analysis of recoil proton spectra, AWRE 09/68, 
       Aldermaston, Berks (1968)

10. Data and Format:

        Filename     Size[bytes]   Content
    ---------------- ----------- -------------
  1 eufe-abs.htm      13.901  This information file 
  2 eufe-exp.htm      19.718  Description of experiment 
  3 EURFE.TB1         25.596  Tables of neutron spectra 
  4 EURFE.TB2        177.736  Tables of measured impulses 
  5 eufe-cal.htm       4.376  Description of transport calculations 
  6 mcnp3-fe.inp       6.722  Input Data for MCNP-3 Code 
  7 mcnp4-fe.inp      10.972  Input Data for MCNP-4c Code provided 
  8 Eurfe-1v.gif      10.969  Figure 1: Cross-section view of the EURACOS2 facility (preview) 
  9 Eurfe-2v.gif      23.274  Figure 2: Schematics of the experimental configuration (preview) 
 10 Eurfe-3v.gif      13.526  Figure 3: U-235 neutron converter (preview)                    
 11 Eurfe-4v.gif      10.556  Figure 4: Sulphur detector support device (preview) 
 12 Eurfe-5v.gif       7.976  Figure 5: MCNP geometry (preview) 
 13 Eurfe-6v.gif       9.149  Figure 6: SP2 proportional counter (preview) 
 14 eurfe-7.jpg      322.220  Figure 7: 3D view of the EURACOS2 iron experiment (preview) 
 15 EURFE-1V.TIF      26.832  Figure 1: Cross-section view of the EURACOS2 facility (high quality) 
 16 EURFE-2V.TIF      41.768  Figure 2: Schematics of the experimental configuration (high quality) 
 17 EURFE-3V.TIF      13.118  Figure 3: U-235 neutron converter (high quality)                    
 18 EURFE-4V.TIF      15.406  Figure 4: Sulphur detector support device (high quality) 
 19 EURFE-5V.TIF      11.520  Figure 5: MCNP geometry (high quality) 
 20 EURFE-6V.TIF      18.848  Figure 6: SP2 proportional counter (high quality) 
 21 eur_01.pdf     1.139.611  Ref.: R. Nicks et al., Project and Performances of the EURACOS II Irradiation Facility
 22 eur_02.pdf       537.382  Ref.: R. Nicks et al., Fission Neutron Penetration in Iron and 
                              Sodium-I. Activation Measurements.
 23 eur_03.pdf       503.082  Ref.: G. Perlini, H. Rief, Fission Neutron Penetration in Iron
                              and Sodium-II. Neutron spectrometry
 24 eur_04.pdf       655.408  Ref.: R. Nicks et al., Iron and Sodium Benchmark Experiments
                              at EURACOS II- Part I: Activation Measurements
 25 eur_05.pdf       185.260  Ref.: G. Perlini et al., The S32(n,p)P32 Threshold Detector
                              and its Application for Fast Neutron Dosimetry
 26 eur_06.pdf     3.944.371  Ref.: H. Rief et al., EURACOS 10. Team EN.102/017
 27 eur_07.pdf       384.022  Ref.: R. Garofoli et al., Fast Neutron Attenuation in Large
                              Iron and Sodium Columns
 28 eur_fe_8.pdf   2.721.200  Ref.: G. Perlini et al., Neutron Spectrometry in Iron
 29 eur_11.pdf       208.011  Ref.: H. Rief, Integral Shielding Benchmarks: Status of the EURACOS
                              Iron & Sodium Deep Penetration Experiments.
 30 eur_12.pdf       342.330  Ref.: G. Perlini, G. Gonano, The EURACOS Deep Penetration Iron Benchmark Experiment
 31 eur_13.pdf       404.659  Ref.: G. Perlini, H. Rief, The EURACOS Irradiation Facility 
 32 eur_15.pdf       397.685  Ref.: R.-D. Bachle et al., Consistency Check of Iron and Sodium
                              Cross-Sections with Integral Benchmark Experiments Using a Large Amount of Experimental Information
 33 eur_16.pdf       823.089  Ref.: Y. Yeivin, The EURACOS Activation Experiments: Preliminary Uncertainty Analysis, EUR 8011 EN
 34 eur_17.pdf       432.065  Ref.: G. Hehn et al., Adjustment of Neutron Multigroup Cross
                              Sections with Error Covariance Matrices to Deep Penetration Integral Experiments
 35 eur_18.pdf       638.823  Ref.: G. Pfister et al., Validation of Multigroup Cross-Sections of JEF-1 Data 
                              with Single Material Deep Penetration Benchmarks
 36 eur_19.pdf       440.870  Ref.: EURACOS Iron and Sodium Benchmark Analysis: A Comparison of JEFl and 
                              BMCCS1 Cross Sections in Deep Penetration Experiments
 37 eur_20.pdf       318.053  Ref.: G. Perlini et al., Interpretation of the EURACOS Iron and Sodium Benchmarks
 38 eur_21.pdf       200.479  Ref.: Yen-Wan H. Liu et al., Calculations of EURADOS Iron
                              Benchmark Experiment Using the Hybrid Method

    Files EUFE-EXP.HTM, EURFE.TB1, EURFE.TB2 contain the following tables:
     5 tables of chemical composition of materials present in the configuration
     8 tables of measured reaction rates
     6 tables of spectra derived from measurements using SPEC4 unfolding code
     6 tables of neutron spectra measurement and processing conditions
    41 tables of measured impulses used for unfolding an input example for SPEC 4

   Figures are included in GIF, JPG and TIF formats.

SINBAD Benchmark Generation Date: 07/1995
SINBAD Benchmark Last Update: 12/2003