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 1. Name of Experiment:
    FNG Benchmark Experiment on Tungsten (2001)   

 2. Purpose and Phenomena Tested:
    The purpose is to validate the W cross sections in the European Fusion
    File (EFF), as tungsten is a candidate material for high flux component
    in the fusion reactor and its development is pursued in the European
    Fusion Technology Program. 
    The experiment [1, 2] was performed at the 14 MeV Frascati Neutron
    Generator (FNG). 

 3. Description of Source and Experimental Configuration:
    The 14-MeV d-T Frascati Neutron Generator (FNG, [3]) was the neutron
    source. The angular dependence of the source intensity is presented in
    Figure 1 and in Table 1. The angular dependence of the source energy 
    distribution is shown in Figure 2 and is given in Table 2.
    The geometry of the mock-up is outlined in Figure 4. 
    It consisted of a block of a tungsten alloy, DENSIMET, produced by PLANSEE,
    in pieces of various shapes, assembled to obtain a size of about 
    42-47 cm (L) x 46.85 cm (H) and 49 cm in thickness and located in front
    of the FNG target, 5.3 cm from the neutron source. Most of the material 
    (about 1.5 ton) is DENSIMET-176 type (92.3% W, 2.6% Fe, 4.2% Ni).
    A layer of DENSIMET-180 (about 0.25 ton, 7 cm height, composition 95.0% W,
    1.6% Fe, 3.4% Ni) was used in the central part of the block were the
    measurements are done (Figs. 4-8), and contains the lateral access
    channels (diameter 5.2 cm) for locating detectors of the various types
    (activation foils, TLD holders, active spectrometers).

 4. Measurement System:
    The following quantities are measured :

        a - Neutron reaction rates by activation foils
        b - Nuclear heating by thermo-luminescent detectors (TLD-300)

    Eight different reactions: 197Au(n,g), 55Mn(n,g), 115In(n,n), 58Ni(n,p),
    56Fe(n,p),  27Al(n,a), 58Ni(n,2n), 90Zr(n,2n) and 93Nb(n,2n) were used to
    derive the neutron flux, from low energy up to the fusion neutron peak.
    The reaction rates were measured in four experimental positions at different
    depths from the block surface, using the radiometric techniques based upon
    the use of absolutely calibrated HPGe detectors. During the activation foil
    measurements, the lateral access channels were completely closed by means of
    4 ad hoc cylinders made of DENSIMET  180, a thin slot was realised (4.4 mm)
    to locate activation foils in position, using a thin Al holder. The foils
    were irradiated in three irradiations: in the first one Zr, Al and Mn foils
    were irradiated, the foils arrangement is described in the MCNP input file
    ZrAlMn.mcp; in the second one Nb, Ni and Au foils were irradiated, the
    foils arrangement is described in NbNiAu.mcp; in the last irradiation
    Fe and In foils were irradiated, the foils arrangement is described in
    FeIn.mcp. The experimental results are given in Table 4. 

    Gamma heating was measured using TLD-300 dosimeters (CaF2:Tm). TLDs
    calibration was performed using Co-60 secondary standard, from 50 mGy up to
    4 Gy in air, converted into absorbed dose in TLD-300 using the photon energy
    attenuation coefficients from Hubble [4].
    Seven TLDs chips (3.2x3.2x0.9 mm3 each) were located in each experimental
    position, using the same experimental arrangement as for the activation foils,
    and enclosed in a perspex  holder 1 mm thick. The experimental arrangement is
    described in the MCNP input file mcnp_tld.inp.The measured dose in TLD-300 is
    given in Table 5. 

 5. Description of Results and Analysis:
    The experiment was analysed by using the Monte Carlo code MCNP-4C [2, 5] using
    for W, Fe and Ni the point-wise cross sections derived from EFF-2.4 and
    FENDL-2.0 [6]. In the case of EFF calculation, the Fe cross section were
    taken from EFF-3.0. The MCNP model of the experimental set-up was is given
    in ZrAlMn.mcp, NbNiAu.mcp and FeIn.mcp for the activation foils measurements, 
    and in mcnp_tld.inp for the TLD measurements. The track length estimator was
    used (tally 4 of MCNP) for fluxes and reaction rates calculation, while the
    gamma heating is calculated from the gamma energy deposition over the TLD
    cells (tally 6 of MCNP). All dosimetric reactions needed for the calculation
    of reaction rates were taken from IRDF-90.2 library [7]. The calculated
    reaction rates and gamma doses (C) are given in Tables 6 and 7 respectively,
    together with the MCNP statistical uncertainty.

    Deterministic transport and cross section sensitivity/uncertainty analyses
    using the DORT, TWODANT and SUSD3D codes are presented in [8], [9] and [10].
    The following input data used in these analyses are included here:
    - TRANSX (cross section preparation),
    - GRTUNCL and DORT (uncollided/first collision source and transport
    - TWODANT (neutron transport using first collision approach).
    The 2-dimensional cylindrical geometry model used in the DORT and TWODANT
    deterministic transport calculations is shown in Figure 10.

 6. Special Features:

 7. Author/Organizer:
    Experiment and analysis:

    P. Batistoni, M. Angelone, M. Pillon, L. Petrizzi 
    Centro Ricerche Energie Frascati
    UTS Fusione  
    Via E. Fermi 27
    C.P. 65
    I-00044 Frascati (Rome) 

    Compiler of data for Sinbad:
    P. Batistoni
    Centro Ricerche Energie Frascati
    UTS Fusione  
    Via E. Fermi 27
    C.P. 65
    I-00044 Frascati (Rome) 

    Reviewer of compiled data:
    I. Kodeli
    OECD/NEA, 12 bd des Iles, 92130 Issy les Moulineaux, France

    The experiment and the corresponding analysis was performed in the framework
    of the EFDA (European Fusion Development Agreement) Task (TTMN-002-2002).

 8. Availability:

 9. References:

    [1] P. Batistoni, M. Angelone, L. Petrizzi, M. Pillon, Measurements
        and Analysis of Neutron Reaction Rates and of Gamma Heating in
        Tungsten, MA-NE-R-003, ENEA, Dec. 2002
    [2] P.Batistoni, M. Angelone, L. Petrizzi and M.Pillon, Neutronics
        Benchmark Experiment on Tungsten, presented at ICFRM-11 (2003),
        to be published in Journal of Nuclear Materials
    [3] M. Martone, M. Angelone, M. Pillon, The 14 MeV Frascati Neutron 
        Generator, Journal of Nuclear Materials 212-215 (1994) 1661-1664;
    [4] J.H. Hubble, Photon mass attenuation and energy-absorption
        coefficients from 1 keV up to 20 MeV, Int. J. Appl. Rad. Isot.
        33 (1982) 1269
    [5] Briesmeister, J. F. (Ed.), MCNP - A general Monte Carlo
        n-particle transport code, version 4C, Report LA12625, Los
        Alamos, September 1999.
    [6] M. Herman, A. B. Pashchenko, Extension and improvement of the
        FENDL library for fusion applications (FENDL-2), Report
        INDC(NDS)-373, IAEA, Vienna, 1997.
    [7] N. P. Kocherov, P. K. McLaughlin, The International Reactor
        Dosimetry File (IRDF-90), Report IAEA-NDS-141, Rev. 2, Oct. 1993.
    [8] I. Kodeli, Analysis of Benchmark Experiment on Tungsten Using
        DORT, TWODANT and SUSD3D Deterministic Analysis Tools, 
        EFF Meeting, Issy-les-Moulinaux (Jan. 2003)
    [9] I. Kodeli, Analysis of FNG Benchmark Experiment on Tungsten Using DORT,
        TWODANT and SUSD3D Deterministic Codes, EFFDOC-867 (April 2003)
   [10] I. Kodeli, Tungsten Benchmark Experiments: Re-analysis Using JENDL-3.3,
        EFFDOC-885 (Nov. 2003)
   [11] I. Kodeli, Cross-Section Sensitivity Analysis of 14 MeV Neutron
        Benchmark Experiment on Tungsten, Journal of Nuclear Materials,
        Vol. 329-333, Part.1, P. 717-720 (2004)

10. Data and Format:

  FILE     NAME      bytes   Content
  ---- -----------   ------  -------
   1   fngw-a.htm    13,300  This information file 
   2   fngw-e.htm    26,634  Description of Experiment
   3   fngw-c.htm     6,233  Transport calculations - description & results
   4   source.for    45,178  FORTRAN subroutine for MCNP source description
   5   FeIn.mcp      89,670  3-D model for MCNP-4C calculation of
                             activation reaction rates (Fe and In foils)
   6   NbNiAu.mcp    91,581  3-D model for MCNP-4C calculation of
                             activation reaction rates (Nb, Ni and Au foils)
   7   ZrAlMn.mcp    91,649  3-D model for MCNP-4C calculation of
                             activation reaction rates (Z, Al and Mn foils)
   8   mcnp_tld.inp 132,050  3-D model for MCNP-4C calculation of gamma dose rates
   9   trx-w.inp      1,027  Input data for TRANSX cross-section preparation
  10   dort-w.inp     9,235  Input data for GRTUNCL first collision source and
                             DORT transport codes
  11   2dant-w.inp   12,663  Input data for TWODANT transport code
  12   fig1.gif       5,242  Fig. 1: Angular dependence of the source 
  13   fig2.gif       9.505  Fig. 2: Energy/angular dependence of the source
  14   fig3.gif       9,633  Fig. 3: Geometry of FNG target
  15   fig4.gif      10,267  Fig. 4: Y-Z view of FNG-W mock-up with detectors (X=0)
  16   fig5.gif      12,247  Fig. 5: Y-Z view of FNG-W (X=0) 
  17   fig6.gif       9,761  Fig. 6: X-Y view of FNG-W (-3.5 cm < Z < 3.5 cm)
  18   fig7.gif       7,133  Fig. 7: X-Y view of FNG-W (-15.5 cm < Z < -3.5 cm)
                             and (3.5 cm cm < Z < 15.5 cm)
  19   fig8.gif      11,982  Fig. 8: X-Z view of the mock-up (Y=0)
  20   fig9.gif       5,636  Fig. 9: Geometry of TLD detector
  21   fig10.jpg     88,233  Fig. 10: Geometry model used in codes DORT and TWODANT 
  22   enea-w.pdf   709,900  Reference 1
  23   kodeli-w.pdf 311,454  Reference 8
  24   eff-867.pdf  376,727  Reference 9
  25   eff-885.pdf  170,688  Reference 10
  26   kyoto03.pdf  201,723  Reference 11

    Files fngw-e.htm and fngw-c.htm contain the following tables:

    Tab. 1: Angular dependence of the source
    Tab. 2: Angular/energy dependence of the source energy distribution 
    Tab. 3: The chemical composition and the density of DENSIMET-176 and 
            of DENSIMET  180
    Tab. 4: Measured neutron reaction rates
    Tab. 5: Measured absorbed dose in TLD
    Tab. 6: MCNP calculated reaction rates - C/E ratios
    Tab. 7: MCNP calculated absorbed dose in TLD - C/E ratios

    The figures are given in gif format.

SINBAD Benchmark Generation Date: 1/2004
SINBAD Benchmark Last Update: 4/2006