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26-Fe- 56 NRG EVAL-FEB04 EUROPEAN JOINT COLLABORATION
DIST-JAN09 20090105
----JEFF-311 MATERIAL 2631
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
*************************** JEFF-3.1.1 *************************
** **
** Original data taken from: JEFF-3.1 Updated **
** Modification: Correction: inel thresh. MF12 **
******************************************************************
***************************** JEFF-3.1 *************************
** **
** Original data taken from: New evaluation **
** **
******************************************************************
********************** 20 - 200 MeV extension ********************
NRG-2004: n + Fe-56
Author: A.J. Koning and M.C. Duijvestijn, NRG Petten
************** G E N E R A L I N F O R M A T I O N *************
For energies below 20 MeV, information is given further down this
description. Since the 0 - 20 MeV part has already been subject
to an extensive evaluation procedure we have left it untouched.
For energies above 20 MeV, this evaluated data file is based on a
theoretical analysis with the nuclear model code TALYS [kon04],
version 0.56. The nuclear model parameters of TALYS have been
adjusted to reproduce the existing experimental data both below
and above 20 MeV to guarantee a smooth transition from the low to
the high energy part.
The resulting data file provides a complete representation of
nuclear data needed for transport, damage, heating,
radioactivity, and shielding applications over the incident
neutron energy range from 1.0E-11 to 200 MeV.
The high-energy part of this file is part of a larger collection
of isotopic evaluations over the whole energy range,
all created by running TALYS with input parameters that do not or
slightly deviate from the default values. The mutual quality of
these isotopic evaluations is thus relatively consistent.
The same set of nuclear models is used and, equally important,
the same ENDF-6 formatting procedures for each isotope. We have
intended to make this evaluation complete in its description of
reaction channels, and use a compact method to store the data.
All transport data above 20 MeV for particles, photons and
residual nuclides are filed using a combination of MF3,4 and
MF6. This includes cross sections, angular distributions, double-
differential spectra, photon production cross sections, and
residual production (activation) cross sections.
This evaluation can thus be used as both transport and
activation library. The high-energy part of this data file
has been created automatically using the ENDF-6 format generator
TEFAL.
##### ORIGIN
Data < 20 MeV : JEFF-3.0
Data 20-200 MeV: HINDAS collaboration
All data : Produced with TALYS code
*************************** T H E O R Y **************************
TALYS is a computer code system for the prediction and analysis
of nuclear reactions. TALYS simulates reactions that involve
neutrons, gamma-rays, protons, deuterons, tritons, helions and
alpha-particles, in the 1 keV - 200 MeV energy range and for
target nuclides of mass 12 and heavier. This is achieved by
implementing a suite of nuclear reaction models into a single
code system. It enables to evaluate nuclear reactions from
the unresolved resonance region up to intermediate energies. This
evaluation is based on a theoretical analysis that utilizes the
optical model, compound nucleus statistical theory, direct
reactions and pre-equilibrium processes, in combination with
databases and models for nuclear structure. For Fe-56, the
following output of TALYS above 20 MeV is stored in this data
file:
- Total, elastic and non-elastic cross sections
- Elastic scattering angular distributions
- Residual production cross sections
- Total particle cross sections, e.g. (n,xn), (n,xp),..
- Total particle energy spectra
- Total particle double-differential spectra
Here follows a short description of the used nuclear models:
##### OPTICAL MODEL
All optical model calculations are performed by ECIS-97 [ray94],
in TALYS used as a subroutine. The default optical model
potentials (OMP) used are the local and global parameterizations
of Koning and Delaroche [kon03]. These are phenomenological OMPs
for neutrons and protons which in principle are valid over the
1 keV - 200 MeV energy range, though the low energy boundary of
validity may differ from nucleus to nucleus (e.g. for the total
cross sections, experimental data are included directly in the
file for energies below that boundary). Solving the Schroedinger
equation with this OMP yields the total cross section, the
shape-elastic cross section, the shape-elastic angular
distribution, the wave functions for the direct reaction cross
sections (see below), the transmission coefficients for the
compound nucleus model (see below) and the reaction cross
sections for the pre-equilibrium model (see below).
For neutrons and protons, the used parameterization is given in
Eq. (7) of [kon03].
To calculate the transmission coefficients and reaction cross
sections for deuterons, tritons, helions and alpha particles, we
use OMPs that are directly derived from our nucleon potentials
using Watanabe's folding approach [mad88].
##### DIRECT REACTIONS
The built-in ECIS-97 is used for coupled-channels or DWBA
calculations for rotational or vibrational (or a combination of
these) nuclides. For Fe-56, DWBA was used to compute the direct
cross sections to several low-lying discrete levels:
Level Energy Spin/Parity Deformation parameter beta_L
1 0.846776 2.0+ 0.23900
2 2.085080 4.0+ 0.02200
3 2.657560 2.0+ 0.04500
5 2.959920 2.0+ 0.01500
8 3.122930 4.0+ 0.06500
9 3.369740 2.0+ 0.04500
10 3.388490 6.0+ 0.02800
14 3.602000 2.0+ 0.03800
17 3.755620 6.0+ 0.03000
19 3.832000 2.0+ 0.02300
In addition, a macroscopic, phenomenological model to describe
giant resonances in the inelastic channel is used. For each
multipolarity an energy weighted sum rule applies and a DWBA
calculation with ECIS-97 is performed for each giant resonance
state. The cross section is then spread over the continuum with a
Gaussian distribution.
##### COMPOUND NUCLEUS
For binary compound nucleus reactions we use the Hauser-Feshbach
model [hau52]. The transmission coefficients have been generated
with the aforementioned OMPs and the full j,l-dependence of the
transmission coefficients in the Hauser-Feshbach model is used.
For each nucleus that can be reached through a binary reaction,
several discrete levels and a continuum described by level
densities are included simultaneously as competing channels.
Multiple compound emission is continued until all reaction
channels are closed and the population distribution of all
residual nuclides is depleted, through gamma decay, until they
end up in the ground state or in an isomer.
For the level density, we take the composite formula proposed by
Gilbert and Cameron [gil65], consisting of a constant temperature
law at low energies and a Fermi gas expression at high energies.
For the level density parameter a we use the energy dependent
expression proposed by Ignatyuk [ign75] to take into account the
damping of shell effects at high excitation energy. We have
obtained the parameters for the Ignatyuk formula from a
simultaneous fit to all experimental D_0 values as present in the
RIPL library. If necessary, we adjust individual parameters to
obtain a better fit to experiment.
Gamma-ray transmission coefficients are generated with the
Kopecky-Uhl generalized Lorentzian for strength
functions [kop90], with giant dipole resonance parameters taken
from the RIPL library [rip98], and normalized with experimental
radiative widths [gar84].
##### PRE-EQUILIBRIUM REACTIONS
For pre-equilibrium reactions, which become important for
incident energies above about 10 MeV, we use the two-component
exciton model [kon04b], in which the neutron or proton types of
particles and holes are followed throughout the reaction. For
energies above 20 MeV, multiple pre-equilibrium emission up to
any order of particle emission was included in the calculations.
A parameterization for the squared matrix element is used that is
valid for the whole energy range of this evaluation.
For deuterons, tritons, helions and alpha-particles, an extra
contribution was added from the pick/up and knock-out reaction
model by Kalbach [kal01].
For photons, the model of Akkermans and Gruppelaar [akk85] was
applied, to simulate the direct and semi-direct capture
processes.
The angular distribution systematics by Kalbach [kal88] were used
to describe the angular distributions for all continuum
particles. An isotopic distribution for photons was adopted.
****** C O M P A R I S O N W I T H E X P E R I M E N T *****
This evaluation was performed simultaneously with other adjacent
isotopes, both for incident neutrons and protons. This enables,
when compared with a single-isotope effort, to put stronger
constraints on the produced calculated data, i.e. a globally
good comparison between TALYS and experimental data is requested
for all isotopes at the same time, while nucleus-specific input
(default or adjusted) parameters are consistently used for all
isotopes. Also, experimental data that is not available for the
isotope under study may be present, and tested, for adjacent
nuclides or for other projectiles. If these can be successfully
described by the models, a similar performance can be expected
for the present data file. Examples are the (n,xp)....(n,xa)
spectra for Fe-nat up to 96 MeV obtained within the HINDAS
project [sly03,lec03],as well as (n,xn) and (n,xp) data on Fe-nat
below 20 MeV [mat92,koz78,vil93,sod95,ban96].
##### TOTAL AND REACTION CROSS SECTIONS AND ELASTIC SCATTERING
We have used a dispersive local OMP for Fe-56. The parameters
do not deviate considerably from the parameters for the
conventional OMP described in [kon03].
Consult [kon03] for the complete experimental database of elastic
scattering angular distributions as well as total cross sections
and for a comparison of calculations and measurements over the
whole energy range.
##### OTHER PARTIAL CROSS SECTIONS
- (n,2n):
After tuning some level density paramaters the calculation agrees
well with the (n,2n) measurement by [cor78] at 20 MeV. Excitation
functions for discrete gamma-ray production associated with the
(n,2n)-process up to 40 MeV can be found in [dic90]. The gamma
line corresponding to the transition between level 1 and the
ground-state (L01->L00) are described within 25%. The same is
true for the transitions L02->L00 and L03->L00.
The gamma-rays belonging to L04->L02 and L04->L00 are largely
overpredicted by a factor of 2.
- (n,3n):
Calculations are compared to excitation functions for discrete
gamma-ray production associated with the (n,3n)-process up to
40 MeV [dic90]. The yield of the L07->L02 transition is described
perfectly and the L02->L01 and L01->L00 are overpredicted by
almost a factor of 2. Default level density parameters were used.
- (n,p):
Calculations are compared to excitation functions for discrete
gamma-ray production associated with the (n,p)-process up to
40 MeV [dic90]. The calculation overestimates the L03->L00
transition by 70%, the L09->L00 and L05->L00 yields are
underestimated by 30% and the L06->L00,L07->L00 and L08->L04
gamma-rays are nicely reproduced. Based on (,n,p)-data below
20 MeV, the temperature of the daughter nucleus was lowered
somewhat [chi89]
- (n,a):
The L03->L00 and L02->L00 gamma-rays from the (n,a) reaction are
well described by the calculation [dic90], without any fitting.
- (n,na):
The L04->L01 and L06->L02 gamma-rays from the (n,na) reaction are
well described by the calculation. The L01->L00 and L02->L01
transitions are overpredicted by 80% [dic90]. No fitting was
carried out.
##### PARTICLE SPECTRA
For Fe-56 two parameters in the default matrix element
parameterization of [kon04b] for pre-equilibrium reactions had to
be adjusted. The asymptotical value for matrix element at high
energies is multiplied by a factor of 0.3 and the constant for
the energy shift is multiplied by 0.48, to describe the
aforementioned cross sections and emission spectra
[mat92,koz78,vil93,sod95,ban96,mar83]. Furthermore, several state
density parameters have been altered by maximally 15% from the
default Z/15 (N/15).
For high-energy neutron and charged particle spectra, the average
quality is also determined by the pre-equilibrium model and its
global parameterization. Two experiments from the HINDAS project,
for neutron induced reaction spectra at 63 MeV [sly03] and 96 MeV
[lec03], have enabled us to better constrain the results, through
the aforementioned matrix element, for particle yields and
double-differential spectra for all ejectiles up to alpha
particles.
***************** F I L E I N F O R M A T I O N ****************
Only the data for E > 20 MeV are described here.
##### MF3: REACTION CROSS SECTIONS
- MT1 : Total cross section
Below 20 MeV, MT1 is adopted from JEFF-3.0. Above 20 MeV,
calculations from the spherical dispersive OMP were used.
- MT2 : Elastic scattering cross section
Below 20 MeV, MT2 is adopted from JEFF-3.0. Above 20 MeV, Mt2 is
obtained by subtracting the non-elastic cross section from the
total cross section.
- MT3 : Non-elastic cross section
Below 20 MeV, MT3 is adopted from JEFF-3.0. Above 20 MeV, Mt3 is
calculated with the optical model over the whole energy range.
- MT5 : (n,anything) cross section
Above 20 MeV, MT5 contains the total non-elastic cross section,
with which the information of MF6/MT5 can be combined to obtain
particle production cross sections and (double-)differential
cross sections.
##### MF4: ANGULAR DISTRIBUTIONS OF SECONDARY PARTICLES
- MT2 : Elastic angular distribution
The flag LTT=3 is used to indicate a switch at 20 MeV from a
Legendre representation to a tabulated representation. For
incident energies below 20 MeV, the data from JEFF-3.0 were
retained. For incident energies above 20 MeV, relative angular
distributions are tabulated on an angular grid.
##### MF6: PRODUCT ENERGY-ANGLE DISTRIBUTIONS
In MF6 we store all secondary energy, angle, and energy-angle
distributions, as well as all residual and photon production
cross sections.
- MT5 : (n,anything) yields and energy-angle distributions
For energies above 20 MeV, MT5 contains the production yields of
particles and residual products. It also contains the secondary
energy-angle distributions for all particles and photons. First,
the yields for neutrons are given for the whole energy range.
Next, on a secondary energy grid the relative emission spectra
are given together with the parameters for the Kalbach
systematics for angular distributions. Inelastic scattering
cross sections for discrete states have been broadened and added
to the continuum spectra. This procedure is repeated for protons,
deuterons, tritons, Helium-3, alpha particles and photons.
Finally, the residual production yields are given per final
product. All these yields and relative distributions can be
multiplied with the cross sections given in MF3/MT5 to get the
production cross sections and (double-)differential cross
sections.
***** F I L E C H E C K I N G A N D P R O C E S S I N G ****
This file has been checked successfully by the BNL checking
codes CHECKR-6.12, FIZCON-6.12 and PSYCHE-6.12 [dun01] and has
been processed successfully into an MCNP library by the
processing code NJOY99.81 [mac00].
*********************** R E F E R E N C E S **********************
[akk85] J.M. Akkermans and H. Gruppelaar, Phys. Lett. 157B, 95
(1985).
[ban96] Y. Bangjiao,F. Yangmei,W. Zhongmin,H. Rongdian, NSE 122,
136 (1996)
[chi89] L. Chi-chou,L. Han-lin,F. Pei-kou,M. Hung-chang,L. Yeh-Sha
Rep. INDC(CPR)-16 (1989)
[cor78] V.Corcalciuc,B.Holmqvist,A.Marcinkowski,G.A.Prokopets,
NPA 307,445 (1978)
[dic90] J.K.Dickens,C.Y.Fu,D.M.Hetrick,D.C.Larson,J.H.Todd,
Rep. ORNL-TM-11671 (1990)
[dun01] C. Dunford, ENDF Utility Codes Release 6.12, (2001).
[gar84] D.G. Gardner, in Neutron Radiative Capture, OECD/NEA
Series on Neutron Physics and Nuclear Data in Science and
Technology, eds. A. Michaudon et al., p. 62 (1984).
[gil65] A. Gilbert and A.G.W. Cameron, Can. J. Phys. 43, 1446
(1965).
[hau52] W. Hauser and H. Feshbach, Phys. Rev. 87, 366 (1952).
[ign75] A.V. Ignatyuk, G.N. Smirenkin, and A.S. Tishin, Sov. J.
Nucl. Phys. 21, no. 3, 255 (1975).
[kal88] C. Kalbach, Phys. Rev. C37, 2350 (1988).
[kal01] C. Kalbach, PRECO-2000: Exciton model pre-equilibrium
code with direct reactions, Duke University 2001,
www.nndc.bnl.gov/nndcscr/model-codes/preco-2000/.
[kon03] A.J. Koning and J.P. Delaroche, Nucl. Phys. A713, 231
(2003).
[kon04] A.J. Koning, S. Hilaire and M.C. Duijvestijn, unpublished
(2004).
[kon04b] A.J. Koning and M.C. Duijvestijn, to be published
(2004).
[kop90] J. Kopecky and M. Uhl, Phys. Rev. C42, 1941 (1990).
[koz78] JU.E.Kozyr',V.A.Pljujko,G.A.Prokopets, Yadernaya Fizika 28
16 (1978)
[lec03] F.R. Lecolley, in Workshop on Nuclear Data for the
Transmutation of Nuclear Waste, 2003, GSI-Darmstadt,
Germany (2003).
[mac00] R.E. Macfarlane, NJOY99 - Code system for producing
pointwise and multigroup neutron and photon cross
sections from ENDF/B Data, RSIC PSR-480 (2000).
[mad88] D.G. Madland, in Proceedings of a Specialists' Meeting on
Preequilibrium Reactions, Semmering, Austria,
February 10-12 1988, (OECD, Paris 1988), p. 103.
[mar83] A. Marcinkowski, R.W. Finlay, G. Randers-Pehrson,
C.E. Brient, R. Kurup, S. Mellema, A. Meigooni, and
R. Tailor,Nucl. Phys. A402, 220 (1983).
[mat92] S.Matsuyama,T.Ito,M.Baba,N.Ito,H.Iide,T.Okubo,
N.Hiarakawa, Rep. JAERI-M-92-027,309 (1992)
[ray94] J. Raynal, Notes on ECIS94, CEA Saclay Report
No. CEA-N-2772, 1994.
[rip98] Handbook for calculations of nuclear reaction data:
Reference Input Parameter Library, IAEA-TECDOC-1034
(1998).
[sly03] I. Slypen, N. Nica, A.J. Koning, E. Raeymackers,
S. Benck, J.P. Meulders, and V. Corcalciuc,
Journ. Phys. G, November 2003 (2003).
[sod95] D.Soda,S.Matsuyama,I.Masanobu,M.Baba,S.Iwasaki,
N.Hirakawa, Rep. JAERI-96-008,146, (1995)
[vil93] T.Vilaithong,D.Boonyawan,S.Konklong,W.Paisuwan,
S.Singkarat,Nucl.Instr. Meth. A332,561 (1993)
***************************** JEFF-3.0 ***********************
DATA TAKEN FROM :- EFF-3.1 (DIST-JAN01)
******************************************************************
AUTHORS AND RESPONSIBILITIES:
A. Trkov Institute Jozef Stefan, Ljubljana, Slovenia:
Overall file assembly, data thinning, formatting,
preliminary benchmarking.
S. Masetti(Contract researcher), R. Orsi, G.Reffo(retired),
Centro Nazionale Dati Nucleari, ENEA, Bologna, Italy:
Nuclear model calculations of energy/angle distribu-
tions, Quality assurance, gamma production data.
M. Herman Nulear Data Section, IAEA, Vienna, Austria:
Optical model parameters selection for EMPIRE code.
A. Koning, H. Gruppelaar, A. Hogenbirk, ECN Petten, Netherland:
Assembly of the EFF-3.0 starter file.
S. Tagesen, H. Vonach and V. Pronyaev, IRK Vienna, Austria:
Smooth cross sections evaluation above 850 keV.
F. Froehner(retired), KFK Karlsruhe, Germany:
Revised resolved resonance parameters.
EUROPEAN FUSION FILE VERSION 3.1
--------------------------------
The European Fusion File is a project of various European
laboratories and is sponsored by the European Fusion Programme
of the European Union.
Contact: Dr. H. Gruppelaar
ECN Nuclear Energy
Netherlands Energy Research Foundation ECN
P.O. Box 1
1755 ZG Petten
The Netherlands
HISTORY
98-11 CHANGES WITH RESPECT TO EFF-3.0 Rev.1
The starter file is the EFF-3.0 Revision 1 evaluation. The
differences with respect to this file are described:
1. The resolved resonance parameters, re-evaluated by Froehner
were substituted (F.H.Froehner, European Fusion Technology
Programme, NDB1-6, Dec.1995) by manually editing the data
from the listing in the report by MacMahon, JEF/DOC-631).
The energy range up to 850 keV was adopted consistently, to
correct the error in EFF-3.0 where the total cross section
in the range 850 to 862 keV was counted twice. To avoid
double counting of the self-shielding, the unresolved
resonance parameters were deleted.
2. Revised total cross section in the range 0.850 - 10 MeV
were taken from the Geel measurements /12/, scaled to the
Pronyaev evaluation /8,9/ over broad energy groups.
Piecewise linear smoothing was applied to reduce the number
of data points.
3. The Geel data /12/ are for NATURAL iron. Assuming the total
cross section data for Fe-54 from ENDF/B-VI Rev.3 and for
Fe-57, Fe-58 from EFF-2.4 (Froehner's recommendation,
JEF/DOC-650) the total cross section for Fe-56 was defined
such that in combination with the cross sections for the
other isotopes, the reconstructed total for the natural
mixture of isotopes reproduced the natural iron data. In
several energy intervals this correction to the total cross
section exceeded 40 %.
4. The cross section fluctuations modulating function was
recalculated, based on the new total cross section,
following the procedure previously described by Koning /10/.
The fluctuations were implemented only on the smooth
inelastic cross sections for the discrete levels and the
continuum of the Pronyaev evaluation.
5. The newly measured inelastic cross section for Fe-56 by
Dupont et.al [Geel, private communication] is stil
preliminary. After consultation with the author, the shape
of the measured cross section was imposed on the Pronyaev
et.al. evaluation by constructing a modulating function,
similarly like for the total cross section.
6. To ensure cross sections consistency, the total inelastic
cross section in the file was reconstructed by summing the
partials. Similarly, the elastic cross section was defined
as the difference between the new total and the reconstructed
non-elastic cross section.
7. Thinning of the elastic and discrete inelastic angular
distributions was performed, discarding energy points for
which the disctibutions could be reconstructed to within 1 %
by linear interpolation.
8. The energy-angle correlated outgoing particle distributions
were completely recalculated with the EMPIRE code /28/.
Besides the traditional approach to the direct reactions
(Optical Model) and to the compound nucleous reactions
(Hauser Feshbach), this code includes as a principal feature
the unified MultiStepDirect (MSD) plus the MultiStepCompound
(MSC) approach to the preequilibrium emission. In particular,
the Tamura et al. theory of MSD /29/ and the Nishioka et al.
theory for MSC /30/ are used. The model calculation performed,
indicates a structure in the inelastic scattering spectrum at
the incident neutron energy of about 14 MeV, arising directly
from a preequilibrium mechanism. This structure shows an
angular distribution which is not predicted by the Exciton
Model approach, but is partially supported by the experimental
data of Tagesen et al. /4/ and indirectly by an independent
ENDF/B-VI evaluation of the 2+ first excited level angular
distribution. Moreover, intergral experiments seems to be
sensitive to this stuctrure.
00-06 CHANGES WITH RESPECT TO EFF-3.1 Rev.1
(S. Tagesen, IRK Vienna)
In MF33 all subsections with reference to MT102 contained
one duplicated energy point at 862 keV. All those entries
and the according covariance matrix elements were removed
to avoid problems when using NJOY for processing.
MAIN FEATURES OF THE STARTER FILE EFF-3.0
Description is taken from the starter file but excluding
items 3 and 6, which are no longer relevant.
1. Rigourous adjustment procedure followed to match recent
experimental data, after careful corrections.
2. Covariance data based upon adjustments to experimental data.
4. Elastic angular distributions also in resolved resonance range
5. Covariances also in elastic angular distributions.
DATA PROCESSING FEATURES:
1. To produce an Ace file for the MCNP Monte Carlo transport
code, the version NJOY-97.45 (or higher) should be used.
BENCHMARKING:
The file has been benchmarked extensively using test cases
from the FENDL-2 Fusion Benchmarks collection:
"http://ripcnt01.iaea.org/nds/databases/fendl/FENDL.htm"
and from the Sinbad benchmarks database:
"http://www-rsicc.ornl.gov/BENCHMARKS.html".
The tests show that generally a marked improvement is
observed in the prediction of the measured benchmark
parameters. Formal documentation is inpreparation.
DESCRIPTION OF FILES:
(MF- MT)
1 - 451 History of evaluation, general information and
references
2 - 151 Resonance parameters (Reich-Moore formalism)
by Froehner are used from 1.E-5 eV upto 850 keV.
3 - 1 Adjusted total cross sections with experimental
fluctuation factors derived from Berthold et al /12/
and introduced by Trkov, following a similar procedure
as described previously by Koning /10/. A correction
for the presence of the minor isotopes is included.
3 - 2 Elastic scattering cross-sections is obtained by sub-
tracting the nonelastic from the total.
3 - 4 Total inelastic cross-sections is the sum of 3-51,
3-52,...3-82 and 3-91.
3 - 16 (n,2n) cross-section, adjusted by Pronyaev et al. /8/.
3 - 22 (n,na) + (n,an) cross-sections, adjusted by Pronyaev et
al. /8/.
3 - 28 (n,np) + (n,pn) cross-sections, adjusted by Pronyaev et
al. /8/.
3 - 51-82Inelasting scattering exciting discrete levels /8/.
Fluctuation factors as derived for the total cross
section data and introduced.
3 - 91 Inelastic scattering to the continuum, adjusted by
Pronyaev et al. /8/.
3 - 102 (n,g) cross-sections, adjusted by Pronyaev et al. /8/
3 - 103 (n,p) cross-sections; Sum of 3-600, .., 3-613 and 3-649.
3 - 105 (n,t) cross-sections.
3 - 106 (n,3-he) cross-sections.
3 - 107 (n,a) cross-sections; Sum of 3-800, ..,3-810 and 3-849.
3 - 600-613 (n,p) cross-sections exciting discrete levels /8/.
3 - 649 (n,p) cross-setions to continuum /8/.
3 - 800-810 (n,a) cross-sections exciting discrete levels /8/.
3 - 849 (n,a) cross-sections to continuum /8/.
4 - 2 Angular distributions of secondary neutrons for
elastic scattering from EFF-2.4, updated in the
resonance range by Pronyaev et al. /9/.
4 - 51-83 Angular distributions of secondary neutrons from
scattering to discrete levels, from EFF-2.4.
4 - 601-613 Angular distributions of protons exciting discrete
levels, from EFF-2.4.
4 - 801-810 Angular distributions of alpha's exciting discrete
levels, from EFF-2.4.
6 - 16 (n,2n) energy-angle distribution, EMPIRE calculation.
6 - 22 (n,na) + (n,an) energy-angle distribution, EMPIRE
calculation.
6 - 28 (n,np) + (n,pn) energy-angle distribution, EMPIRE
calculation.
6 - 91 Inelastic scattering exciting continuum, EMPIRE
calculation.
6 - 649 (n,p) energy-angle distribution to continuum, EMPIRE
calculation.
6 - 849 (n,a) energy-angle distribution to continuum, EMPIRE
calculation.
12 - 51-82 Transition probabilities for calculation of gamma-
ray spectra following (n,n') processes exciting
discrete levels, Herman and Reffo /11/.
12 - 102 Multiplicities for (n,g) reaction (below 1 MeV from
JEF-2 file smoothly joined at 1 MeV with MAURINA
calculation upto 20 MeV), from EFF-2.4.
12 - 601-613 The same for (n,p) process, Herman and Reffo /11/.
12 - 801-810 The same for (n,a) process, Herman and Reffo /11/.
14 - 51-82 Angular distribution of photons assumed isotropic
in CM system.
14 - 102 Angular distribution of photons assummed isotropic
in CM system.
14 - 601-613 Angular distribution of photons assumed isotropic
in CM system.
14 - 801-810 Angular distribution of photons assumed isotropic
in CM system.
15 - 102 Normalized energy distributions for the (n,g) reaction,
from EFF-2.4.
All covariance data described by Pronyaev et al. /8,9/.
33 - 1 Covariance matrix as NI subsubsection
33 - 2 Covariances as NC subsubsection
33 - 4 Covariances as NC subsubsection
33 - 16 Covariance matrix as NI subsubsection
33 - 22 Covariance matrix as NI subsubsection
33 - 28 Covariance matrix as NI subsubsection
33 - 51 Covariance matrix as NI subsubsection
33 - 52 Covariance matrix as NI subsubsection
33 - 53 Covariance matrix as NI subsubsection
33 - 54-57 Lumped to 851
33 - 58-64 Lumped to 852
33 - 65-82 Lumped to 853
33 - 102 Covariance matrix as NI subsubsection
33 - 103 Covariance matrix as NI subsubsection
33 - 104 Covariance matrix as NI subsubsection
33 - 105 Covariance matrix as NI subsubsection
33 - 106 Covariance matrix as NI subsubsection
33 - 107 Covariance matrix as NI subsubsection
33 - 851 Covariance-information for sum of reactions 54-57
33 - 852 Covariance-information for sum of reactions 58-64
33 - 853 Covariance-information for sum of reactions 65-82
34 - 2 Legendre coefficients A1-A3 covariances
*****************************************************************
DETAILED INFORMATION:
RESONANCE REGION:
Data from an evaluation by F. Froehner and F. Fabbri, revised
by Froehner.
Thermal region (included in resolved resonance region)
==============
The 2200 m/s cross sections for T = 0 were taken as follows:
Elastic scattering 2.59 b /14/,
Radiative capture 12.46 b /14/.
A bound level was introduced so that these values are reproduced
without file-3 ("smooth") correction.
Resolved resonance region up to 1st inelastic threshold, 850 keV
=========================
Formalism: 1-channel Reich-Moore (reduced R function)
Determination of the Reich-Moore parameters started from the
following compilations and evaluations:
0 - 862 keV Barn book Mughabghab+ 81 /14/,
0 - 300 keV Kedak-4 evaluation Froehner 77 /15/,
0 - 400 keV transm., capture, diff. scatter analysis
Perey+Perey 80 /16/.
These were updated and complemented with the following resonance
analyses:
450 - 900 keV Transm.,
Diff. scatter analysis Cierjacks+ 78 /17/,
2.5 - 862 keV Capture analysis Allen+ 76 /18/,
1 - 350 keV " " Corvi+ 83 /19/,
10 - 100 keV " " Kaeppeler+ 83 /20/.
Additional information on the 1.15 keV and the 27.7 keV resonance
was obtained from the following work:
1.15 keV NEANDC Task Force, see F. Perey 88 /21/,
Corvi+ 88 /22/,
Gayther+ 88 /23/;
Sowerby+Corvi 88 /24/
27.7 KEV Wisshak+ 81, 84 /25/ (rad. width)
Allen+ 80 /26/ ( " " )
Liou+ 79 /27/ (window)
Up to about 500 keV levels are fairly well resolved in capture
but above 500 keV capture data are less well resolved than
transmission data. Therefore capture peak areas of unresolved
multiplets are split and distributed among the separate
components seen in transmission. Spins and parities are taken
from Perey and Perey 80 below 400 keV, from Cierjacks 78 above.
Statistical analysis of the s-wave levels indicates for
0 - 862keV
Mean level spacing D = 22 +- 2 KEV,
Strength function S0 = (2.3 +- .7)/10000.
Statistics of p- and d-wave levels is uncertain especially above
400 keV due to increasing level overlap and uncertain spin-parity
assignments, only resonance areas (transmission dips, capture
peaks, even of unresolved multiplets) are to be taken seriously.
The contribution of distant levels is simulated by two fictitious
resonances far below and above the range 0 - 862 keV.
PHOTON PRODUCTION DATA:
Representation of photon production spectra:
1. Gamma-rays following binary reactions with particles in
the exit channel leading to discrete levels are stored
in MF=12,14 under MT= 51,52,...601,602,...801, 802,..811.
2. Gamma-rays from (n,gx) processes stored in MF=12,14,15
under MT=102.
3. Gamma-rays from (n,2n), (n,np), (,n,n-alpha), (n,n-cont.),
(n,p-cont.), (n,alpha-cont.) in MF6 under MT 16, 22, 28
91, 649 and 849.
3. Any remaining gamma-rays are not accounted for.
COVARIANCE DATA IN FILE 3:
Update by H. Vonach and S. Tagesen, I.R.K. Vienna, December 1993:
Approximate covariance information for the cross-sections in the
resonance range was added in file MF33. The given uncertainty
estimates are based on the following sources:
1. E(n)= 1.0e-5 eV to 1.0e+3 eV:
In this energy range the cross sections are tied to the
thermal and scattering cross-sections. Thus the uncertainties
of these cross-sections were used.
2. E(n)= 1.0e+3 eV to end of resonance range:
Uncertainties were estimated from:
2.1. Comparison of total and capture cross-sections reconstructed
from the resonance parameters with the recent accurate high
resolution measurements at Oak Ridge and Geel, both binned
into Vitamin-J structure.
2.2. Comparison of total and capture cross-sections pointwise
reconstructed from the resonance parameters given in
EFF-2.3, BROND-2.2, ENDF/B-VI, JEF-2.2 and JENDL-3.1 and
binned into Vitamin-J structure.
2.3. Discussion of uncertainties in absolute measurements of
capture cross-sections in the resonance range in recent
experiments papers.
3. E(n) in high-energy range.
Covariance data resulting from adjustment procedure /8,9/.
******************************************************************
REFERENCES:
/1/ M. Uhl, private communication.
/2/ JEF-2 evaluated file, made at ENEA-Bologna.
/3/ H. Gruppelaar, J. Kopecky, D. Nierop and M.Uhl,
"Evaluation of neutron cross-sections and photon-produc-
tion data for Cr-52 and Fe-56 isotopes in the energy
range 0 - 20 MeV", EFF-DOC (1990), ECN-REPORT, ECN-90.
/4/ H. Vonach, S. Tagesen, M. Wagner and A. Pavlik, Uncertainty
estimates for the fast neutron cross sections of the European
Fusion File EFF for 52Cr, 56Fe, 58Ni and 60Ni...., Final
report for contract No. 395-899-8/FU-D/NET, EFF-DOC 85 (1990)
/5/ H. Vonach, S. Tagesen, M. Wagner and V. Pronyaev, Evaluation
of the fast neutron cross sections of 56Fe including complete
covariance information, Physic Data 13-7, (1992)
/6/ S. Tagesen and H. Vonach, Uncertainty estimates for 52Cr,
56Fe, and 58,60Ni in the resonance range, EFF-DOC 254 (1993)
/7/ J. Kopecky, A. Hogenbirk, A.J. van der Kamp and D. Nierop,
European Fusion File EFF-2.4 - Final report on basic data
file, ECN--C-94-016, July 1994
/8/ V. Pronyaev, S. Tagesen, H. Vonach and S. Badikov,
Evaluations of the fast neutron cross sections of 52Cr and
56Fe including complete covariance information, Physics Data
13-8, (1995)
/9/ V. Pronyaev, S. Tagesen, H. Vonach and S. Badikov, Improve-
ment of the EFF-2 evaluations for 52Cr, 56Fe, 58 Ni and 60Ni,
Final Report for NET contract No. ERB 5000 CT 940031 (1995)
/10/ A.J. Koning, H. Gruppelaar and A. Hogenbirk, Fluctuation
factors in the EFF-3.0 file for 56Fe, EFF-DOC 381 (1995) and
ECN-R--95-018.
/11/ G. Reffo and M. Herman, Revision of the EFF-2.2 file for
26-Fe-56, EFF-DOC-252 (1994).
/12/ K. Berthold, C. Nazareth, G. Rohr and H. Weigmann, IRMM, Geel
private communication, data available from NEA Data Bank.
/13/ A. Hogenbirk, A.J. Koning and H. Gruppelaar, Validation of
the EFF-3.0 evaluation for Fe-56, EFF-DOC-382 (1995) and
ECN-R--95-019.
/14/ S.F. Mughabghab et al., Neutron cross sections, Acad. Press
(1981) Vol. 1, Part A.
/15/ F.H. Froehner, 1977 Geel meeting on Neutron data for struc-
tural mats., Pergamon (1979) p. 138
/16/ C.M. Perey and F.G. Perey, ORNL/TM-6405 (1980)
/17/ S. Cierjacks and I. Schouky, Nucl. Phys. and Nucl. Data,
Harwell (1978) p. 187
/18/ B.J. Allen et al., NP A269 (1976) 408
/19/ F. Corvi et al., Conf. Nucl. Data, Antwerp (1982) p. 131;
F. Corvi et al., IAEA Consult. Meet. on nucl. data for
Struct. mats., Vienna (1983), priv. comm.
/20/ F. Kaeppeler et al., NSE 84 (1983) 234
/21/ F. Perey et al., Conf. nucl. data, Mito (1988) p. 379
/22/ F. Corvi et al., NSE 93 (1988) 348, NIM A265 (1988) 475
/23/ D.B. Gayther et al., Conf. nucl. data, Mito (1988) p. 157
/24/ M.G. Sowerby, F. Corvi, " " " , Mito (1988) p. 37
/25/ Wisshak et al., NSE 77 (1981) 58; NSE 86 (1984) 168
/26/ B.J. Allen, J. Phys. G 6 (1980) 1173
/27/ H.I. Liou et al., NSE 70 (1979) 150
/28/ M. Herman and H. Lenske, EMPIRE Code (M.Herman, International
Atomic Energy Agency, Nuclear Data Section, Vienna, Austria,
Private communication, 1998).
/29/ T.Tamura, T.Udagawa, and H. Lenske, Phys. Rev. C26(1982)379.
/30/ H.Nishioka,J.J.M Verbaarschot, and H.A. Weidenmuller, and
S. Yoshida, Ann. Phys. 172(1986)67
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