CCFE is the fusion research arm of the United Kingdom Atomic Energy Authority
EAF-2010 – the best of a generation
Jean-Christophe Sublet, Lee Packer Euratom/CCFE Fusion Association
Culham Science Centre
and
Jura KopeckyJUKO Research
Overview of presentation
• Summary of modifications made from EAF-2007 release to EAF-2010
• Modifications to SAFEPAQ Cross Section Analysis Tool in support of SACS– Automatic generation of cross section data for
threshold reactions• Distinguishing threshold reactions• Plotting the skewness parameter of cross sections
for threshold reaction types
• Conclusions and the future
Main comments on EAF-2010• EAF-2010 is now
completed
• EAF-2010 will be the last of the generation of EAF files.
• It will be the most complete and improved version of the EAF files – the best of the generation
Activities: EAF-2007 to EAF-2010• Revision of all reaction channels supported by experimental
data using– visual comparison with EXFOR and updated Private EXFOR
(most recent data not yet included in EXFOR) databases – SACS analysis– C/E analysis at reference energies (0.0253 eV, 30 keV, 14.5 MeV
and RIs)
• Update and revision of capture data:– Extensive reviewing of all capture cross sections including the
revision of applied XS systematic (in particular 30 keV)– Results are in detail presented in:
RA Forrest, J Kopecky and AJ Koning, Revisions and improvements of neutron capture cross sections for EAF-2010 and validation of TALYS calculations, UKAEA 546, March 2008.
– Associated uncertainty data based on TALYS
Activities: EAF-2007 to EAF-2010 threshold reaction data
• Update and revision of threshold reaction data:– Revision of (n,d) and (n,n’p) XS to improve the agreement
with activation experiments for (n,d + n,n’p) cross sections– Revision of neutron emission channels (n,2n) and (n,3n) to
compensate for competition with (n,f)– Revision of XS based on the validation using integral
measurements. Reported in: RA Forrest et al., Validation of EASY-2007 using integral measurement, UKAEA 547, April 2008.
– J-Ch. Sublet et al., Decay power: a comprehensive experimental validation.
Activities: EAF-2007 to EAF-2010 uncertainties
• Update and revision of uncertainty file (a major action in this work):– Build from TENDl-2009 variance files– Revision of non-threshold (Score = 0) reactions: new error
factors introduced from XS systematics– Revision of non-threshold (Score > 0) reactions based on
comparison with experimental information– Revision of all non-threshold reactions: new semi-quantitative
approach used for error factors of 1/v and <100 keV regions, based on error propagation of (0.0253 eV) and RI with corresponding C/E values.
Activities: EAF-2007 to EAF-2010 Status - Assembling
• Assembling the EAF-2010 starter file– the starter file in a point-wise format has been
assembled using the EAF-2007 list of targets (816)– The action of modifications has been documented in
EAF-Doc-50, Revision and modifications for EAF-2010, by J. Kopecky (July 2009).
– Correctness of formats for group structure processing by SAFEPAQ-II has been tested.
– Addition a two new groups structure Red-616 and LANL-66
Activities: EAF-2007 to EAF-2010 Validation
• Validation of the EAF-2010:– A complete validation against all available differential measurements
• By SACS analysis of all major reactions with Q < 20 MeV • By C/E histogram analysis at major pertinent energies 0.0253 eV,
30 keV (n,g), 14.5 MeV and resonance integrals • The results are presented in EAF-Doc-51, Validation of EAF-2010,
by J. Kopecky (November 2009).
– A complete validation against all available integral measurements experiments (FNS, FNG, REZ, etc…)
– The validation reports will be produced with emphasis on different nuclear applications (High energy, inertial and tokamak fusion, reactor types).
• Reactions that tend to be most important for fusion applications are:
– (n,2n) – neutron multiplication
– (n,p) - produces hydrogen– (n,) - produces helium– (n,)– (n,n') – for isomeric states– However, other reaction
types can be important
data for 86 reaction types
Neutron-induced reactions
Statistical Analysis of Cross Sections (SACS)
•See, R A Forrest et al., Detailed analysis of (n,p) and (n,) cross sections in the EAF-2007 and TALYS generated libraries, Fus. Eng. Des. 2008.
Analysis options: Distinguish Threshold Reactions
Defining skewness for threshold reactions
LR
LRk
Skewness parameter,
SACS: Skewness parameter implementation
Statistical analysis of cross sections plots
• Extract (store) polynomial fit coefficients to each set of cross section statistical parameters (versus asymmetry) for a given reaction type.
EAF-2010 example of SACS
• The following questions needs some attention:– The competition of proton emission with the neutron channel, which is
manifested in (n,2n) vs (n,n’p), (n,p) and at higher energies (n,2p) depending on the binding energies of neutrons and protons. This influences the width and skewness of excitation curves for the above reaction channels. See examples for (n,p).
– This is the reason effort was given in the extension of SACS analysis.
Cross section parameters
Generate cross section data tool
Fitting options
Calculatedquantities
Generate cross section data tool: 7 reaction types enabled
Fitting options
•P3 – 3rd order polynomial, •P4 – 4th order polynomial•Exp – exponential fit•Parenthesis refers to points which the curve passes through
Error handling: all required trendlines are not stored
Error handling: all required trendlines are not stored
Error handling: user selects non-threshold reaction type for the selected target
Cubic fit to Eth, Elow and Emax
bAx
xbA-1 • Determine A-1 using Gauss-Jordan elimination method
and multiply by b matrix solution to cubic coefficients.
0
2
0
a
a
a
a
01E2E3
1EEE
1EEE
1EEE
max
max
4
3
2
1
max2max
max2max
3max
low2low
3low
th2th
3th
432
23
1 aEaEaEaE
Fits well over asymmetry range 0.01 – 0.25
Option 1: Quartic fit to Emax, Ehigh and E30; exponential fit to 30 and 60 MeV
3011Ea1110
30
max
max
9
8
7
6
5
30230
330
max2max
3max
30230
330
430
high2high
3high
4high
max2max
3max
4max
eaa
0
2
a
a
a
a
a
01E2E3E4
01E2E3E4
1EEEE
1EEEE
1EEEE
982
73
64
5 aEaEaEaEaE
Ea10
11eaE
Option 2: Cubic fit to Emax and Ehigh; exponential fit to Ehigh and 60 MeV
high10Ea109
max
8
7
6
5
high2high
max2max
high2high
3high
max2max
3max
eaa
0
2
0
a
a
a
a
01E2E3
01E2E3
1EEE
1EEE
Ea9
10eaE
872
63
5 aEaEaEaE
Options 4 and 5: Lorentzian fit to parameters
• Standard Lorentzian:
• Modified Lorentzian:Energy
0 10 20 30 40 50 60
0
1
2
3
4
5
Energy
0 10 20 30 40 50 60
0
1
2
3
4
5
6
7
32
2max
t1
aEaEE
EEaE
2
2
max
1
a
EE1
aE
Options 4 and 5: Modified Lorentzian
• Solve for a1, a2 and a3 using 3 conditions.
• Cannot directly use the Gauss-Jordan method of matrix inversion used previously, so solve this problem algebraically.
• Three unknowns require three conditions:
– Option 4: passing through Eh, Emax and d/dE=0 at Emax
– Option 5: passing through El, Emax and Eh
32
2max
t1
aEaEE
EEaE
Small improvements: omit systematic error bars
Concluding remarks for SAFEPAQ
• SAFEPAQ is a tool which can be used to plot and compare evaluations from all sources.
• It is continuously being improved: several new features have been added to enhance the plotting functionality and some tools to aid the evaluator(s)
• SAFEPAQ will continue to be used as an integral part of the evaluation process - future development of the tool will focus on tools to aid the merge of transport and activation data.
(n,p) for Final
Max
cro
ss s
ectio
n (b
)
Asymmetry (s)
1E-03
1E+01
1E-02
1E-01
1E+00
0.00 0.05 0.10 0.15 0.20 0.25
Integral C/E for Fe-54(n,p)Mn-54
C/E
Neutron Spectrum
C/E = 0.9504
C/E = 1.0436
C/E = 0.9722
C/E = 1.0833
C/E = 0.9669C/E = 0.9422
C/E = 1.0302
C/E = 0.9926C/E = 0.9949
C/E = 1.1032C/E = 1.1150
C/E = 1.1645
C/E = 0.9806
C/E = 1.0208
C/E = 1.0569
C/E = 1.2776
1.10
0.91
0.70
0.90
1.10
1.30
1.50
sneg_2 fng_f82h.asc cf252_flux_1 cf252_flux_1 cf252_flux_1 fzk_ss316 fng_vanad.asc rez_DF
sneg_1 fzk_2 fns_7hour cf252_flux_1 cf252_flux_1 fzk_ss316 fzk_1 fng_eurofer.asc
Y-89(n,2n)Y-88
Final
Cro
ss s
ection (
b)
Energy (eV)
0.0E+00
3.0E-01
6.0E-01
9.0E-01
1.2E+00
1.5E+00
1.0E+07 2.0E+07 3.0E+07 4.0E+07 5.0E+07 6.0E+07
SystmPAT79RI 99KGU00LAS75KYU79MOH84ANL87BRC81LAS75KOS81FEI89FEI89SAV98BRC02RI 99LAS75AUB76JAE93LAS77AEP89
Validation: SACS Validation: C/E
Cross sections
•816 targets (H-1 to Fm-257)•86 reaction types
•2,233 nuclides•Stables and isomeric states (T½ > 1s)
Decay data
EAF-2010
5096 important reactions
2265 major reactions
1728 reactions with any experimental data
66256 neutron induced reactions
470 reactions with integral data
EAF-2010
• The files are ready for distribution:
cross sections, uncertainty file, decay data, hazard indices,…
• The documentation is been finalized
• With updates on the FISPACT code it will form part of EASY-2010
• Validation & Verification tasks have already started
Concluding remarks
• EAF-2010 will be the last of a generation of EAF files• The approach has combined TALYS derived data with
careful and experienced evaluation using EXFOR and the SAFEPAQ evaluation/visualisation tool.
• It will be the most complete and improved version of the EAF generation
• For the future there is a strong desire to combine activation and transport calculations using complete and consistent data libraries (unique)
• Now its time to move towards this goal by taking the best data and approaches available