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EASY-2005 activation library and future plans. Robin Forrest Euratom/UKAEA Fusion Association Culham Science Centre. This work was funded jointly by the United Kingdom Engineering and Physical Sciences Research Council and by EURATOM. Outline. Introduction Need for n-induced data > 20 MeV
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EASY-2005 activation library and future plans Robin Forrest Euratom/UKAEA Fusion AssociationCulham Science Centre This work was funded jointly by the United Kingdom Engineering and Physical Sciences Research Council and by EURATOM
Outline • Introduction • Need for n-induced data > 20 MeV • Need for d-induced data • SAFEPAQ-II • Tool for creating activation libraries • EAF-2005 • The new libraries • Validation • New tools for library analysis • Deuteron-induced activation • Work towards EAF-2005.1 • Future work: EAF-2007 • Conclusions
Introduction • Understanding and predicting effect of neutrons on materials is fundamental to fusion technology • European Activation System (EASY) is the European tool • Previous versions such as EASY-2003 have an energy range < 20 MeV • Materials test facilities (IFMIF) use accelerators, high energy neutron tail upper energy limit is ~55 MeV • Need to extend EASY, has been carried out over 2 years, EASY-2005 is current version • IFMIF will use deuterons, there is a need for a library of deuteron-induced cross sections that can be used as part of EASY to enable activation studies
SAFEPAQ-II • Many data sources are used to assemble the EAF library • All data stored in relational databases • SAFEPAQ-II is the software tool that enables the databases to be: • Processed • Visualised • Validated • Output • Extended to treat sabove 20 MeV • Extended to treat d-induced data
New SAFEPAQ-II features • Able to read IEAF and TALYS libraries • New group structures with 211 and 351 energy groups • New uncertainty group between 20 and 60 MeV • MT numbers for summed reactions (MT >200) • e.g. (n,a+) = (n,a) + (n,n′h) + (n,pt) + (n,n′pd) + (n,2n2p) • Validation histograms showing (C/E) for the various reaction classes produced for any source library • For a library now have a choice of incoming particle (n or d) • SAFEPAQ-II: User Manual, R.A. Forrest, UKAEA FUS 454, Issue 6 (January 2005)
Experimental data • The use of experimental data is fundamental to SAFEPAQ-II • Internal database principally at thermal, 30 keV, 14,5 MeV • Complete EXFOR (2 CD-ROMs), relevant subset used for visualisation • Integral data, stored as ‘effective cross sections’ in specified neutron spectra • Another EXFOR CD-ROM containing d-induced data produced by NEA Data Bank • The data are used for: • Splitting cross sections into ground and isomeric contributions • Renormalisation • Validation
EAF-2005 cross sections • EAF-2005 requires data from 20 – 60 MeV • Calculated data produced by TALYS for data > 20 MeV • SAFEPAQ-II automatically smoothly joins TALYS-5 data at 20 MeV to existing data in EAF-2003 • For new reactions (generally with high thresholds) TALYS-5 data are used • A set of new MT numbers agreed with A Koning, allowing up to 8 particles to be emitted • 62,637 reactions (12,617 in EAF-2003) • 50 data sources • 86 different reaction types (23 in EAF-2003) • The European Activation File: EAF-2005 cross section library, R.A. Forrest, J. Kopecky and J-Ch Sublet, UKAEA FUS 515 (January 2005)
EAF-2005 decay data • New reactions will lead to the production of radio-nuclides not considered in the EAF-2003 decay data library • EAF-2005 contains 2,192 nuclides (278 new) • The new nuclides also require data on biological hazards, clearance and A2 • The European Activation File: EAF-2005 decay data library, R.A. Forrest, UKAEA FUS 516 (January 2005) • The European Activation File: EAF-2005 biological, clearance and transport libraries, R.A. Forrest, UKAEA FUS 517 (January 2005)
New reaction types (but standard ENDF) MT value Reaction • (n,2nd) 11 • (n,n´3a) 23 • (n,2n2a) 30 • (n,n'd2a) 35 • (n,n´t2a) 36 • (n,3np) 42 • (n,n´2p) 44 • (n,n´pa) 45 • (n,3a) 109 • (n,t2a) 113 • (n,d2a) 114 • (n,pd) 115 • (n,pt) 116 • (n,da) 117
New reaction types (non-standard) MT value Reaction • (n,5n) 152 • (n,6n) 153 • (n,2nt) 154 • (n,ta) 155 • (n,4np) 156 • (n,3nd) 157 • (n,n´da) 158 • (n,2npa) 159 • (n,7n) 160 • (n,8n) 161 • (n,5np) 162 • (n,6np) 163 • Plus 37 further reactions
Data for 27Al(n,p)27Mg Smooth join of EAF-2003 with TALYS-5
EAF-2005 • Builds on EAF-2004, improves quality of data • Further extension of SAFEPAQ-II • New differential measurements • New integral measurements • Use of TALYS-5 data • Use of LEA for improvement of (n,a) and (n,p) low energy data • Improvement of 2 and 4 group uncertainty data • The charged particle libraries required for SCPR all new – based on TALYS calculations, also extended to 60 MeV
New differential and integral data • Filatenkov has measured 14 reactions that were discrepant • Kopecky has searched EXFOR to find all data > 20 MeV • A new source of integral data identified: • S. Qaim et al., KfK Jülich in late seventies • New integral data for Y, Pb, Ta • Use of FZK and Řež integral data > 20 MeV
TALYS-5 and -5a data • A calculation for all targets using global parameters output in EAF format by A Koning • Corrects many problems identified in TALYS-4 • Better physics • ‘Smoother’ high energy data • Charged particle emission improved (still not perfect) • Is default choice for > 20 MeV data
TALYS-5 improvement – 58Ni(n,2n)57Ni Better fit to data Less ‘bumps’
New EXFOR data – 56Fe(n,p)56Mn EXFOR data > 20 MeV
New EXFOR data - 59Co(n,3n)57Co TALYS-5 in very good agreement with new high energy data Significant improvement over EAF-2004
Low Energy Approximation (LEA) • Represents the region below the effective threshold of (n,p) and (n,a) reactions with Q > 0 by resonance data and or pure 1/v (if no resonances exist) • Based on assumption that R = s(p)/s(g) or s(a)/s(g) is constant at low energies Pd-107s(a)/s(g) R Ag-107s(p)/s(g) En (keV)
LEA for 39K(n,a)36Cl EAF-2005 EAF-2003
New differential data – 80Se(n,p)80As EAF-2005 based on TALYS-5 renormalised to Filatenkov data EAF-2003 based on JEF-2.2
Integral data – 93Nb(n,a)90mY EAF-2003 EAF-2005 Integral C/E improved EAF-2003 1.0518, 1.1279 EAF-2005 1.0010, 1.0704
Validation of EASY-2005 • This is part of the current work • Details given in talk by Jura Kopecky • Work so far has identified some problems with EAF-2005 • Validation report will be produced at end of 2005 • Currently there are 448 reaction studied, of these 208 are validated • Based on C/E plots of integral data and plots of differential data as a function of energy
New SAFEPAQ-II tools • Verification and validation of very large EAF-2005 library is difficult – need for additional tools • Systematics show that cross sections at particular energies have a good correlation with parameters such as A or s = (N - Z) / A • Work on maximum cross sections by Manokhin for (n,2n) shows similar trend • SAFEPAQ-II can extract such data from EAF-2005 or one of the data sources (such as TALYS-5) and display a scatter plot against A, Z or s • Line of best fit can be added and reactions discrepant from the trend identified
Cross section analysis x-axis variable Data source Reaction Non-threshold reactions need to specify a minimum energy Plot y-axis variable Option to add a 2nd reaction e.g. (n,2n) + (n,n′p)
Maximum cross section - (n,2n) for EAF-2005 Trend Nb-91m(n,2n), what is wrong? Hf-178n(n,2n), what is wrong?
178Hf(n,2n) and 178mHf(n,2n) Hf-178(n,2n) data from TALYS-5a, but no data for the high spin Hf-178n isomer in TALYS-5a Use ADL-3, no renormalisation to systematics and data very small Need to improve
91mNb(n,2n)90gNb Error with first point in TALYS-5, should be 0 Need to improve
Width at half-maximum - (n,2n) for EAF-2005 Kr-76(n,2n), what is wrong?
76Kr(n,2n)75Kr Large width is due to shape of TALYS-5 data, need to improve?
Deuteron-induced data • IFMIF uses high energy d beams on a flowing lithium target • Corrosion products in the lithium means that reactions of d with a wide range of elements possible • Need to be able to calculate the d-induced activation • A d library (based on TALYS calculations) is being constructed, FISPACT will be modified so that the data can be used • The range of targets and reactions is similar to EAF-2005: • 60,688 reactions • 2,192 nuclides • Based on calculated data from TALYS • Very limited use of experimental data
58Ni(d,na)55Co Good agreement of EXFOR with TALYS calculation
63Cu(d,2n)63Zn Good agreement of EXFOR with TALYS calculation
51V(d,2n)51Cr Very poor agreement of EXFOR with TALYS calculation. More work needed!
FISPACT-2005 • Inventory code - calculates arisings of nuclides following neutron exposure • Developed over last 19 years for fusion applications • Features • External libraries of cross section and decay data • Elements hydrogen to fermium handled • Arbitrary irradiations (multiple pulses) • Arbitrary neutron spectrum • Gas production and isomers • Sensitivity and uncertainty calculations • Dominant nuclides and pathways • Fissionable actinides • Sequential charged particle reactions • Test version has ability to read a d-induced library
EASY-2005.1 • Obvious errors in the cross sections described above will be corrected • Implement ability to read d-induced library in FISPACT • Bug fixes in User Interface • Maintenance release at end of 2005 • Feedback from validation studies and physics improvements will be collected and implemented in the next version • Validation report for EASY-2005 distributed at end of 2005
EASY-2007 • EAF-2007 • implement feedback from integral validation • New TALYS-6 results • Will contain more complete d-induced library • Use detailed calculations on selected elements (Avrigeanu) • Use of EXFOR data or branching and renormalisation • Uncertainties? • Documentation
Activation handbook • Example of use of EAF-2003 data • All elements irradiated in fusion relevant neutron spectra • 544 pages of tabular and graphical data • Importance diagrams are spectrum independent • Results without running an inventory code • Handbook of Activation Data Calculated Using EASY-2003 M.R. Gilbert and R.A. Forrest, UKAEA report UKAEA FUS 509 (July 2004).(PDF file, size 8.6Mb) • Available for download
Conclusions • EAF-2005 completed and distributed to users • Validation and verification during 2005 • New SAFEPAQ-II tools to help in verification • Need for maintenance version (EAF-2005.1) to correct errors and implement d-induced activation • Validation and feedback to be used for EAF-2007 All EASY-2005 documentation, Validation reports and the Activation handbook can be downloaded from the web at http://www.fusion.org.uk/easy2005