JEFF, Model calculations
Impact:
New double differential experimental data for the Fe(n,xn) reaction will allow a crucial test of the pre-equilibrium models underlying neutron transport libraries for spallation neutron sources. They will thereby enhance the confidence in neutron transport calculations for spallation neutron sources such as envisioned for accelerator driven systems.
Accuracy:
30% for the double-differential spectra
Justification document:
A global pre-equilibrium analysis from 7 to 200 MeV based on the optical model potential, A.J. Koning and M.C. Duijvestijn,
Nucl. Phys. A744, 15 (2004).
Comment from requester:
There are hundreds of (p,xp) and (p,xn) spectra in the 20-200 MeV range available, several (n,xp) spectra, but there are basically no
double-differential (n,xn) spectra available. The presence of such data would heavily constrain the pre-equilibrium model parameters and thereby result in a much better prediction of neutron-induced spectra in the entire 50-200 MeV range. Since high-energy spectra are rather structureless the choice of target is less essential.
Review comment:
Entry Status:
Completed (as of SG-C review of May 2018) - The experimental program performed at Uppsala [Sagrado:2011] combined with improvements in nuclear reaction models allow modern evaluations to address this request, see e.g. [Herman:2018].
Main references:
Please report any missing information to hprlinfo@oecd-nea.org
Experiments
- I.C. Sagrado Garcia et al., Neutron production in neutron-induced reactions at 96 MeV on 56Fe and 208Pb, PRC 84 (2011) 044619
Theory/Evaluation
- M. Herman et al., Evaluation of Neutron Reactions on Iron Isotopes for CIELO and ENDF/B-VIII.0, NDS 148 (2018) 214
Additional file attached:
Additional file attached:
| Request ID | 34 |
Type of the request | High Priority request |
| Target | Reaction and process | Incident Energy | Secondary energy or angle | Target uncertainty | Covariance |
| 26-FE-56 | (n,inl) SIG | 0.5 MeV-20 MeV | Emis spec. | See details | Y |
| Field | Subfield | Date Request created | Date Request accepted | Ongoing action |
| Fission | ADMAB and SFR | 04-APR-08 | 12-SEP-08 | Y |
Requester: Prof. Massimo SALVATORES at CADARACHE, FR
Email:
Project (context): NEA WPEC Subgroup 26
Impact:
Design phases of selected reactor and fuel cycle concepts require improved data and methods in order to reduce margins for both economical and safety reasons. A first indicative nuclear data target accuracy assessment was made within WPEC Subgroup 26 (SG-26). The assessment indicated a list of nuclear data priorities for each of the systems considered (ABTR, SFR, EPR, GFR, LFR, ADMAB, VHTR, EPR). These nuclear data priorities should all be addressed to meet target accuracy requirements for the integral parameters characterizing those systems (see the accompanying requests originating from SG-26).
Somewhat different requested accuracy is required to meet target accuracies for keff, peak power and void coefficient for the Accelerator-Driven Minor Actinides Burner (ADMAB) and for keff for the Sodium-cooled Fast Reactor in a TRU burning configuration, i.e., with a Conversion Ratio CR<1 (SFR). Details are provided in the OECD/NEA WPEC Subgroup 26 Final Report: "Uncertainty and Target Accuracy Assessment for Innovative Systems Using Recent Covariance Data Evaluations" (link to WPEC Subgroup 26 Report in PDF format, 6 Mb).
Accuracy:
Target accuracies are specified per system and per energy group when they are not met by the BOLNA estimate of the current (initial) uncertainties. The weighting factor λ is explained in detail in the accompanying document. Changes from the reference value of λ=1 show the the possible allowance for other target uncertainties. Two cases (A and B) are distinguished for λ≠1 (see Table 24 of the report).
| Energy Range | Initial versus target uncertainties (%) |
| Initial | ABTR | SFR | EFR | LFR | ADMAB |
| | λ=1 | λ≠1,a | λ≠1,b | λ=1 | λ≠1,a | λ≠1,b | λ=1 | λ≠1,a | λ=1 | λ≠1,a | λ=1 | λ≠1,a |
|
| 6.07 - 19.6 MeV | 13 | | | | 9 | 11 | 13 | | | | | | |
| 2.23 - 6.07 MeV | 7 | | | | 4 | 5 | 7 | | | | | 3 | 3 |
| 1.35 - 2.23 MeV | 25 | 6 | 7 | 10 | 3 | 4 | 7 | 7 | 7 | 4 | 6 | 2 | 2 |
| 0.498 - 1.35 MeV | 16 | 8 | 9 | 13 | 3 | 4 | 6 | 8 | 9 | 4 | 5 | 2 | 2 |
Justification document:
OECD/NEA WPEC Subgroup 26 Final Report: "Uncertainty and Target Accuracy Assessment for Innovative Systems Using Recent Covariance Data Evaluations" (link to WPEC Subgroup 26 Report in PDF format, 6 Mb).
Comment from requester:
Given the present state of knowledge the above target accuracies are very tight. However, any attempt that significantly contributes to reducing the present accuracy for this quantity is strongly encouraged. Any such attempt will significantly enhance the accuracy with which reactor integral parameters may be estimated and will therefore impact economic and safety margins.
Review comment:
Experimental work was recently completed at IRMM. The impact of the new experimental results is studied at CEA/Cadarache. Uncertainties below 5% will require a major further improvement.
Entry Status:
Work in progress (as of SG-C review of May 2018)
Main references:
Please report any missing information to hprlinfo@oecd-nea.org
Experiments
- R.O. Nelson et al., Cross-section standards for neutron-induced gamma-ray production in the MeV energy range, ND2004, AIP Conference Proceedings 769 (2004) 838, EXFOR 14118
- C.M. Castaneda et al., Gamma ray production cross sections from the bombardment of Mg, Al, Si, Ca and Fe with medium energy neutrons, NIM/B 260 (2007) 508, EXFOR 14151
- Z. Wang et al., Study on coincidence measurement for 56Fe(n,xng) reaction cross section, Atomic Energy Science and Technology 47 (2013) 2177, EXFOR 32720
- A. Negret et al., Cross-section measurements for the 56Fe(n,xng) reactions, PRC 90 (2014) 034602, EXFOR 23073
- R. Beyer et al., Inelastic scattering of fast neutrons from excited states in 56Fe, NP A 927 (2014) 41, EXFOR 23134
- A.M.Daskalakis et al., Quasi-differential elastic and inelastic neutron scattering from iron in the MeV energy range, Annals of Nuclear Energy 110 (2017) 603
- Ongoing work at University of Kentucky, cf. J.R. Vanhoy et al., Differential Cross Section Measurements at the University of Kentucky -- Adventures in Analysis, NEMEA-7, NEA Report NEA/NSC/DOC(2014)13, p.85
- related measurement by A. Negret, et al., Cross-section measurements for the 57Fe(n,ng)57Fe and 57Fe(n,2ng)56Fe reactions, PRC 96 (2017) 024620 - See section C which discusses the 847keV gamma production cross section in the 57Fe(n,2n) reaction. This contributes (above En=8-9 MeV) to the 847keV gamma production cross section in natFe(n,n') and therefore may represent a source of uncertainty for the 56Fe(n,inl) measurements performed with natFe targets.
- related measurement by A. Olacel, et al., Neutron inelastic scattering on 54Fe, Eur. Phys. J. A 54 (2018) 183
- E. Pirovano, et al., Cross section and neutron angular distribution measurements of neutron scattering on natural iron, PRC 99 (2019) 024601
Theory/Evaluation
Validation
- C. Jouanne, Sensitivity of the Shielding Benchmarks on Variance-covariance Data for Scattering Angular Distributions, Nuclear Data Sheets 118 (2014) 384
- I. Kodeli, A. Trkov, G. Zerovnik, Benchmark analysis of iron neutron cross-sections, Jozef Stefan Institute, Ljubljana, Slovenia, Report IJS-DP-11544 (2014)
- M. Salvatores, et al., Methods and Issues for the Combined Use of Integral Experiments and Covariance Data: Results of a NEA International Collaborative Study, Nuclear Data Sheets 118 (2014) 38
- G. Palmiotti, et al., Combined Use of Integral Experiments and Covariance Data, Nuclear Data Sheets 118 (2014) 596
- A. Shaw, et al., Validation of Continuous-Energy ENDF/B-VIII.0 16O, 56Fe, and 63,65Cu Cross Sections for Nuclear Criticality Safety Applications, Nuclear Science and Engineering 195 (2021) 412
Additional file attached:SG26-report.html
Additional file attached:
| Request ID | 51 |
Type of the request | Special Purpose Quantity |
| Target | Reaction and process | Incident Energy | Secondary energy or angle | Target uncertainty | Covariance |
| 26-FE-54 | (n,a) SIG/SPA | 252Cf(sf) | | 2-5 | Y |
| Field | Subfield | Date Request created | Date Request accepted | Ongoing action |
| Dosimetry | Fast fission, D-T fusion | 06-OCT-17 | 06-OCT-17 | |
Requester: Dr Stanislav SIMAKOV at KIT, GER
Email: intersurfen@gmail.com
Project (context): IRDFF project
Impact:
The International Reactor Dosimetry and Fusion File (IRDFF) aims at providing evaluated neutron dosimetry reactions validated for all applications related to fission reactors and fusion technology development [IAEA2017].
Accuracy:
2%-5%
Justification document:
Accurate cross sections as well as spectrum-averaged cross sections (SACS) in relevant and well-characterized neutron fields are essential for improvement and validation of the evaluated data [Simakov2017].
Comment from requester:
Measurements of the spectrum-averaged cross section are missing for validation purposes, especially for improvement of the prompt fission neutron spectrum at high energy. See Cf252U235_HighThreshold.pdf below.
References
- [IAEA2017] IAEA CRP on Testing and Improving the International Reactor Dosimetry and Fusion File (IRDFF),
http://www-nds.iaea.org/IRDFFtest/.
- [Simakov2017] S. Simakov, et al., “Proposals for new measurements for IRDFF community and HPRL”, September 2017.
Review comment:
Entry Status:
Work in progress (as of SG-C review of May 2018)
Main references:
Please report any missing information to hprlinfo@oecd-nea.org
Experiments
Theory/Evaluation
Validation
Additional file attached:Simakov2017.pdf
Additional file attached:Cf252U235_HighThreshold.pdf
| Request ID | 76 |
Type of the request | Special Purpose Quantity |
| Target | Reaction and process | Incident Energy | Secondary energy or angle | Target uncertainty | Covariance |
| 26-FE-54 | (n,2n) SIG/SPA | 252Cf(sf)-235U(n,f) | | 5-10 | Y |
| Field | Subfield | Date Request created | Date Request accepted | Ongoing action |
| Dosimetry | High-energy | 06-OCT-17 | 06-OCT-17 | |
Requester: Dr Stanislav SIMAKOV at KIT, GER
Email: intersurfen@gmail.com
Project (context): IRDFF project
Impact:
The International Reactor Dosimetry and Fusion File (IRDFF) aims at providing evaluated neutron dosimetry reactions validated for all applications related to fission reactors and fusion technology development [IAEA2017].
Accuracy:
5%-10%
Justification document:
Accurate cross sections as well as spectrum-averaged cross sections (SACS) in relevant and well-characterized neutron fields are essential for improvement and validation of the evaluated data [Simakov2017].
Following a recommendation from the IAEA Data Development Project on Neutron Standards [Pronyaev2013], the IRDFF project supports SACS measurements of high-threshold (above 10 MeV) dosimetry cross-sections in well-characterized 252Cf(sf) and 235U(nth,f) neutron fields in order to improve the cross sections and/or the high-energy part of the prompt fission neutron spectra.
Comment from requester:
Measurements of the spectrum-averaged cross section are missing for validation purposes and for improvement of the cross section and prompt fission neutron spectrum above 10 MeV. See Cf252U235_HighThreshold.pdf below.
References
- [IAEA2017] IAEA CRP on Testing and Improving the International Reactor Dosimetry and Fusion File (IRDFF),
http://www-nds.iaea.org/IRDFFtest/.
- [Simakov2017] S. Simakov, et al., “Proposals for new measurements for IRDFF community and HPRL”, September 2017.
- [Pronyaev2013] V.G. Pronyaev, A.D. Carlson and R. Capote Noy, “Toward a New Evaluation of Neutron Standards”, IAEA Technical Meeting, 8-12 July 2013, INDC(NDS)-0641.
Review comment:
Entry Status:
Work in progress (as of SG-C review of May 2018)
Main references:
Please report any missing information to hprlinfo@oecd-nea.org
Theory/Evaluation
Additional file attached:Simakov2017.pdf
Additional file attached:Cf252U235_HighThreshold.pdf
| Request ID | 81 |
Type of the request | Special Purpose Quantity |
| Target | Reaction and process | Incident Energy | Secondary energy or angle | Target uncertainty | Covariance |
| 26-FE-0 | (n,x)Mn-54 SIG | 15 MeV-100 MeV | | 5-10 | Y |
| Field | Subfield | Date Request created | Date Request accepted | Ongoing action |
| Dosimetry | High-energy | 06-OCT-17 | 06-OCT-17 | |
Requester: Dr Stanislav SIMAKOV at KIT, GER
Email: intersurfen@gmail.com
Project (context): IRDFF project
Impact:
The International Reactor Dosimetry and Fusion File (IRDFF) aims at providing evaluated neutron dosimetry reactions validated for all applications related to fission reactors and fusion technology development [IAEA2017].
Accuracy:
5%-10%
Justification document:
Accurate cross sections as well as spectrum-averaged cross sections (SACS) in relevant and well-characterized neutron fields are essential for improvement and validation of the evaluated data [Simakov2017].
Comment from requester:
The IRDFF project strives to evaluate, and eventually add to the library, high-threshold reactions with cross section plateaus located between 15/20 MeV and 100/150 MeV to meet the requirements of the accelerator-driven high-energy neutron sources. Note that it is important to know the cross section tail up to 100/150 MeV in order to allow the deconvolution of high-energy quasi-monoenergetic neutron source spectra.
References
- [IAEA2017] IAEA CRP on Testing and Improving the International Reactor Dosimetry and Fusion File (IRDFF),
http://www-nds.iaea.org/IRDFFtest/.
- [Simakov2017] S. Simakov, et al., “Proposals for new measurements for IRDFF community and HPRL”, September 2017.
Review comment:
Entry Status:
Work in progress (as of SG-C review of May 2018)
Main references:
Please report any missing information to hprlinfo@oecd-nea.org
Experiments
Theory/Evaluation
- K.I. Zolotarev, Evaluation of 50Cr(n,g)51Cr, 56Fe(n,x)54Mn, 57Fe(n,x)56Mn, and 68Zn(n,x)67Cu reaction cross sections for the IRDFF library, IAEA Report INDC(NDS)-0796 (2019)
- A. Trkov et al., IRDFF-II: A New Neutron Metrology Library, Nuclear Data Sheets 163 (2020) 1
Additional file attached:Simakov2017.pdf
Additional file attached:
| Request ID | 90 |
Type of the request | Special Purpose Quantity |
| Target | Reaction and process | Incident Energy | Secondary energy or angle | Target uncertainty | Covariance |
| 26-FE-54 | (n,2n) SIG | 15 MeV-100 MeV | | 5-10 | Y |
| Field | Subfield | Date Request created | Date Request accepted | Ongoing action |
| Dosimetry | High-energy | 06-OCT-17 | 06-OCT-17 | |
Requester: Dr Stanislav SIMAKOV at KIT, GER
Email: intersurfen@gmail.com
Project (context): IRDFF project
Impact:
The International Reactor Dosimetry and Fusion File (IRDFF) aims at providing evaluated neutron dosimetry reactions validated for all applications related to fission reactors and fusion technology development [IAEA2017].
Accuracy:
5%-10%
Justification document:
Accurate cross sections as well as spectrum-averaged cross sections (SACS) in relevant and well-characterized neutron fields are essential for improvement and validation of the evaluated data [Simakov2017].
Comment from requester:
The IRDFF project strives to evaluate, and eventually add to the library, high-threshold reactions with cross section plateaus located between 15/20 MeV and 100/150 MeV to meet the requirements of the accelerator-driven high-energy neutron sources. Note that it is important to know the cross section tail up to 100/150 MeV in order to allow the deconvolution of high-energy quasi-monoenergetic neutron source spectra.
References
- [IAEA2017] IAEA CRP on Testing and Improving the International Reactor Dosimetry and Fusion File (IRDFF),
http://www-nds.iaea.org/IRDFFtest/.
- [Simakov2017] S. Simakov, et al., “Proposals for new measurements for IRDFF community and HPRL”, September 2017.
Review comment:
Entry Status:
Work in progress (as of SG-C review of May 2018)
Main references:
Please report any missing information to hprlinfo@oecd-nea.org
Experiments
Theory/Evaluation
Additional file attached:Simakov2017.pdf
Additional file attached:Fe54n2n.pdf