ID | 41 |
---|---|
Type | H - High priority request |
Target | 82-Pb-206 |
Reaction | (n,inl) |
Quantity | SIG - Cross section |
Incident energy | 0.5 MeV - 6 MeV |
Accuracy | 3-9 % |
Field(s) | Fission |
Subfield | Fast Reactors |
Accepted date | 15-Sep-2008 |
Status | Pending new evaluation or validation |
Latest review date | 28-Apr-2022 |
Requester
Prof. Massimo SALVATORES at CADARACHE, FR
Project (context)
CEA Cadarache
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).
This request is specific to the SFR and ADMAB lead-cooled systems.
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 | LFR | ADMAB | |||
λ=1 | λ≠1,a | λ=1 | λ≠1,a | ||
6.07 - 19.6 MeV | 18 | 7 | 9 | ||
2.23 - 6.07 MeV | 5 | 3 | 4 | ||
1.35 - 2.23 MeV | 14 | 5 | 7 | ||
0.498- 1.35 MeV | 11 | 3 | 4 |
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
Data have been taken at IRMM for using the (n,n’g)-technique. Experimental results have been included in a new evaluation. The experimental uncertainties are better than 5% in most of the energy range of interest and therefore the request is nearly met. Complementary data for the neutron emission spectrum (angular distribution) would be of interest.
Entry status
Pending new evaluation or validation (as of SG-C review of May 2018)
Main recent references
Please report any missing information to hprlinfo@oecd-nea.org
Experiments
Theory/Evaluation