NEA Nuclear Data High Priority Request List, HPRL

HPRL Main

High Priority Requests (HPR)

General Requests (GR)

Special Purpose Quantities (SPQ)

New Request

EG-HPRL
(SG-C)

Standard

Dosimetry



Request ID33 Type of the request High Priority request
TargetReaction and processIncident EnergySecondary energy or angleTarget uncertaintyCovariance
 94-PU-241 (n,g) SIG  0.1 eV-1.35 MeV  See details Y
FieldSubfieldCreated dateAccepted dateOngoing actionArchived Date
 Fission Fast Reactors (VHTR) 04-APR-08 12-SEP-08 Y

Send comment Send a comment on this request to NEA.

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).

Requested accuracy is required to meet target accuracies for keff and burnup for the Very High Temperature Reactor (VHTR). 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 RangeInitial versus target uncertainties (%)
  InitialSFR ADMABVHTRPWR
   λ=1 λ≠1,a λ≠1,b λ=1 λ=1 λ≠1,a λ=1 λ≠1,a
0.498 - 1.35 MeV 32 14 15 13 8
183 - 498 keV 21 11 11 10 7
0.10 - 0.54 eV 7 2 3 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.

Additional file attached: SG26-report.html

Review comment:
See appendix A of the attached report.

Entry Status:
Work in progress (as of SG-C review of May 2018)

Main recent references:
Please report any missing information to hprlinfo@oecd-nea.org

Theory/Evaluation

  • H. Derrien et al., Reevaluation and Validation of the 241Pu Resonance Parameters in the Energy Range Thermal to 20 eV, NSE 150 (2005) 109
  • Pu-241 evaluation was proposed to be part of INDEN (CIELO follow-up) initial program of work (as of Dec. 2017)

Validation