ID 5
Type H - High priority request
Target 72-Hf-0
Reaction (n,g)
Quantity SIG - Cross section
Incident energy 0.5 eV - 5.0 keV
Accuracy 4 %
Field(s) Fission
Subfield LWR
Accepted date 16-Apr-2007
Status Archived
Latest review date 16-May-2018



Project (context)



In nuclear industry hafnium is used as neutron absorbing material to regulate the fission process. Interpretations of critical experiments with UOx fuel conducted by CEA in the AZUR zero-power reactors has shown systematic underestimation of the reactivity worth that may be attributed to an overestimated natural hafnium capture cross section in the epi-thermal energy range [1,2].


Requested accuracy can be found in the CEA Report "Correlations entre données nucleaires et experiences integrales a plaques, le cas du hafnium", Jean-Marc Palau, CEA-R-5843 (1997). The target accuracy on the effective capture integral has to be lower than 4%

Justification document

[1] David Bernard, "Determination des incertitudes liés aux grandeurs neutroniques d'interet des reacteurs a eau presurisee a plaques combustibles et application aux etudes de conformite", University Blaise Pascal, Clermont-Ferrand II, France (2001).
[2] G. Noguere, A. Courcelle, J.M. Palau, O.Litaize, "Low neutron energy cross sections of the hafnium isotopes", JEFDOC-1077.pdf, OECD-NEA, Issy-les-Moulineaux, France (2005).
[3] G. Noguere, A. Courcelle, P. Siegler, J.M. Palau, O. Litaize, "Revision of the resolved resonance range of the hafnium isotopes for JEFF-3.1", Technical note CEA Cadarache NT-SPRC/LEPH-05/2001 (2005).

Comment from requester

Neither the JENDL3.3 nor the JEFF3.1 libraries, that were recently issued, solve the problem. In fact, this was observed for JENDL3.3 before the JEFF3.1 file was constructed. As a result the JEFF3.1 file has been produced with this problem in mind taken into consideration the recent data from Trbovich et al. obtained at RPI [3]. Finally, a 400 pcm underestimation remains that is likely due to interfering isotopic contributions in the resolved energy region. New high resolution measurements appear needed, and would be particularly valuable if they can distinguish the contributions of different isotopes.

Review comment

Calculations on the AZUR configuration using the JEFF3.1 library give a Hf reactivity worth of about -300 pcm [2].

Entry status

Completed (as of SG-C review of May 2018) - The measurements performed at RPI [Trbovich:2009] and JRC-Geel [Ware:2010] allowed to significantly improve the Hf isotopes in JEFF, which now gives satisfactory results for reactivity worth due to Hf data [Noguere:2009].

Main recent references

Please report any missing information to hprlinfo@oecd-nea.org


  • A.K.M. Meaze et al. (G.N. Kim), Measurement of the Total Neutron Cross-Sections and the Resonance Parameters of Natural Hafnium at the Pohang Neutron Facility, J. Korean Phy. Soc. 46 (2005) 401, EXFOR 31689
  • K. Wisshak, et al., Fast neutron capture on the Hf isotopes: Cross sections, isomer production, and stellar aspects, PRC 73 (2006) 045807, EXFOR 22926
  • M.J. Trbovich, et al., Hafnium resonance parameter analysis using neutron capture and transmission experiments, NSE 161 (2009) 303, EXFOR 14239
  • T. Ware, Measurement and analysis of the resolved resonance cross sections of the natural hafnium isotopes, PhD thesis, University of Birmingham (2010); etheses.bham.ac.uk//id/eprint/807
  • M. Budak, et al., Experimental determination of effective resonance energies for 158Gd(n,g)159Gd and 179Hf(n,g)180mHf reactions, ANE 38 (2011) 2550


Additional file(s)

  1. jefdoc-1077 - 363.15 KB PDF