A-5.
Actinide data: Thermal neutron cross sections, resonance integrals, and Westcott factors
 
 
     Nuclide       
 
  Type
 
  Cross Section
  σx [barn]
 
  Westcott Factor
  g
 
 
  Resonance Integral
  RI [barn]
 
  Source
 
  90-Th-232
  σ
  7.35 ± 0.03
  0.9982
  83.3 ± 1.5
   [1]
  92-U-233
  σ
  σ0f
  45.5 ± 0.7
  529.1 ± 1.2
  1.0495 ± 0.0223
  0.9955 ± 0.0015
  138 ± 6
  775 ± 17
   [2]
  
  92-U-234
  σ
  99.8 ± 1.3
  0.9903
  640 ± 20
   [1]
  92-U-235
  σ
  σ0f
  98.8 ± 0.8
  582.6 ± 1.1
  0.9956 ± 0.0016
  0.9771 ± 0.0008
  146 ± 6
  275 ± 5
   [3]
  
  92-U-236
  σ
  5.09 ± 0.10
  1.0027
  345 ± 15
   [4]
  92-U-237
  σγ
  443 ± 167
  0.9767
  1200 ± 200
   [5]
  92-U-238
  σ
  2.683 ± 0.012
  1.0009
  277 ± 3
   [6]
  93-Np-237
  σ
  175.9 ± 2.9
  0.982
  652 ± 24
   [1]
  93-Np-239
  σ
  68 ± 10
  1.0005
  455
   [7]
  94-Pu-238
  σ
  σ0f
  540 ± 7
  17.9 ± 0.4
  0.9563
  0.9562
  162 ± 15
  33 ± 5
   [1]
  
  94-Pu-239
  σ
  σ0f
  269.3 ± 2.9
  748.1 ± 2.0
  1.1369 ± 0.0119
  1.0553 ± 0.0013
  180 ± 20
  303 ± 10
   [2]
  
  94-Pu-240
  σ
  289.5 ± 1.4
  1.0264
  8452 ± 200
   [1]
  94-Pu-241
  σ
  σ0f
  362.1 ± 5.1
  1011.1 ± 6.2
  1.038
  1.046 ± 0.006
  162 ± 8
  570 ± 15
   [8]
  
  94-Pu-242
  σ
  18.5 ± 0.5
  1.0096
  1115 ± 40
   [1]
  95-Am-241
  σ
  σ0f
  σ0γ(g)
  σ0γ(m)
  587 ± 12
  3.20 ± 0.09
  533 ± 13
  54 ± 5
  1.051
  0.996
  
  
  1425 ± 100
  14.4 ± 1.0
  1230 ± 100
  195 ± 20
   [1]
  
  
  
  95-Am-242
  σf
  σγ
  2100 ± 200
  330 ± 50
  1.0502
  1.0471
  986
  186
   [7]
  
  95-Am-242m
  σγ
  σ0f
  1290 ± 300
  6200 ± 200
  1.100
  1.104
  211
  1570 ± 80
   [9]
  
  95-Am-243
  σf
  σ
  0.1983 ± 0.0043
  75.1 ± 1.8
  1.012
  1.014
  8.5 ± 0.5
  1820 ± 70
   [10]
  
  96-Cm-242
  σf
  σγ
  < 5
  16 ± 5
  0.9964
  0.9939
  12.9 ± 0.7
  110 ± 20
   [11]
  
  96-Cm-243
  σ
  σ0f
  130 ± 10
  617 ± 20
  1.005
  1.0054
  215 ± 20
  1570 ± 100
   [1]
  
  96-Cm-244
  σ
  σ0f
  15.2 ± 1.2
  1.04 ± 0.20
  0.999
  0.989
  655 ± 30
  12.5 ± 2.5
   [1]
  
 
Notation
 
σ0 Neutron cross section at 2200 m/s.
σ Neutron cross section measured in a Maxwellian spectrum.
σr Neutron cross section measured with reactor neutrons.
σc Neutron cross section calculated from resonance parameters or derived from equivalent data of the natural element.
σ(m) Neutron cross section leading to a metastable state of the product.
σ(g) Neutron cross section leading to the ground state of the product.
g Westcott factor: ratio of the Maxwellian averaged cross section σ to 2200 m/s cross section σ0 (g = σ/σ0 ). If the cross section varies as a function of 1/v, g = 1.0.
RI Infinite dilution resonance integral (including the 1/v contribution).
γ Subscript for radiative capture cross section.
f Subscript for fission cross section.
 
References
 

  ANR

S. F. Mughabghab, Atlas of Neutron Resonances, Resonance Parameters and Thermal Cross Sections, Z = 1 - 100, 5th Edition, Elsevier, Amsterdam, 2006.

  ENDF/B-VII

U.S. Evaluated Nuclear Data Library ENDF/B-VII β1,
http://www.nndc.bnl.gov/exfor7/endf00.htm, 2 October 2006;
see also M. B. Chadwick et al., ENDF/B-VII.0 : Next Generation Evaluated Nuclear Data Library for Nuclear Science and Technology, Nucl. Data Sheets 107 (2006) 2931.

  JEFF-3.1

Joint Evaluated Fission and Fusion File, Incident-neutron data,
http://www-nds.iaea.org/exfor/endf00.htm, 2 October 2006;
see also A. Koning, R. Forrest, M. Kellett, R. Mills, H. Henriksson, Y. Rugama, The JEFF-3.1 Nuclear Data Library, JEFF Report 21, OECD/NEA, Paris, France, 2006,
ISBN 92-64-02314-3.

  TRK-05

A. Trkov, G.L. Molnár, Zs. Révay, S.F. Mughabghab, R.B. Firestone, V.G. Pronyaev,
A.L. Nichols, M.C. Moxon, Revisiting the 238U Thermal Capture Cross Section and
Gamma-ray Emission Probabilities from 239Np Decay, Nucl. Sci. Eng. 150 (2005) 336.
 
Notes
 
[1] Data adopted from ANR; no uncertainty available for Westcott factors.

[2] Data adopted from ANR; gγ factor was calculated from fission and absorption cross-section data.

[3] All data adopted from ANR.

[4] Cross-section data and resonance integral adopted from ANR; Westcott factors without uncertainties calculated from the ENDF/B-VII library.

[5] Cross-section data and resonance integral adopted from ANR; Westcott factor without uncertainty calculated from the JEFF-3.1 library; RI = 296 barns in the ENDF/B-VII library.

[6] Thermal cross-section data adopted from TRK-05 (value of 2.680 ± 0.019 barns reported in ANR), and gγand resonance integral take from ANR; no uncertainty available for Westcott factor.

[7] Cross-section adopted from ANR; Westcott factors without uncertainties and resonance integrals calculated from the ENDF/B-VII library; a relative uncertainty of 20% is recommended.

[8] Data adopted from ANR; no uncertainty available for the gγ factor.

[9] Data adopted from ANR; gγ factor without uncertainty was calculated from the ENDF/B-VII library; resonance integral for radiative capture reported in ANR without uncertainty; a relative uncertainty of 20% is recommended.

[10] Data adopted from ANR; gf factor without uncertainty was calculated from the ENDF/B-VII library.

[11] σγ and resonance integrals adopted from ANR; σf < 5 barns is reported in ANR; values of 3 and 5 barns are given in the ENDF/B-VII and the JEFF-3.1 libraries, respectively; Westcott factors without uncertainties were calculated from the JEFF-3.1 library.

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