Version 2.03: 17 May 2006
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CONVERSION FACTORS
Unit Equivalent To
1 kt 10^12 calories
4.19x10^12 joules
4.19x10^19 ergs
2.62x10^31 eV
2.62x10^25 MeV
fission of 0.241 moles of material (1.45x10^23 nuclei)
fission of approx. 57 g of material
1.16x10^6 kilowatt-hrs
3.97x10^9 BTU
1 eV 1.602177 x 10^-12 erg
11606 degree K
1 Bar 10^5 pascals (nt/m^2)
10^6 dyne/cm^2
0.98687 atmospheres
14.5038 PSI
1 calorie 4.1868 J
Convenient Energy Content Approximations
Fission of U-233: 17.8 kt/kg
Fission of U-235: 17.6 kt/kg
Fission of Pu-239: 17.3 kt/kg
Fusion of pure deuterium: 82.2 kt/kg
Fusion of tritium and deuterium (50/50): 80.4 kt/kg
Fusion of lithium-6 deuteride: 64.0 kt/kg
Fusion of lithium-7 deuteride
Total conversion of matter to energy: 21.47 Mt/kg
Fission of 1.11 g U-235: 1 megawatt-day (thermal)
IMPORTANT UNITS OF MEASUREMENT
Quantity Measured Unit Symbol Formula
Microscopic Cross Section Barn b 10^-24 cm^2
Radioactivity Becquerel Bq 1 decay/sec
Curie Ci 3.7x10^10 decay/sec
Absorbed Radiation Dose Gray Gy 1 J/Kg
Rad None 100 erg/g (.01 J/Kg)
Biological Equivalent Dose Sievert Sv Grays*Q
Rem None Rads*RBE
Absorbed Gamma/X-Ray Dose Roentgen R 94 erg/g
Immediate Explosive Energy Kiloton kt 10^12 calories
Radiation Biological Effect None RBE
Radiation Quality Factor None Q
Pressure Bar None 10^5 pascals (nt/m^2)
PHYSICAL CONSTANTS
[All constants are exact to the precision given]
Quantity Symbol Value Unit
Speed of Light in Vacuum c 2.99792458 x 10^10 cm/sec
Planck Constant h 6.62608 x 10^-27 erg-sec
Avogadro Constant N_A 6.02214 x 10^23 atom/mole
Molar Gas Constant R 8.3145 x 10^7 erg/(mole K)
Boltzmann Constant k 1.3806 x 10^-16 erg/K
Stefan-Boltzmann Constant sigma 5.670 x 10^-5 erg/cm^2 K^4 sec
Perfect Gas Standard Volume V_0 2.2414 x 10^5 cm^3
Atomic Mass Constant m_0 1.66054 x 10^-24 g
m_0 9.31494 x 10^8 eV
| Isotope | Half-Life (years) |
Primary Decay Mode | Spontaneous Fission Rate - SF (F/sec/kg) |
Fission Cross Section - sigma (barns, fission spectrum avg) |
SF Neutron Multiplicity - nuSF (n/fission) |
Fission Spectrum Neutron Multiplicity - nuFS (n/fission) |
Critical Mass - Mc (kg) |
Decay Heat - Q (W/kg) |
Specific Activity (curies/kg) |
|---|---|---|---|---|---|---|---|---|---|
| Th-232 | 1.405 x 1010 | Alpha 4.083 MeV | <5 x 10-5 | 0.0785 | - | 2.16 | None | 2.654 x 10-6 | 1.097 x 10-4 |
| Pa-231 | 32,760 | Alpha 5.149 MeV | <5 | 0.834 | - | 2.457 | >188 | 1.442 | 47.23 |
| U-232 | 68.9 | Alpha 5.414 MeV | 2 x 10 -3 | 2.013 | 2 | 3.296 | >5 | 717.6 | 22,360 |
| U-233 | 159,200 | Alpha 4.909 MeV | - | 1.946 | - | 2.649 | 16 | 0.2804 | 9.636 |
| U-234 | 245,500 | Alpha 4.859 MeV | 3.9 | 1.223 | 1.8 | 2.578 | >41 | 0.1792 | 6.222 |
| U-235 | 7.038 x 108 | Alpha 4.679 MeV | 5.6 x 10-3 | 1.235 | 2.0 | 2.6055 | 48 | 5.994 x 10-5 | 2.161 x 10-3 |
| U-236 | 2.342 x 107 | Alpha 4.572 MeV | 2.30 | 0.594 | 1.8 | 2.526 | >167 | 1.753 x 10-3 | 0.06467 |
| U-238 | 4.468 x 109 | Alpha 4.270 MeV | 5.51 | 0.308 | 1.97 +- 0.07 | 2.6010 | None | 8.508 x 10-6 | 3.361 x 10-4 |
| Np-237 | 2.144 x 106 | Alpha 4.959 MeV | < 0.05 | 1.335 | 2 | 2.889 | 75-105 | 0.02068 | 0.7034 |
| Pu-238 | 87.7 | Alpha 5.593 MeV | 1.204 x 106 | 1.994 | 2.28 +- 0.10 | 3.148 | 9 | 5.678 x 105 | 17,120 |
| Pu-239 | 24,110 | Alpha 5.245 MeV | 10.1 | 1.800 | 2.9 | 3.1231 | 10.5 | 1.929 | 62.03 |
| Pu-240 | 65,640 | Alpha 5.256 MeV | 478,000 | 1.357 | 2.189 +- 0.026 | 3.061 | 40 | 7.07 | 227 |
| Pu-241 | 14.35 | Beta 0.021 MeV | <0.8 | 1.648 | - | 3.142 | 12 | 129.4 | 1.033 x 105 |
| Pu-242 | 373,300 | Alpha 4.984 MeV | 805,000 | 1.127 | 2.28 +- 0.13 | 3.070 | 95, range 75-100 | 0.1169 | 3.956 |
| Am-241 | 432.2 | Alpha 5.638 MeV | 500 | 1.378 | 2 | 3.457 | 83.5 | 114.7 | 3,431 |
| Cf-251 | 898 | Alpha 6.176 MeV | - | 2.430 | - | 4.560 | 1.94 | 58.05 | 1,586 |
This is subsection lists most isotopes of interest for direct, indirect, or theoretical nuclear weapon applications. Basic isotopes characteristics, and summary tables of significant neutron reaction cross sections are included.
The neutronic data is derived from the authoritative ENDF-VI evaluated nuclear data base compiled and maintained by the National Nuclear Data Center (NNDC) at the Brookhaven National Laboratory (BNL). The data listings below were prepared with the assistance of the Japan Atomic Energy Research Institute (JAERI).
Notes:
As can be seen where outside critical mass estimates are also available, this one-group calculation method consistently underestimates the true critical mass - primarily because it does not take into account the effects of inelastic scattering in softening the neutron spectrum. The one-group calculated critical mass estimates are thus lower bounds on the true value. Comparison between the one-group calculations and the actual values for the highly fissile isotopes for which good experimental data is available (U-233, U-235, Pu-239, and Pu-241) shows a consistent underestimate of 70-75% of the true value. For less fissile isotopes, where critical mass estimates have been offered by others (these are mostly calculated estimates also, but with more sophisticated models), the underestimates are more severe (at worst 22-29% of the 'true' value for Pu-242). This too is to be expected because the effects of inelastic scattering is relatively greater in less fissile materials. On the other hand, the estimates for extremely fissile transuranics like the californium isotopes should be quite good.
Sources:
H. C. Paxton and N. L. Pruvost, Critical Dimensions of Systems Containing 235-U, 239-Pu, and 233-U; 1986 Rev., LA-10860-MS, Los Alamos (July 1987), p. 96-104.
Hugh C. Paxton, "Fast Critical Experiments," Progress in Nuclear Energy Vol. 7 (1981), p. 154.
Samuel Glasstone and Leslie M. Redman, An Introduction to Nuclear Weapons, WASH-1037 Revised. U.S. Atomic Energy Commission, Division of Military Applications, June 1972, pg. 12.
Amory Lovins, "Nuclear Weapons and Power-Reactor Plutonium", Nature, Vol.283, 28 Feb 1980, pp. 817-823
Alexander De Volpi, Proliferation, Plutonium and Policy: Institutional and Technological Impediments to Nuclear Weapons Propagation, Pergamon (1979), pg. 86.
C. C. Byers, D. E. Hansen, J. J. Koelling, E. A. Plassmann, D. R. Smith, Reactivity Coefficients of Heavy Isotopes In LASL's-Fast Critical Assemblies, LA-UR-78-427, Los Alamos (June 1978), pg. 2.
Evaluation of nuclear criticality safety data and limits for actinides in transport, C4/TMR2001/200-1, IRSN (L'Institut de radioprotection et de sûreté nucléaire), 2001.
Neptunium criticality achieved, http://www.lanl.gov/news/index.php?fuseaction=home.story&story_id=1348
1-H-1
Lightest possible atom, and consequently the most efficient neutron moderator. Widely used in nuclear weapon structural materials (i.e. plastics). Due to moderating ability and light weight, used to harden weapons against outside neutron fluxes (especially in combination with Li-6).
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 20.81 20.78 692.0 -3 3.927
elastic 20.47 20.47 692.0 -3 3.926
capture 332.0 -3 294.2 -3 149.1 -3 29.83 -6 39.27 -6
---------------------------------------------------------------------------
1-H-2 (Deuterium)
Best nuclear reactor moderator due to high moderating efficiency and extremely low absorption cross section. A principal fusion fuel in thermonuclear weapons, can also be used for fusion boosting, and in neutron generators. Melting point 20.4 K, boiling point 23.67 K.
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 3.390 3.390 801.5 -3 2.537
elastic 3.389 3.390 624.3 -3 2.532
(n,2n) (E-thr = 3.339 MeV) 177.2 -3 5.276 -3
capture 550.0 -6 487.4 -6 286.3 -6 9.521 -6 7.076 -6
---------------------------------------------------------------------------
1-H-3 (Tritium)
A principal thermonuclear fuel, best used in conjunction with deuterium (the D+T reaction is the easiest by far to ignite, as well as one of the most energetic). It is produced in place by tritium breeding reactions in thermonuclear weapons. It can also manufactured and loaded into weapons (with deuterium) for use in fusion boosting of fission weapons, as the neutron source in neutron bombs and neutron generators for commercial or weapons use. Tritium is a pure beta emitter. Due to weak radiation emissions, it is used in safe luminescent displays. This nuclide is useful for thickness gauge of thin plastics.
2-He-3
This isotope is produced by the decay of tritium and so accumulates in fusion boosting reservoirs as an undesirable contaminant due to its high neutron absorption. It can be recycled to produce tritium by neutron bombardment. It is a valuable fusion fuel produced (and consumed) in the course of deuterium-deuterium fusion. Very rare in nature.
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 5.331 +3 4.743 +3 1.168 2.941
elastic 3.135 3.135 954.4 -3 2.121
nonelastic 5.328 +3 4.722 +3 2.381 +3 213.8 -3 819.6 -3
capture 54.01 -6 47.88 -6 246.9 -6 35.18 -6 39.24 -6
(n,p) 5.328 +3 4.722 +3 2.381 +3 139.7 -3 816.9 -3
(n,d) (E-thr = 4.362 MeV) 74.07 -3 2.647 -3
---------------------------------------------------------------------------
2-He-4
Most common natural isotope of helium. Widely used in industry as an inert gas. Produced as an end product of fusion reactions. This isotope has a zero cross section for all neutron reactions except scattering for neutron energies below 20 MeV.
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 759.3 -3 759.3 -3 1.052 3.685
elastic 759.3 -3 759.3 -3 1.052 3.685
---------------------------------------------------------------------------
3-Li-6
Natural lithium isotope used as a thermonuclear weapon fusion fuel, in the form of lithium deuteride, due to its production of tritium through the (n,t) reaction. The very high cross section of this reaction for thermalized neutrons, combined with the light weight of the Li-6 atom, make it useful in the form of lithium hydride for hardening of nuclear weapons against external neutron fluxes.
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 941.1 837.2 1.431 1.900
elastic 734.5 -3 735.2 -3 906.4 -3 1.422
nonelastic 940.4 836.5 427.5 525.0 -3 478.0 -3
inelastic (E-thr = 1.751 MeV) 412.0 -3 142.8 -3
(n,2n) (E-thr = 6.614 MeV) 78.05 -3 190.5 -6
capture 38.50 -3 34.11 -3 17.47 -3 82.11 -6 28.06 -6
(n,p) (E-thr = 3.185 MeV) 6.766 -3 4.264 -3
(n,t) 940.3 833.4 424.9 28.04 -3 330.7 -3
---------------------------------------------------------------------------
3-Li-7
Predominant isotope of natural lithium. Due to the large cross section for the (n,t) reaction at high neutron energies this isotope can breed substantial quantities of tritium in a fusion-driven chain reaction and thus serve as a fusion fuel. Although less efficient that Li-6 for this purpose, and not used in modern thermonuclear weapons it served this function in some early high yield weapons.
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 1.015 1.012 1.470 1.845
elastic 970.0 -3 971.7 -3 1.025 1.660
nonelastic 45.40 -3 40.38 -3 1.078 444.9 -3 184.8 -3
inelastic (E-thr = 0.546 MeV) 365.0 -3 184.7 -3
(n,2n) (E-thr = 8.300 MeV) 70.09 -3 38.53 -6
capture 45.40 -3 40.24 -3 20.43 -3 1.930 -6 6.903 -6
(n,d) (E-thr = 8.868 MeV) 9.763 -3 10.98 -6
total (n,t) (E-thr = 2.822 MeV) 302.9 -3 20.04 -3
---------------------------------------------------------------------------
4-Be-9
Beryllium is both an excellent neutron reflector and moderator, and is in addition very light. It has one of the highest neutron scattering cross sections per unit volume, and has very low neutron absorption. Beryllium is commonly used as a neutron reflector to make compact light-weight fission weapons. Beryllium also undergoes (n,2n) neutron multiplication reactions, which are not important for fission-spectrum neutons, but may have a significant role in fusion boosted systems. Beryllium can slo generate neutrons through Be-9(gamma,n)Be-8 and Be-9(a,n)C-12 reactions. When combined with an isotope that is a strong alpha-emitter but a weak gamma-emitter (usually Po-210), Be has been used in modulated neutron initiators for fission weapons. Pu-239/Be sources have been used as convenient laboratory neutron sources; Ra-226/Be and Am-241/Be neutron sources are useful for moisture gauges.
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 6.159 6.158 1.494 2.834
elastic 6.151 6.151 959.3 -3 2.673
nonelastic 7.600 -3 6.754 -3 1.164 534.5 -3 161.1 -3
inelastic (E-thr = 8.784 MeV) 22.90 -3 38.95 -6
(n,2n) (E-thr = 1.868 MeV) 269.1 -3 53.83 -3
(n,2na) (E-thr = 1.749 MeV) 17.49 -3 4.938 -3
(n,2n)to 1st (E-thr = 2.701 MeV) 168.6 -3 66.50 -3
(n,2n)to 2nd (E-thr = 7.561 MeV) 28.68 -3 133.4 -6
capture 7.600 -3 6.735 -3 3.419 -3 323.1 -9 1.156 -6
(n,p) (E-thr = 14.260 MeV) 20.25 -9
(n,d) (E-thr = 16.300 MeV) 32.68 -9
(n,t) (E-thr = 11.610 MeV) 18.36 -3 2.751 -6
(n,a) (E-thr = 0.670 MeV) 9.419 -3 35.65 -3
---------------------------------------------------------------------------
5-B-10
This natural isotope is the best absorber of fast neutrons, and an excellent absorber of slow neutrons. As a component of natural boron, it is commonly used as a neutron absorber (control rod or burnable poison) in nuclear reactors. The separated isotpe has been used to harden nuclear weapons against external neutron fluxes, and to reduce the neutron preheating of fusion stages by fission triggers in thermonuclear weapons. Use of B-10 has been proposed to create "clean" (low fallout and low neutron emission) thermonuclear weapons.
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REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 3.840 +3 3.415 +3 1.467 2.638
elastic 2.144 2.144 942.5 -3 2.062
nonelastic 3.838 +3 3.413 +3 1.726 +3 524.2 -3 575.3 -3
inelastic (E-thr = 0.791 MeV) 268.5 -3 70.84 -3
(n,2n) (E-thr = 8.980 MeV) 26.83 -3 33.22 -6
capture 500.0 -3 443.1 -3 224.9 -3 21.26 -6 76.03 -6
(n,p) 3.000 -3 2.659 -3 94.96 -3 37.51 -3 15.25 -3
(n,d) (E-thr = 4.801 MeV) 47.63 -3 1.249 -3
(n,a) 3.837 +3 3.400 +3 1.719 +3 48.95 -3 435.5 -3
(n,t2a) 12.00 -3 10.63 -3 305.2 -3 94.66 -3 52.28 -3
---------------------------------------------------------------------------
5-B-11
B-11 is the majority component of natural boron, and thus appears in boron mixtures used for nuclear applications where B-10 has not been separated.
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 5.050 5.050 1.415 2.425
elastic 5.045 5.045 934.9 -3 2.396
inelastic (E-thr = 2.320 MeV) 298.3 -3 28.81 -3
(n,2n) (E-thr = 12.510 MeV) 1.414 -3 496.7 -9
(n,na) (E-thr = 9.460 MeV) 101.0 -3 27.54 -6
(n,np) (E-thr = 12.260 MeV) 1.104 -3 211.0 -9
(n,n2a) (E-thr = 12.150 MeV) 17.96 -3 3.696 -6
(n,nd) (E-thr = 17.270 MeV) 1.335 -9
(n,nt) (E-thr = 12.250 MeV) 747.4 -6 169.8 -9
capture 5.075 -3 4.513 -3 2.542 -3 0.000 5.473 -6
(n,p) (E-thr = 11.710 MeV) 4.021 -3 579.7 -9
(n,d) (E-thr = 9.830 MeV) 9.200 -3 4.074 -6
(n,t) (E-thr = 10.430 MeV) 14.96 -3 3.443 -6
(n,a) (E-thr = 7.240 MeV) 31.38 -3 63.13 -6
---------------------------------------------------------------------------
27-Co-59
Although the concept of the enhanced fallout "cobalt bomb", in which radioactive Co-60 is produced by fusion neutrons, is well known this isotope is not known to have been seriously considered for weapons applications. The 5.26 year half-life of Co-60 is too long to be of real military interest, which favors more intense shorter term effects.
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 43.19 38.98 2.653 3.678
elastic 6.018 6.018 1.265 3.015
inelastic (E-thr = 1.118 MeV) 542.3 -3 655.5 -3
(n,2n) (E-thr = 10.630 MeV) 690.0 -3 180.0 -6
(n,na) (E-thr = 7.069 MeV) 1.765 -3 558.8 -9
(n,np) (E-thr = 7.496 MeV) 61.93 -3 56.52 -6
capture 37.18 32.96 75.51 1.121 -3 5.704 -3
(n,p) (E-thr = 0.796 MeV) 53.00 -3 1.484 -3
(n,d) (E-thr = 5.233 MeV) 5.673 -3 2.480 -6
(n,a) 0.000 0.000 20.24 -3 32.20 -3 165.1 -6
---------------------------------------------------------------------------
73-Ta-181
Comprising nearly all of natural tantalum, this isotope was studied for possible use in enhanced fallout radiation weapons by the U.S. in the 1950s. Compared with Co-60 the shorter half-life of Ta-182 (115 days vs 2.56 years) and the higher cross section for epithermal neutrons made Ta-181 a more desirable candidate for this use.
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 26.32 24.02 5.370 7.005
elastic 5.650 5.640 2.991 4.614
inelastic (E-thr = 0.006 MeV) 241.9 -3 2.295
(n,2n) (E-thr = 7.686 MeV) 2.133 5.149 -3
(n,3n) (E-thr = 14.300 MeV) 6.300 -6
(n,np) (E-thr = 5.968 MeV) 163.1 -6 55.01 -9
capture 20.67 18.38 660.0 205.5 -9 85.66 -3
(n,p) (E-thr = 0.242 MeV) 3.723 -3 2.305 -6
(n,a) 45.94 -6 47.65 -6 1.579 116.4 -6 3.588 -3
---------------------------------------------------------------------------
90-Th-232
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 21.11 20.23 5.740 7.634
elastic 13.71 13.70 2.683 4.579
inelastic (E-thr = 0.049 MeV) 726.0 -3 2.875
(n,2n) (E-thr = 6.465 MeV) 1.181 14.46 -3
(n,3n) (E-thr = 11.610 MeV) 800.0 -3 113.6 -6
fission 0.000 0.000 636.3 -3 350.0 -3 78.48 -3
capture 7.400 6.532 84.35 0.000 85.70 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
91-Pa-231
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 210.7 189.2 5.746 7.515
elastic 9.961 9.815 2.556 4.165
inelastic (E-thr = 0.009 MeV) 252.0 -3 2.231
(n,2n) (E-thr = 6.844 MeV) 724.0 -3 5.849 -3
(n,3n) (E-thr = 12.660 MeV) 134.0 -3 21.01 -6
fission 19.66 -3 16.99 -3 4.605 2.080 833.8 -3
capture 200.7 179.3 595.5 0.000 273.7 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
92-U-232
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 162.3 141.5 5.774 7.639
elastic 10.80 10.74 3.230 5.083
inelastic (E-thr = 0.048 MeV) 19.42 -3 509.2 -3
(n,2n) (E-thr = 7.286 MeV) 150.0 -3 484.1 -6
(n,3n) (E-thr = 13.210 MeV) 5.000 -3 562.0 -9
fission 76.66 66.42 363.8 2.370 2.013
capture 74.88 64.38 172.9 0.000 28.47 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
92-U-233
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 588.4 522.2 5.920 7.665
elastic 11.97 11.94 2.889 4.447
inelastic (E-thr = 0.041 MeV) 174.6 -3 1.198
(n,2n) (E-thr = 5.779 MeV) 406.9 -3 4.078 -3
(n,3n) (E-thr = 13.060 MeV) 2.049 -3 1.380 -6
fission 531.2 468.9 774.2 2.450 1.946
capture 45.25 41.34 138.4 13.71 -9 70.30 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
92-U-234
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 119.2 106.8 5.721 7.696
elastic 19.42 19.25 2.733 4.692
inelastic (E-thr = 0.044 MeV) 320.2 -3 1.557
(n,2n) (E-thr = 6.873 MeV) 473.0 -3 4.811 -3
(n,3n) (E-thr = 12.650 MeV) 127.0 -3 14.54 -6
fission 6.218 -3 5.536 -3 6.718 2.067 1.223
capture 99.75 87.53 631.3 25.77 -6 217.7 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
92-U-235
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 698.2 608.4 5.865 7.705
elastic 15.04 14.95 2.871 4.566
inelastic (E-thr = 0.000 MeV) 350.3 -3 1.804
(n,2n) (E-thr = 5.321 MeV) 542.9 -3 11.56 -3
(n,3n) (E-thr = 12.190 MeV) 41.79 -3 7.074 -6
fission 584.4 506.8 278.1 2.056 1.235
(n,4n) (E-thr = 17.970 MeV) 8.408 -9
capture 98.81 86.67 133.0 160.7 -9 89.07 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
92-U-236
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 13.69 13.09 5.748 7.735
elastic 8.336 8.330 2.757 4.769
inelastic (E-thr = 0.045 MeV) 326.0 -3 2.256
(n,2n) (E-thr = 6.578 MeV) 487.3 -3 7.645 -3
(n,3n) (E-thr = 11.900 MeV) 522.9 -3 66.34 -6
fission 61.29 -3 54.44 -3 7.764 1.659 594.0 -3
capture 5.295 4.703 345.6 366.6 -9 107.6 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
92-Uranium-238
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 12.09 11.77 5.805 7.786
elastic 9.360 9.356 2.704 4.804
inelastic (E-thr = 0.045 MeV) 698.3 -3 2.595
(n,2n) (E-thr = 6.179 MeV) 910.0 -3 12.07 -3
(n,3n) (E-thr = 11.330 MeV) 350.0 -3 61.90 -6
fission 11.77 -6 10.45 -6 2.020 1.136 308.4 -3
capture 2.717 2.414 278.1 1.943 -3 66.40 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
93-Np-237
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 192.1 171.2 5.539 7.799
elastic 27.46 27.14 2.606 4.965
inelastic (E-thr = 0.033 MeV) 105.6E-3 1.321
(n,2n) (E-thr = 6.657 MeV) 492.5E-3 3.120E-3
(n,3n) (E-thr = 12.370 MeV) 87.93E-3 14.05E-6
fission 22.49E-3 19.58E-3 7.058 2.247 1.335
capture 164.6 144.0 661.2 228.6E-9 173.4E-3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
94-Pu-238
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 586.7 501.1 6.876 8.829
elastic 28.54 27.85 3.584 6.014
inelastic (E-thr = 0.044 MeV) 1.155 -3 716.6 -3
(n,2n) (E-thr = 7.028 MeV) 514.7 -3 3.669 -3
(n,3n) (E-thr = 12.930 MeV) 54.45 -3 13.71 -6
fission 17.89 15.18 32.69 2.721 1.994
capture 540.3 458.0 153.6 5.861 -9 99.30 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
94-Pu-239
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 1.026 +3 980.2 5.990 7.712
elastic 7.968 7.787 2.984 4.394
inelastic (E-thr = 0.008 MeV) 366.3 -3 1.460
(n,2n) (E-thr = 5.680 MeV) 290.1 -3 4.045 -3
(n,3n) (E-thr = 12.710 MeV) 11.50 -3 2.762 -6
fission 747.4 698.3 302.5 2.338 1.800
(n,4n) (E-thr = 18.590 MeV) 176.2 -12
capture 270.3 274.2 181.5 7.930 -9 52.94 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
94-Pu-240
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 291.1 265.2 5.890 7.723
elastic 1.642 1.527 2.716 4.319
inelastic (E-thr = 0.043 MeV) 432.6 -3 1.950
(n,2n) (E-thr = 6.561 MeV) 373.1 -3 3.547 -3
(n,3n) (E-thr = 12.230 MeV) 113.5 -3 14.86 -6
fission 58.77 -3 53.41 -3 8.938 2.254 1.357
(n,4n) (E-thr = 19.260 MeV) 6.280 -9
capture 289.4 263.6 8.103 +3 800.0 -6 93.28 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
94-Pu-241
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 1.385 +3 1.275 +3 5.799 7.840
elastic 11.35 11.14 3.290 5.168
inelastic (E-thr = 0.042 MeV) 2.002 -3 884.0 -3
(n,2n) (E-thr = 5.262 MeV) 114.3 -3 21.37 -3
(n,3n) (E-thr = 11.820 MeV) 95.00 -3 18.00 -6
fission 1.012 +3 938.0 572.6 2.298 1.648
(n,4n) (E-thr = 17.500 MeV) 22.74 -9
capture 361.5 326.1 179.9 105.0 -9 118.2 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
94-Pu-242
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 27.11 25.12 5.954 7.934
elastic 8.318 8.294 2.922 4.810
inelastic (E-thr = 0.043 MeV) 279.0 -3 1.900
(n,2n) (E-thr = 6.336 MeV) 433.3 -3 6.667 -3
(n,3n) (E-thr = 11.600 MeV) 289.2 -3 43.45 -6
fission 2.557 -3 2.279 -3 5.577 2.027 1.127
(n,4n) (E-thr = 18.160 MeV) 133.1 -9
capture 18.79 16.82 1.130 +3 800.0 -6 87.87 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
95-Am-241
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 614.6 545.4 5.741 7.784
elastic 11.14 10.73 2.722 4.833
inelastic (E-thr = 0.041 MeV) 49.94 -3 1.340
(n,2n) (E-thr = 6.610 MeV) 262.4 -3 620.4 -6
(n,3n) (E-thr = 12.650 MeV) 46.74 -3 10.02 -6
fission 3.018 2.711 13.86 2.660 1.378
capture 600.4 532.0 1.305 +3 229.9 -9 229.6 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
95-Am-243
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 86.10 78.00 5.759 7.854
elastic 7.480 7.428 2.728 4.824
inelastic (E-thr = 0.042 MeV) 308.5 -3 1.754
(n,2n) (E-thr = 6.391 MeV) 360.5 -3 3.728 -3
(n,3n) (E-thr = 11.950 MeV) 221.1 -3 33.16 -6
fission 116.1 -3 103.3 -3 7.585 2.140 1.080
(n,4n) (E-thr = 18.570 MeV) 2.068 -9
capture 78.50 70.46 1.823 +3 230.7 -9 189.4 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
98-Cf-249
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 2.177 +3 1.869 +3 5.817 8.082
elastic 6.223 5.989 2.747 4.952
inelastic (E-thr = 0.063 MeV) 65.64 -6 1.249
(n,2n) (E-thr = 5.616 MeV) 662.0 -3 14.19 -3
(n,3n) (E-thr = 12.620 MeV) 118.0 -3 24.69 -6
fission 1.666 +3 1.430 +3 2.219 +3 2.290 1.741
(n,4n) (E-thr = 18.660 MeV) 3.046 -9
capture 504.5 433.6 694.9 328.2 -12 120.8 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
98-Cf-251
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 7.889 +3 6.712 +3 5.838 8.148
elastic 76.09 70.15 2.754 4.814
inelastic (E-thr = 0.025 MeV) 10.20 -3 862.9 -3
(n,2n) (E-thr = 5.132 MeV) 268.1 -3 12.34 -3
(n,3n) (E-thr = 11.780 MeV) 325.2 -3 44.33 -6
fission 4.935 +3 4.196 +3 2.774 +3 2.478 2.430
(n,4n) (E-thr = 17.400 MeV) 59.29 -9
capture 2.878 +3 2.446 +3 1.604 +3 11.11 -9 27.45 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)
98-Cf-252
---------------------------------------------------------------------------
REACTION 2200-m/s Maxw.Avg. Res.Integ 14-MeV Fiss.Avg.
(barns) (barns) (barns) (barns) (barns)
---------------------------------------------------------------------------
total 64.77 58.49 5.848 8.186
elastic 11.04 11.02 2.758 5.144
inelastic (E-thr = 0.046 MeV) 10.29 -3 731.5 -3
(n,2n) (E-thr = 6.195 MeV) 86.60 -3 4.930 -3
(n,3n) (E-thr = 11.330 MeV) 223.0 -3 35.17 -6
fission 33.03 29.20 110.7 2.770 2.251
(n,4n) (E-thr = 17.980 MeV) 11.66 -9
capture 20.71 18.27 47.34 185.6 -9 51.29 -3
---------------------------------------------------------------------------
Average neutron induced Nu_p (prompt neutrons/fission)