Section 12.0 Useful Tables (original) (raw)
Nuclear Weapons Frequently Asked Questions
Version 2.04: 5 April 2023
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12.0 Useful Tables
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 Th-232: 16.77 kt/kg
Fission of U-233: 17.89 kt/kg
Fission of U-235: 17.74 kt/kg
Fission of U-238: 17.27 kt/kg
Fission of Pu-239: 18.29 kt/kg
Fission of Pu-241: 18.10 kt/kg
Based on: Sher, R.; Beck, C. 1981. Fission Energy Release for 16 Fissioning Nuclides. NP-1771. Stanford University, Department of Mechanical Engineering, March 1981
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: TBD Total conversion of matter to energy: 21480.7643 kt/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 GraysQ Rem None RadsRBE 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
Fissionable/Fissile Isotope Properties
| 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 |
Isotope Properties and Neutron Cross Sections
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:
- The Maxwellian average cross sections are for a peak neutron energy distribution at 0.0253 eV (a room temperature thermal distribution).
- Molar volume is the minimum volume per mole for the densest phase at standard pressure and temperature (STP)
- SF = spontaneous fission
- Critical mass estimates for the fissile isotopes are given for bare spheres at the densest STP phase. Where available these estimates are from other sources and are based either on actual experimental measurement, or reasonably sophisticated numerical computations. All fissile isotopes also include for comparison critical mass estimates made by me, using an exact criticality solution with a one-group representation of neutronic properties. The one-group parameters are fission spectrum averages calculated from the ENDF-VI evaluated nuclear data base.
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 s�ret� nucl�aire), 2001.
Neptunium criticality achieved, http://www.lanl.gov/news/index.php?fuseaction=home.story&story_id=1348
Hydrogen
- Atomic number: 1
- Molar volume: 13.1 cm^3/mole (solid, 13 K)
- Density: 0.0763 (solid, 13 K, natural hydrogen)
- Melting point: 13.96 K (natural hydrogen)
- Boiling point: 20.39 K
1-H-1
- Atomic Mass: 1.007825032 +- 0.000000000 (amu)
- Excess Mass: 7288.969 +- 0.001 keV
- Binding Energy: 0.000 +- 0.000 keV
- Stable Isotope
- Atomic Percent Abundance: 99.985%
- >Magnetic Moment: 2.7928 nuclear magnetons
- Spin: 1/2+
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)
- Atomic Mass: 2.014101778 +- 0.000000000 (amu)
- Excess Mass: 13135.720 +- 0.001 keV
- Binding Energy: 2224.573 +- 0.002 keV
- Stable Isotope
- Atomic Percent Abundance: 0.015%
- Spin: 1+
- Magnetic Moment: 0.8574 nuclear magnetons
- Quadrupole Moment: 0.003 barns
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)
- Atomic Mass: 3.016049268 +- 0.000000001 (amu)
- Excess Mass: 14949.794 +- 0.001 keV
- Binding Energy: 8481.821 +- 0.004 keV
- Beta Decay Energy: B- 18.591 +- 0.001 keV
- Half Life: 12.33 years
Specific Activity: 9613 curie/g
Radioisotopic Power: 1.059 W/g
Primary Mode of Decay: Beta to He-3- Decay Energy: B- 18.591 +- 0.001 keV
- Magnetic Moment: 2.9789 nuclear magnetons
- Spin: 1/2+
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.
Helium
- Atomic number: 2
- Molar volume: 32.05 cm^3/mole (liquid, 4.125 K)
- Density: 0.1249 (liquid, 4.125 K, natural helium)
- Boiling point: 4.125 K
2-He-3
- Atomic Mass: 3.016029310 +- 0.000000001 (amu)
- Excess Mass: 14931.204 +- 0.001 keV
- Binding Energy: 7718.058 +- 0.002 keV
- Stable Isotope
- Atomic Percent Abundance: 0.000137%
- Magnetic Moment: -2.1276 nuclear magnetons
- Spin: 1/2+
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
- Atomic Mass: 4.002603250 +- 0.000000001 (amu)
- Excess Mass: 2424.911 +- 0.001 keV
- Binding Energy: 28295.673 +- 0.005 keV
- Beta Decay Energy: B- -22895.261 +- 212.132 keV
- Stable Isotope
- Atomic Percent Abundance: 99.999863%
- Magnetic Moment: 0.8220 nuclear magnetons
- Quadrupole Moment: -0.001 barns
- Spin: 0+
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
Lithium
- Atomic number: 3
- Molar volume: 13.0 cm^3/mole
- Density: 0.534
- Melting point: 180.54 C
- Boiling point: 1342 C
3-Li-6
- Atomic Mass: 6.015122281 +- 0.000000510 (amu)
- Excess Mass: 14086.312 +- 0.475 keV
- Binding Energy: 31994.564 +- 0.475 keV
- Beta Decay Energy: B- -4288.153 +- 5.448 keV
- Stable Isotope
- Atomic Percent Abundance: 7.42%
- Spin: 1+
- Magnetic Moment: 0.8220 nuclear magnetons
- Quadrupole Moment: -0.001 barns
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
- Atomic Mass: 7.016004049 +- 0.000000507 (amu)
- Excess Mass: 14907.673 +- 0.473 keV
- Binding Energy: 39244.526 +- 0.473 keV
- Beta Decay Energy: B- -861.815 +- 0.018 keV
- Stable Isotope
- Atomic Percent Abundance: 92.58%
- Spin: 3/2-
- Magnetic Moment: 3.2564 nuclear magnetons
- Quadrupole Moment: -0.040 barns
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
Beryllium
- Atomic number: 4
- Molar volume: 4.8775 cm^3/mole
- Density: 1.8477
- Melting point: 1287 C
- Boiling point: 2470 C
4-Be-9
- Atomic Mass: 9.012182135 +- 0.000000425 (amu)
- Excess Mass: 11347.584 +- 0.396 keV
- Binding Energy: 58164.907 +- 0.396 keV
- Beta Decay Energy: B- -1068.116 +- 0.899 keV
- Stable Isotope
- Atomic Percent Abundance: 100%
- Spin: 3/2-
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
Boron
- Atomic number: 5
- Molar volume: 4.39 cm^3/mole (alpha form, 25 C)
- Density: 2.46 (alpha form)
- Melting point: 2076 C
- Boiling point: 3900 C (estimated)
5-B-10
- Atomic Mass: 10.012937027 +- 0.000000397 (amu)
- Excess Mass: 12050.761 +- 0.370 keV
- Binding Energy: 64750.700 +- 0.370 keV
- Beta Decay Energy: B- -3647.807 +- 0.091 keV
- Stable Isotope
- Atomic Percent Abundance: 19.9%
- Spin: 3+
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.
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
* Atomic Mass: 11.009305466 +- 0.000000451 (amu)
* Excess Mass: 8667.984 +- 0.420 keV
* Binding Energy: 76204.800 +- 0.421 keV
* Beta Decay Energy: B- -1982.547 +- 0.854 keV
* Stable Isotope
* Atomic Percent Abundance: 80.1%
* Spin: 3/2-
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
Cobalt
- Atomic number: 27
- Molar volume: 6.61 cm^3/mole (25 C)
- Density: 8.92 (25 C)
- Melting point: 1493 C
- Boiling point: 2930 C
27-Co-59 - Atomic Mass: 58.9332002 +- 0.0000015 amu
- Excess Mass: -62223.609 +- 1.420 keV
- Binding Energy: 517308.113 +- 1.422 keV
- Beta Decay Energy: B- -1072.484 +- 0.561 keV
- Stable Isotope
- Atomic Percent Abundance: 100%
- Spin: 7/2-
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
Tantalum
- Atomic number: 73
- Molar volume: 10.84 cm^3/mole
- Density: 16.69
- Melting point: 2996 C
- Boiling point: 5429 C
73-Ta-181 - Atomic Mass: 180.9479963 +- 0.0000031 amu
- Excess Mass: -48441.085 +- 2.892 keV
- Binding Energy: 1452238.715 +- 2.903 keV
- Beta Decay Energy: B- -187.890 +- 4.549 keV
- Stable Isotope
- Atomic Percent Abundance: 99.988%
- Spin: 7/2+
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
Thorium
- Atomic number: 90
- Molar volume: 19.80 cm^3/mole (25 C)
- Density: 11.72 (25 C)
- Melting point: 1842 C (+- 30 C)
- Boiling point: 4820 C
90-Th-232 - Atomic Mass: 232.0380504 +- 0.0000022 amu
- Excess Mass: 35443.677 +- 2.036 keV
- Binding Energy: 1766691.409 +- 2.061 keV
- Beta Decay Energy: B- -494.958 +- 7.826 keV
- Atomic Percent Abundance: 100%
- Half Life: 1.405E10 Y
Specific Activity: 1.097E-7 curie/g
Radioisotopic Power: 2.654E-9 W/g
Primary Mode of Decay: Alpha to Ra-228 - Decay Energy: 4.083 MeV
Secondary Mode of Decay: SF Spontaneous fission
* Branch ratio: <1.0E-9 %
* SF rate (fissions/sec/g) = <4E-6
* Neutron emission rate (N/sec/g) = <6E-6
* Spin: 0+
* Critical mass: None
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)
* Incident neutron 1E-05 eV Nu_p = 1.896
* Incident neutron 1E+05 eV Nu_p = 1.910
* Incident neutron 1E+06 eV Nu_p = 2.040
* Incident neutron 4E+06 eV Nu_p = 2.472
* Incident neutron 2E+07 eV Nu_p = 4.774
* Incident neutron fission spectrum average Nu_p = 2.159
#### Protactinium
* Atomic number: 91
* Molar volume: 15.18 cm^3/mole (25 C)
* Density: 15.22 (Pa-231, 25 C)
* Melting point: 1568 - 1575 C
* Boiling point: unknown
91-Pa-231
* Atomic Mass: 231.0358789 +- 0.0000028 amu
* Excess Mass: 33420.973 +- 2.586 keV
* Binding Energy: 1759860.436 +- 2.605 keV
* Beta Decay Energy: B- -382.155 +- 3.220 keV
* Half Life: 32760 Y
Specific Activity: 0.04723 curie/g
Radioisotopic Power: 0.001442 W/g
Primary Mode of Decay: Alpha to Ac-227
* Decay Energy: 5.149 MeV
Secondary Mode of Decay: 24NEC
* Branch ratio: 13E-10 %
Tertiary Mode of Decay: Spontaneous fission
* Branch ratio: <=3E-10 %
* SF rate (fissions/sec/g) = <5E-3
* Neutron emission rate (N/sec/g) = <1E-2
* Spin: 3/2-
* Critical mass: Probably not fissile (C4/TMR2001/200-1), 188 kg (one-group calculation)
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)
* Incident neutron 1E-05 eV Nu_p = 2.274
* Incident neutron 1E+05 eV Nu_p = 2.285
* Incident neutron 1E+06 eV Nu_p = 2.381
* Incident neutron 4E+06 eV Nu_p = 2.702
* Incident neutron 2E+07 eV Nu_p = 4.420
* Incident neutron fission spectrum average Nu_p = 2.457
#### Uranium
* Atomic number: 92
* Molar volume: 12.56 cm^3/mole
* Density: 18.95 (alpha form, stable to 667.8 C)
* Melting point: 1132.2 C (+/- 0.8 C)
* Boiling point: 3818 degrees C
* specific heat 6.65 cal/mole/C (25 C)
* tensile strength 450 MPa
92-U-232
* Atomic Mass: 232.037146280 +- 0.000002857 (amu)
* Excess Mass: 34601.531 +- 2.662 keV
* Binding Energy: 1765968.847 +- 2.680 keV
* Beta Decay Energy: B- -2750.000 +- 100.000 keV
* Half Life: 68.9 Y
Specific Activity: 22.36 curie/g
Radioisotopic Power: 0.7176 W/g
Primary Mode of Decay: Alpha to Th-228
* Decay Energy: 5.414 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: = 2E-16 %
* SF rate (fissions/sec/g) = 2E-6
* Neutron emission rate (N/sec/g) = 4E-6
* Spin: 0+
* Critical mass: 3.57-3.70 kg (C4/TMR2001/200-1), 5.04 kg (one-group calculation)
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)
* Incident neutron 1E+00 eV Nu_p = 3.126
* Incident neutron 1E+05 eV Nu_p = 3.136
* Incident neutron 1E+06 eV Nu_p = 3.233
* Incident neutron 4E+06 eV Nu_p = 3.554
* Incident neutron 1.5E+07 eV Nu_p = 4.732
* Incident neutron fission spectrum average Nu_p = 3.296
92-U-233
* Atomic Mass: 233.039628196 +- 0.000003010 (amu)
* Excess Mass: 36913.421 +- 2.804 keV
* Binding Energy: 1771728.280 +- 2.821 keV
* Beta Decay Energy: B- -1028.513 +- 51.640 keV
* Half Life: 159200 Y
Specific Activity: 0.009636 curie/g
Radioisotopic Power: 0.0002804 W/g
Primary Mode of Decay: Alpha to Th-229
* Decay Energy: 4.909 MeV
* Spin: 5/2+
* Critical mass: 16 kg (LA-10860-MS; De Volpi; Hugh C. Paxton 1981), 11.63 kg (one-group calculation)
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)
* Incident neutron 2.53E-05 eV Nu_p = 2.487
* Incident neutron 1E+05 eV Nu_p = 2.487
* Incident neutron 1E+06 eV Nu_p = 2.565
* Incident neutron 2E+06 eV Nu_p = 2.680
* Incident neutron 1.4E+07 eV Nu_p = 4.223
* Incident neutron fission spectrum average Nu_p = 2.649
92-U-234
* Atomic Mass: 234.040945606 +- 0.000002122 (amu)
* Excess Mass: 38140.580 +- 1.976 keV
* Binding Energy: 1778572.444 +- 2.002 keV
* Beta Decay Energy: B- -1809.846 +- 8.321 keV
* Atomic Percent Abundance: 0.0055%
* Half Life: 245500 Y
Specific Activity: 0.006222 curie/g
Radioisotopic Power: 0.0001792 W/g
Primary Mode of Decay: Alpha to Th-230
* Decay Energy: 4.859 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: 1.7E-9 %
* SF rate (fissions/sec/g) = 3.9E-3
* Neutron emission rate (N/sec/g) = 7.2E-3
* Spin: 0+
* Critical mass: 145-149 kg (C4/TMR2001/200-1), 40.6 kg (one-group calculation)
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)
* Incident neutron 1E+00 eV Nu_p = 2.339
* Incident neutron 1E+05 eV Nu_p = 2.353
* Incident neutron 1E+06 eV Nu_p = 2.474
* Incident neutron 4E+06 eV Nu_p = 2.879
* Incident neutron 1.5E+07 eV Nu_p = 4.369
* Incident neutron fission spectrum average Nu_p = 2.578
92-U-235
* Atomic Mass: 235.043923062 +- 0.000002115 (amu)
* Excess Mass: 40914.062 +- 1.970 keV
* Binding Energy: 1783870.285 +- 1.996 keV
* Beta Decay Energy: B- -123.716 +- 0.869 keV
* Atomic Percent Abundance: 0.720%
* Spin: 7/2- 7
* Half Life: 7.038E8 Y
Specific Activity: 2.161E-6 curie/g
Radioisotopic Power: 5.994E-8 W/g
Primary Mode of Decay: Alpha to Th-231
* Decay Energy: 4.679 MeV
Primary Mode of Decay: Spontaneous fission
* Branch ratio: 7.0E-9%
* SF rate (fissions/sec/g) = 5.6E-6
* Neutron emission rate (N/sec/g) = 1.1E-5
* Meta state at 0.000 Mev
Half Life: ~25 M
Primary Mode of Decay: IT to U-235
* Spin: 1/2+
* Critical mass: 48 kg (LA-10860-MS; De Volpi), 33.4 kg (one-group calculation)
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)
* Incident neutron 2.53E-05 eV Nu_p = 2.4200
* Incident neutron 1E+05 eV Nu_p = 2.4158
* Incident neutron 1E+06 eV Nu_p = 2.5150
* Incident neutron 2E+06 eV Nu_p = 2.6303
* Incident neutron 4E+06 eV Nu_p = 2.8749
* Incident neutron 1.4E+07 eV Nu_p = 4.3857
* Incident neutron fission spectrum average Nu_p = 2.6055
92-U-236
* Atomic Mass: 236.045561897 +- 0.000002091 (amu)
* Excess Mass: 42440.627 +- 1.948 keV
* Binding Energy: 1790415.042 +- 1.974 keV
* Beta Decay Energy: B- -929.469 +- 50.427 keV
* Spin: 0+
* Half Life: 2.342E7 Y
Specific Activity: 6.467E-5 curie/g
Radioisotopic Power: 1.753E-6 W/g
Primary Mode of Decay: Alpha to Th-232
* Decay Energy: 4.572 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: 9.6E-8 %
* SF rate (fissions/sec/g) = 0.00230
* Neutron emission rate (N/sec/g) = 0.0041
* Critical mass: Not fissile (C4/TMR2001/200-1), 167 kg (one-group calculation)
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)
* Incident neutron 1E-03 eV Nu_p = 2.294
* Incident neutron 1E+05 eV Nu_p = 2.307
* Incident neutron 1E+06 eV Nu_p = 2.425
* Incident neutron 4E+06 eV Nu_p = 2.818
* Incident neutron 1.5E+07 eV Nu_p = 4.267
* Incident neutron fission spectrum average Nu_p = 2.526
92-Uranium-238
* Atomic Mass: 238.050782583 +- 0.000002126 (amu)
* Excess Mass: 47303.664 +- 1.980 keV
* Binding Energy: 1801694.651 +- 2.006 keV
* Beta Decay Energy: B- -147.065 +- 1.145 keV
* Atomic Percent Abundance: 99.2745%
* Half Life: 4.468E+9 Y
Specific Activity: 3.361E-7 curie/g
Radioisotopic Power: 8.508E^-9 W/g
Primary Mode of Decay: Alpha to Th-234
* Decay Energy: 4.270 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: 0.000044 %
* Average neutron yield (Nu)
Nu_prompt = 1.97 +- 0.07
* SF rate (fissions/sec/g) = 0.00551
* Neutron emission rate (N/sec/g) = 0.0108
* Spin: 0+
* Critical mass: none (not fissile)
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)
* Incident neutron 2.53000E-02 eV Nu_p = 2.4481
* Incident neutron 1E+05 eV Nu_p = 2.4552
* Incident neutron 1E+06 eV Nu_p = 2.5194
* Incident neutron 2.9E+06 eV Nu_p = 2.6548
* Incident neutron 5.15E+06 eV Nu_p = 3.0840
* Incident neutron 2E+07 eV Nu_p = 5.1819
* Incident neutron fission spectrum average Nu_p = 2.6010
#### Neptunium
* Atomic number: 93
* Molar volume: 11.59 cm^3/mole (25 C)
* Density: 20.45 (Np-237, 25 C)
* Melting point: 637 C
* Boiling point: 4000 C
93-Np-237
* Atomic Mass: 237.0481673 +- 0.0000021 amu
* Excess Mass: 44867.501 +- 1.961 keV
* Binding Energy: 1795277.138 +- 1.986 keV
* Beta Decay Energy: B- -220.318 +- 1.298 keV
* Half Life: 2.144E6 Y
Specific Activity: 7.034E-4 curie/g
Radioisotopic Power: 2.068E^-5 W/g
Primary Mode of Decay: Alpha to Pa-233
* Decay Energy: 4.959 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: <=2E-10 %
* SF rate (fissions/sec/g) = < 5.E-5
* Neutron emission rate (N/sec/g) = < 1.E-4
* Spin: 5/2+
* Critical mass: 60 kg (Neptunium criticality achieved), 63.6-81.9 kg (C4/TMR2001/200-1), 18.5 kg (one-group calculation)
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)
* Incident neutron 1E-05 eV Nu_p = 2.625
* Incident neutron 1E+05 eV Nu_p = 2.640
* Incident neutron 1E+06 eV Nu_p = 2.775
* Incident neutron 4E+06 eV Nu_p = 3.224
* Incident neutron 2E+07 eV Nu_p = 5.521
* Incident neutron fission spectrum average Nu_p = 2.889
#### Plutonium
* Atomic number: 94
* Molar volume: 12.061 cm^3/mole
* Density: 19.816 (20 C)
* Melting point: 639.5
* Boiling point: 3230 C
94-Pu-238
* Atomic Mass: 238.0495534 +- 0.0000021 amu
* Excess Mass: 46158.688 +- 1.982 keV
* Binding Energy: 1801274.921 +- 2.008 keV
* Beta Decay Energy: B- -2258.350 +- 50.688 keV
* Half Life: 87.7 Y
Specific Activity: 17.12 curie/g
Radioisotopic Power: 0.5678 W/g
Primary Mode of Decay: Alpha to U-234
* Decay Energy: 5.593 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: 1.9E-7 %
* Average neutron yield (Nu)
Nu_prompt = 2.28 +- 0.10
* SF rate (fissions/sec/g) = 1204.
* Neutron emission rate (N/sec/g) = 2745.
* Spin: 0+
* Critical mass: 12 kg (LA-UR-78-427), 8.95-9.49 kg (C4/TMR2001/200-1), 9 kg (Lovins), 5.26 kg (one-group calculation)
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)
* Incident neutron 1E-05 eV Nu_p = 2.891
* Incident neutron 1E+05 eV Nu_p = 2.906
* Incident neutron 1E+06 eV Nu_p = 3.039
* Incident neutron 4E+06 eV Nu_p = 3.483
* Incident neutron 1.4E+07 eV Nu_p = 4.964
* Incident neutron fission spectrum average Nu_p = 3.148
94-Pu-239
* Atomic Mass: 239.0521565 +- 0.0000021 amu
* Excess Mass: 48583.478 +- 1.971 keV
* Binding Energy: 1806921.454 +- 1.998 keV
* Beta Decay Energy: B- -802.912 +- 2.011 keV
* Half Life: 24110 Y
Specific Activity: 0.06203 curie/g
Radioisotopic Power: 0.001929 W/g
Primary Mode of Decay: Alpha to U-235
* Decay Energy: 5.245 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: 3E-10 %
* Average neutron yield (Nu)
Nu_prompt =
* SF rate (fissions/sec/g) = 7.E-3
* Neutron emission rate (N/sec/g) = 2.E-2
* Spin: 1/2+
* Critical mass: 10.5 kg (LA-10860-MS, WASH-1037 Rev., p. 12), 10.0-10.3 kg (C4/TMR2001/200-1), 7.42 kg (one-group calculation)
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)
* Incident neutron 2.53E-02 eV Nu_p = 2.8725
* Incident neutron 1E+05 eV Nu_p = 2.8976
* Incident neutron 1E+06 eV Nu_p = 3.0107
* Incident neutron 4E+06 eV Nu_p = 3.4456
* Incident neutron 1.4E+07 eV Nu_p = 4.9397
* Incident neutron fission spectrum average Nu_p = 3.1231
94-Pu-240
* Atomic Mass: 240.0538075 +- 0.0000021 amu
* Excess Mass: 50121.319 +- 1.947 keV
* Binding Energy: 1813454.935 +- 1.974 keV
* Beta Decay Energy: B- -1378.952 +- 13.790 keV
* Half Life: 6564 Y
Specific Activity: 0.227 curie/g
Radioisotopic Power: 0.00707 W/g
Primary Mode of Decay: Alpha to U-236
* Decay Energy: 5.256 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: 5.7E-6 %
* Average neutron yield (Nu)
Nu_prompt = 2.189 +- 0.026
* SF rate (fissions/sec/g) = 478.
* Neutron emission rate (N/sec/g) = 1047.
* Spin: 0+
* Critical mass: 35.7 kg (C4/TMR2001/200-1), 40 kg (Lovins; De Volpi), 15.2 kg (one-group calculation)
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)
* Incident neutron 1E-05 eV Nu_p = 2.794
* Incident neutron 4E+06 eV Nu_p = 3.402
* Incident neutron 1.4E+07 eV Nu_p = 4.922
* Incident neutron fission spectrum average Nu_p = 3.061
94-Pu-241
* Atomic Mass: 241.0568453 +- 0.0000021 amu
* Excess Mass: 52951.039 +- 1.948 keV
* Binding Energy: 1818696.538 +- 1.975 keV
* Beta Decay Energy: B- 20.815 +- 0.199 keV
* Spin: 5/2+
* Half Life: 14.35 Y
Specific Activity: 103.3 curie/g
Radioisotopic Power: 0.01287 W/g
Primary Mode of Decay: Beta to Am-241
* Decay Energy: 0.021 MeV
Secondary Mode of Decay: Alpha to U-237
* Branch ratio: 0.0025 %
* Decay Energy: 5.140 MeV
Tertiary Mode of Decay: Spontaneous fission
* Branch ratio: <2.E-14 %
* SF rate (fissions/sec/g) = <8.E-4
* Spin: 5/2+
* Critical mass: 12.3-13.0 kg (C4/TMR2001/200-1), 12 kg (Lovins; De Volpi), 9.03 kg (one-group calculation)
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)
* Incident neutron 1E-05 eV Nu_p = 2.930
* Incident neutron 1E+05 eV Nu_p = 2.930
* Incident neutron 1E+06 eV Nu_p = 3.013
* Incident neutron 4E+06 eV Nu_p = 3.490
* Incident neutron 2E+07 eV Nu_p = 5.963
* Incident neutron fission spectrum average Nu_p = 3.142
94-Pu-242
* Atomic Mass: 242.0587368 +- 0.0000021 amu
* Excess Mass: 54713.012 +- 1.966 keV
* Binding Energy: 1825005.887 +- 1.993 keV
* Beta Decay Energy: B- -750.963 +- 0.718 keV
* Half Life: 3.733E5 Y
Specific Activity: 0.003956 curie/g
Radioisotopic Power: 0.0001169 W/g
Primary Mode of Decay: Alpha to U-238
* Decay Energy: 4.984 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: 0.00055 %
* Average neutron yield (Nu)
Nu_prompt = 2.28 +- 0.13
* SF rate (fissions/sec/g) = 805.
* Neutron emission rate (N/sec/g) = 1840
* Spin: 0+
* Critical mass: 85.6 kg (C4/TMR2001/200-1), 90 kg (LA-UR-78-427), 95 kg (Lovins), range 75-100 kg (De Volpi); 22.1 kg (one-group calculation)
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)
* Incident neutron 1E-05 eV Nu_p = 2.790
* Incident neutron 1E+05 eV Nu_p = 2.806
* Incident neutron 1E+06 eV Nu_p = 2.948
* Incident neutron 4E+06 eV Nu_p = 3.421
* Incident neutron 2E+07 eV Nu_p = 5.950
* Incident neutron fission spectrum average Nu_p = 3.070
#### Americium
* Atomic number: 95
* Molar volume: 17.63 cm^3/mole
* Density: 13.67 (Am-241, 25 C)
* Melting point: 1175 C
* Boiling point: 2607 C
95-Am-241
* Atomic Mass: 241.0568229 +- 0.0000021 amu
* Excess Mass: 52930.224 +- 1.957 keV
* Binding Energy: 1817935.000 +- 1.984 keV
* Beta Decay Energy: B- -767.357 +- 1.173 keV
* Half Life: 432.2 Y
Specific Activity: 3.431 curie/g
Radioisotopic Power: 0.1147 W/g
Primary Mode of Decay: Alpha to Np-237
* Decay Energy: 5.638 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: 4E-10 %
* SF rate (fissions/sec/g) = 0.5
* Neutron emission rate (N/sec/g) = 1.
* Spin: 5/2-
* Critical mass: 58 kg (LA-UR-78-427), 57.6-75.6 kg (C4/TMR2001/200-1), 83.5 kg (Lovins; density adjusted), 23 kg (one-group calculation)
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)
* Incident neutron 1E-05 eV Nu_p = 3.235
* Incident neutron 2E+05 eV Nu_p = 3.262
* Incident neutron 1E+06 eV Nu_p = 3.369
* Incident neutron 4E+06 eV Nu_p = 3.769
* Incident neutron 1.4E+07 eV Nu_p = 5.057
* Incident neutron fission spectrum average Nu_p = 3.457
95-Am-243
* Atomic Mass: 243.0613727 +- 0.0000023 amu
* Excess Mass: 57168.280 +- 2.178 keV
* Binding Energy: 1829839.589 +- 2.203 keV
* Beta Decay Energy: B- -8.908 +- 1.434 keV
* Half Life: 7370 Y
Specific Activity: 0.1996 curie/g
Radioisotopic Power: 0.006433 W/g
Primary Mode of Decay: Alpha to Np-239
* Decay Energy: 5.438 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: 3.7E-9 %
* SF rate (fissions/sec/g) = 0.27
* Neutron emission rate (N/sec/g) = 0.76
* Spin: 5/2-
* Critical mass: 209 kg (C4/TMR2001/200-1), 38.1 kg (one-group calculation, assuming the same ratio between one-group and multi-group values as Am-241 a 'true' value of 140 kg can be estimated)
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)
* Incident neutron 1E-05 eV Nu_p = 3.265
* Incident neutron 2E+05 eV Nu_p = 3.292
* Incident neutron 1E+06 eV Nu_p = 3.403
* Incident neutron 4E+06 eV Nu_p = 3.812
* Incident neutron 1.4E+07 eV Nu_p = 5.129
* Incident neutron fission spectrum average Nu_p = 3.496
#### Californium
* Atomic number: 98
* Molar volume: 16.5 cm^3/mole
* Density: 15.1 (Cf-249, 25 C)
* Melting point: 900 C (+- 30 C)
* Boiling point:
98-Cf-249
* Atomic Mass: 249.0748468 +- 0.0000030 amu
* Excess Mass: 69719.351 +- 2.806 keV
* Binding Energy: 1863369.394 +- 2.826 keV
* Beta Decay Energy: B- -1451.000 +- 30.000 keV
* Half Life: 351 Y
Specific Activity: 4.089 curie/g
Radioisotopic Power: 0.1526 W/g
Primary Mode of Decay: Alpha to Cm-245
* Decay Energy: 6.295 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: 5.2E-7 %
* SF rate (fissions/sec/g) = 787
* Neutron emission rate (N/sec/g) = 2800
* Spin: 9/2-
* Critical mass: 5.91 kg (C4/TMR2001/200-1), 5.90 kg (one-group calculation)
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)
* Incident neutron 1E-05 eV Nu_p = 3.884
* Incident neutron 1E+05 eV Nu_p = 3.902
* Incident neutron 1E+06 eV Nu_p = 4.061
* Incident neutron 4E+06 eV Nu_p = 4.701
* Incident neutron 1.1E+07 eV Nu_p = 5.880
* Incident neutron fission spectrum average Nu_p = 4.221
98-Cf-251
* Atomic Mass: 251.0795801 +- 0.0000049 amu
* Excess Mass: 74128.333 +- 4.545 keV
* Binding Energy: 1875103.058 +- 4.558 keV
* Beta Decay Energy: B- -375.892 +- 7.107 keV
* Half Life: 898 Y
Specific Activity: 1.586 curie/g
Radioisotopic Power: 0.05805 W/g
Primary Mode of Decay: Alpha to Cm-247
* Decay Energy: 6.176 MeV
* Spin: 1/2+
* Critical mass: 5.46 kg (C4/TMR2001/200-1), 1.94 kg (one-group calculation)
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)
* Incident neutron 1E-05 eV Nu_p = 4.133
* Incident neutron 1E+05 eV Nu_p = 4.157
* Incident neutron 1E+06 eV Nu_p = 4.374
* Incident neutron 4E+06 eV Nu_p = 5.097
* Incident neutron 1.15E+07 eV Nu_p = 6.917
* Incident neutron fission spectrum average Nu_p = 4.560
98-Cf-252
* Atomic Mass: 252.0816196 +- 0.0000055 amu
* Excess Mass: 76028.139 +- 5.095 keV
* Binding Energy: 1881274.575 +- 5.106 keV
* Beta Decay Energy: B- -1260.000 +- 50.000 keV
* Half Life: 2.645 Y
Specific Activity: 536.2 curie/g
Radioisotopic Power: 38.8 W/g (about half fission, half alpha decay)
Primary Mode of Decay: Alpha to Cm-248
* Branch ratio: 96.91%
* Decay Energy: 6.217 MeV
Secondary Mode of Decay: Spontaneous fission
* Branch ratio: 3.09%
* Average neutron yield (Nu)
Nu_prompt = 3.7590 +- 0.0048
Nu_delayed = 0.0086 +- 0.0010
Nu_total = 3.7676 +- 0.004
* SF rate (fissions/sec/g) = 6.13E11
* Neutron emission rate (N/sec/g) = 2.31E12
* Spin: 0+
* Critical mass: 5.87-7.93 kg (C4/TMR2001/200-1), 2.73 kg (one-group calculation)
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)
- Incident neutron 1E-05 eV Nu_p = 4.060
- Incident neutron 1E+05 eV Nu_p = 4.087
- Incident neutron 1E+06 eV Nu_p = 4.325
- Incident neutron 4E+06 eV Nu_p = 5.119
- Incident neutron 1.5E+07 eV Nu_p = 7.961
- Incident neutron fission spectrum average Nu_p = 4.374