Английская Википедия:Fission product yield
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Шаблон:Short description Шаблон:Main
Nuclear fission splits a heavy nucleus such as uranium or plutonium into two lighter nuclei, which are called fission products. Yield refers to the fraction of a fission product produced per fission.
Yield can be broken down by:
- Individual isotope
- Chemical element spanning several isotopes of different mass number but same atomic number.
- Nuclei of a given mass number regardless of atomic number. Known as "chain yield" because it represents a decay chain of beta decay.
Isotope and element yields will change as the fission products undergo beta decay, while chain yields do not change after completion of neutron emission by a few neutron-rich initial fission products (delayed neutrons), with half-life measured in seconds.
A few isotopes can be produced directly by fission, but not by beta decay because the would-be precursor with atomic number one greater is stable and does not decay. Chain yields do not account for these "shadowed" isotopes; however, they have very low yields (less than a millionth as much as common fission products) because they are far less neutron-rich than the original heavy nuclei.
Yield is usually stated as percentage per fission, so that the total yield percentages sum to 200%. Less often, it is stated as percentage of all fission products, so that the percentages sum to 100%. Ternary fission, about 0.2–0.4% of fissions, also produces a third light nucleus such as helium-4 (90%) or tritium (7%).
Mass vs. yield curve
If a graph of the mass or mole yield of fission products against the atomic number of the fragments is drawn then it has two peaks, one in the area zirconium through to palladium and one at xenon through to neodymium. This is because the fission event causes the nucleus to split in an asymmetric manner,[1] as nuclei closer to magic numbers are more stable.[2]
Yield vs. Z - This is a typical distribution for the fission of uranium. Note that in the calculations used to make this graph the activation of fission products was ignored and the fission was assumed to occur in a single moment rather than a length of time. In this bar chart results are shown for different cooling times (time after fission).
Because of the stability of nuclei with even numbers of protons and/or neutrons the curve of yield against element is not a smooth curve. It tends to alternate.
In general, the higher the energy of the state that undergoes nuclear fission, the more likely a symmetric fission is, hence as the neutron energy increases and/or the energy of the fissile atom increases, the valley between the two peaks becomes more shallow; for instance, the curve of yield against mass for Pu-239 has a more shallow valley than that observed for U-235, when the neutrons are thermal neutrons. The curves for the fission of the later actinides tend to make even more shallow valleys. In extreme cases such as 259Fm, only one peak is seen.
Yield is usually expressed relative to number of fissioning nuclei, not the number of fission product nuclei, that is, yields should sum to 200%.
The table in the next section ("Ordered by yield") gives yields for notable radioactive (with half-lives greater than one year, plus iodine-131) fission products, and (the few most absorptive) neutron poison fission products, from thermal neutron fission of U-235 (typical of nuclear power reactors), computed from [1]Шаблон:Dead link.
The yields in the table sum to only 45.5522%, including 34.8401% which have half-lives greater than one year:
| t½ in years | Yield |
|---|---|
| 1 to 5 | 2.7252% |
| 10 to 100 | 12.5340% |
| 2 to 300,000 | 6.1251% |
| 1.5 to 16 million | 13.4494% |
The remainder and the unlisted 54.4478% decay with half-lives less than one year into nonradioactive nuclei.
This is before accounting for the effects of any subsequent neutron capture; e.g.:
- 135Xe capturing a neutron and becoming nearly stable 136Xe, rather than decaying to 135Cs which is radioactive with a half-life of 2.3 million years
- Nonradioactive 133Cs capturing a neutron and becoming 134Cs, which is radioactive with a half-life of 2 years
- Many of the fission products with mass 147 or greater such as 147Pm, 149Sm, 151Sm, and 155Eu have significant cross sections for neutron capture, so that one heavy fission product atom can undergo multiple successive neutron captures.
Besides fission products, the other types of radioactive products are
- plutonium containing 238Pu, 239Pu, 240Pu, 241Pu, and 242Pu,
- minor actinides including 237Np, 241Am, 243Am, curium isotopes, and perhaps californium
- reprocessed uranium containing 236U and other isotopes
- tritium
- activation products of neutron capture by the reactor or bomb structure or the environment
Fission products from U-235
| Yield | Element | Isotope | Halflife | Comment |
|---|---|---|---|---|
| 6.7896% | Caesium | Шаблон:Hs 133Cs → 134Cs | Шаблон:Ntsh 2.065 y | Neutron capture (29 barns) slowly converts stable 133Cs to 134Cs, which itself is low-yield because beta decay stops at 134Xe; can be further converted (140 barns) to 135Cs. |
| 6.3333% | Iodine, xenon | Шаблон:Hs 135I → 135Xe | Шаблон:Ntsh 6.57 h | Most important neutron poison; neutron capture converts 10–50% of 135Xe to 136Xe; remainder decays (9.14h) to 135Cs (2.3 My). |
| 6.2956% | Zirconium | Шаблон:Hs 93Zr | Шаблон:Ntsh 1.53 My | Long-lived fission product also produced by neutron activation in zircalloy cladding. |
| 6.1% | Molybdenum | Шаблон:Hs 99Mo | Шаблон:Ntsh 65.94 h | Its daughter nuclide 99mTc is important in medical diagnosing. |
| 6.0899% | Caesium | Шаблон:Hs 137Cs | Шаблон:Ntsh 30.17 y | Source of most of the decay heat from years to decades after irradiation, together with Шаблон:Chem. |
| 6.0507% | Technetium | Шаблон:Hs 99Tc | Шаблон:Ntsh 211 ky | Candidate for disposal by nuclear transmutation. |
| 5.7518% | Strontium | Шаблон:Hs 90Sr | Шаблон:Ntsh 28.9 y | Source of much of the decay heat together with Шаблон:Chem on the timespan of years to decades after irradiation. Formerly used in radioisotope thermoelectric generators. |
| 2.8336% | Iodine | Шаблон:Hs 131I | Шаблон:Ntsh 8.02 d | Reason for the use of potassium iodide tablets after nuclear accidents or nuclear bomb explosions. |
| 2.2713% | Promethium | Шаблон:Hs 147Pm | Шаблон:Ntsh 2.62 y | beta decays to very long lived Samarium-147 (half life>age of the universe); has seen some use in radioisotope thermoelectric generators |
| 1.0888% | Samarium | Шаблон:Hs 149Sm | Шаблон:Ntsh Observationally stable | 2nd most significant neutron poison. |
| 0.9%[3] | Iodine | Шаблон:Hs 129I | Шаблон:Ntsh 15.7 My | Long-lived fission product. Candidate for disposal by nuclear transmutation. |
| 0.4203% | Samarium | Шаблон:Hs 151Sm | Шаблон:Ntsh 90 y | Neutron poison; most will be converted to stable 152Sm. |
| 0.3912% | Ruthenium | Шаблон:Hs 106Ru | Шаблон:Ntsh 373.6 d | ruthenium tetroxide is volatile and chemically aggressive; daughter nuclide Шаблон:Chem decays quickly to stable Шаблон:Chem |
| 0.2717% | Krypton | Шаблон:Hs 85Kr | Шаблон:Ntsh 10.78 y | noble gas; has some uses in industry to detect fine cracks in materials via autoradiography |
| 0.1629% | Palladium | Шаблон:Hs 107Pd | Шаблон:Ntsh 6.5 My | Long-lived fission product; hampers extraction of stable isotopes of platinum group metals for use due to chemical similarity. |
| 0.0508% | Selenium | Шаблон:Hs 79Se | Шаблон:Ntsh 327 ky | |
| 0.0330% | Europium, gadolinium | Шаблон:Hs 155Eu → 155Gd | Шаблон:Ntsh 4.76 y | Both neutron poisons, most will be destroyed while fuel still in use. |
| 0.0297% | Antimony | Шаблон:Hs 125Sb | Шаблон:Ntsh 2.76 y | |
| 0.0236% | Tin | Шаблон:Hs 126Sn | Шаблон:Ntsh 230 ky | |
| 0.0065% | Gadolinium | Шаблон:Hs 157Gd | Шаблон:Ntsh stable | Neutron poison. |
| 0.0003% | Cadmium | Шаблон:Hs 113mCd | Шаблон:Ntsh 14.1 y | Neutron poison, most will be destroyed while fuel still in use. |
Cumulative fission yields
Cumulative fission yields give the amounts of nuclides produced either directly in the fission or by decay of other nuclides.
| Product | Thermal fission yield | Fast fission yield | 14-MeV fission yield |
|---|---|---|---|
| Шаблон:Nuclide | 0.00171 ± 0.00018 | 0.00269 ± 0.00044 | 0.00264 ± 0.00045 |
| Шаблон:Nuclide | 0.00084 ± 0.00015 | 0.00082 ± 0.00012 | 0.00081 ± 0.00012 |
| Шаблон:Nuclide | 0.0108 ± 0.0004 | 0.0108 ± 0.0004 | 0.0174 ± 0.0036 |
| Шаблон:Nuclide | 0.0108 ± 0.0004 | 0.0108 ± 0.0004 | 0.0174 ± 0.0036 |
| Шаблон:Nuclide | 0.1702 ± 0.0049 | 0.17 ± 0.0049 | 0.1667 ± 0.0088 |
| Шаблон:Nuclide | 1.304 ± 0.012 | 1.309 ± 0.043 | 1.64 ± 0.31 |
| Шаблон:Nuclide | 0.000285 ± 0.000076 | 0.00044 ± 0.00016 | 0.038 ± 0.012 |
| Шаблон:Nuclide | 0.286 ± 0.021 | 0.286 ± 0.026 | 0.47 ± 0.1 |
| Шаблон:Nuclide | 1.303 ± 0.012 | 1.307 ± 0.043 | 1.65 ± 0.31 |
| Шаблон:Nuclide | 5.73 ± 0.13 | 5.22 ± 0.18 | 4.41 ± 0.18 |
| Шаблон:Nuclide | 6.502 ± 0.072 | 6.349 ± 0.083 | 5.07 ± 0.19 |
| Шаблон:Nuclide | 0.00000042 ± 0.00000011 | 2.90±0.770 × 10−8 | 0.00004 ± 0.000015 |
| Шаблон:Nuclide | 6.498 ± 0.072 | 6.345 ± 0.083 | 5.07 ± 0.19 |
| Шаблон:Nuclide | 0.0702 ± 0.0067 | 0.0686 ± 0.0071 | 0.0548 ± 0.0072 |
| Шаблон:Nuclide | 0 ± 0 | 0 ± 0 | 0 ± 0 |
| Шаблон:Nuclide | 8.70 × 10−10 ± 3.20 × 10−10 | 0 ± 0 | 6.20 × 10−8 ± 2.50 × 10−8 |
| Шаблон:Nuclide | 0.00042 ± 0.00015 | 0.000069 ± 0.000025 | 0.0033 ± 0.0015 |
| Шаблон:Nuclide | 6.132 ± 0.092 | 5.8 ± 0.13 | 5.02 ± 0.13 |
| Шаблон:Nuclide | 6.132 ± 0.092 | 5.8 ± 0.13 | 5.02 ± 0.13 |
| Шаблон:Nuclide | 3.103 ± 0.084 | 3.248 ± 0.042 | 3.14 ± 0.11 |
| Шаблон:Nuclide | 0.41 ± 0.011 | 0.469 ± 0.036 | 2.15 ± 0.59 |
| Шаблон:Nuclide | 0.41 ± 0.011 | 0.469 ± 0.036 | 2.15 ± 0.59 |
| Шаблон:Nuclide | 0.00106 ± 0.00011 | 0.0039 ± 0.00091 | 0.142 ± 0.023 |
| Шаблон:Nuclide | 0.000000366 ± 0.000000098 | 0.0000004 ± 0.00000014 | 0.00193 ± 0.00068 |
| Шаблон:Nuclide | 0.000089 ± 0.000021 | 0.000112 ± 0.000034 | 0.027 ± 0.01 |
| Шаблон:Nuclide | 0.026 ± 0.0014 | 0.067 ± 0.011 | 1.42 ± 0.42 |
| Шаблон:Nuclide | 4.276 ± 0.043 | 4.639 ± 0.065 | 3.85 ± 0.16 |
| Шаблон:Nuclide | 0.706 ± 0.032 | 1.03 ± 0.26 | 1.59 ± 0.18 |
| Шаблон:Nuclide | 2.878 ± 0.032 | 3.365 ± 0.054 | 4.11 ± 0.14 |
| Шаблон:Nuclide | 6.59 ± 0.11 | 6.61 ± 0.13 | 5.42 ± 0.4 |
| Шаблон:Nuclide | 6.39 ± 0.22 | 6.01 ± 0.18 | 4.8 ± 1.4 |
| Шаблон:Nuclide | 0 ± 0 | 0 ± 0 | 0.00108 ± 0.00048 |
| Шаблон:Nuclide | 0.000038 ± 0.0000098 | 0.000152 ± 0.000055 | 0.038 ± 0.014 |
| Шаблон:Nuclide | 0.0313 ± 0.003 | 0.0365 ± 0.0031 | 0.047 ± 0.0049 |
| Шаблон:Nuclide | 6.6 ± 0.11 | 6.61 ± 0.13 | 5.57 ± 0.41 |
| Шаблон:Nuclide | 0.189 ± 0.015 | 0.19 ± 0.015 | 0.281 ± 0.049 |
| Шаблон:Nuclide | 6.61 ± 0.22 | 6.32 ± 0.18 | 6.4 ± 1.8 |
| Шаблон:Nuclide | 1.22 ± 0.12 | 1.23 ± 0.13 | 2.17 ± 0.66 |
| Шаблон:Nuclide | 0.0000121 ± 0.0000032 | 0.0000279 ± 0.0000073 | 0.0132 ± 0.0035 |
| Шаблон:Nuclide | 6.221 ± 0.069 | 5.889 ± 0.096 | 5.6 ± 1.3 |
| Шаблон:Nuclide | 6.314 ± 0.095 | 5.959 ± 0.048 | 4.474 ± 0.081 |
| Шаблон:Nuclide | 6.315 ± 0.095 | 5.96 ± 0.048 | 4.508 ± 0.081 |
| Шаблон:Nuclide | 5.86 ± 0.15 | 5.795 ± 0.081 | 4.44 ± 0.2 |
| Шаблон:Nuclide | 5.474 ± 0.055 | 5.094 ± 0.076 | 3.154 ± 0.038 |
| Шаблон:Nuclide | 5.474 ± 0.055 | 5.094 ± 0.076 | 3.155 ± 0.038 |
| Шаблон:Nuclide | 6.30 × 10−9 ± 1.70 × 10−9 | 1.70 × 10−9 ± 4.80 × 10−10 | 0.0000137 ± 0.0000049 |
| Шаблон:Nuclide | 5.475 ± 0.055 | 5.094 ± 0.076 | 3.155 ± 0.038 |
| Шаблон:Nuclide | 2.232 ± 0.04 | 2.148 ± 0.028 | 1.657 ± 0.045 |
| Шаблон:Nuclide | 2.232 ± 0.04 | 2.148 ± 0.028 | 1.657 ± 0.045 |
| Шаблон:Nuclide | 5.00 × 10−8 ± 1.70 × 10−8 | 7.40 × 10−9 ± 2.50 × 10−9 | 0.0000013 ± 0.00000042 |
| Шаблон:Nuclide | 0.000000104 ± 0.000000039 | 1.78 × 10−8 ± 6.60 × 10−9 | 0.0000048 ± 0.0000018 |
| Шаблон:Nuclide | 1.053 ± 0.021 | 1.064 ± 0.03 | 0.557 ± 0.09 |
| Шаблон:Nuclide | 0.4204 ± 0.0071 | 0.431 ± 0.015 | 0.388 ± 0.061 |
| Шаблон:Nuclide | 0.000000149 ± 0.000000041 | 2.43 × 10−8 ± 6.80 × 10−9 | 0.0000058 ± 0.0000018 |
| Шаблон:Nuclide | 0.000061 ± 0.000022 | 0.0000201 ± 0.0000077 | 0.00045 ± 0.00018 |
| Шаблон:Nuclide | 0.4204 ± 0.0071 | 0.431 ± 0.015 | 0.388 ± 0.061 |
| Шаблон:Nuclide | 0.1477 ± 0.0071 | 0.1512 ± 0.0097 | 0.23 ± 0.015 |
| Шаблон:Nuclide | 0.4204 ± 0.0071 | 0.431 ± 0.015 | 0.388 ± 0.061 |
| Шаблон:Nuclide | 3.24 × 10−10 ± 8.50 × 10−11 | 0 ± 0 | 3.30 × 10−8 ± 1.10 × 10−8 |
| Шаблон:Nuclide | 0.000000195 ± 0.000000064 | 4.00 × 10−8 ± 1.10 × 10−8 | 0.0000033 ± 0.0000011 |
| Шаблон:Nuclide | 0.0308 ± 0.0013 | 0.044 ± 0.01 | 0.088 ± 0.014 |
| Product | Thermal fission yield | Fast fission yield | 14-MeV fission yield |
|---|---|---|---|
| Шаблон:Nuclide | 0.00408 ± 0.00041 | 0.00346 ± 0.00057 | - |
| Шаблон:Nuclide | 0.00135 ± 0.00019 | 0.00106 ± 0.00016 | - |
| Шаблон:Nuclide | 0.0142 ± 0.0007 | 0.0142 ± 0.0007 | - |
| Шаблон:Nuclide | 0.0142 ± 0.0007 | 0.0142 ± 0.0007 | - |
| Шаблон:Nuclide | 0.2192 ± 0.009 | 0.219 ± 0.009 | - |
| Шаблон:Nuclide | 0.574 ± 0.026 | 0.617 ± 0.049 | - |
| Шаблон:Nuclide | 0.00175 ± 0.0006 | 0.00055 ± 0.0002 | - |
| Шаблон:Nuclide | 0.136 ± 0.014 | 0.138 ± 0.017 | - |
| Шаблон:Nuclide | 0.576 ± 0.026 | 0.617 ± 0.049 | - |
| Шаблон:Nuclide | 2.013 ± 0.054 | 2.031 ± 0.057 | - |
| Шаблон:Nuclide | 4.949 ± 0.099 | 4.682 ± 0.098 | - |
| Шаблон:Nuclide | 0.0000168 ± 0.0000045 | 0.00000255 ± 0.00000069 | - |
| Шаблон:Nuclide | 4.946 ± 0.099 | 4.68 ± 0.098 | - |
| Шаблон:Nuclide | 0.0535 ± 0.0066 | 0.0506 ± 0.0062 | - |
| Шаблон:Nuclide | 0 ± 0 | 0 ± 0 | - |
| Шаблон:Nuclide | 3.60 × 10−8 ± 1.30 × 10−8 | 4.80 × 10−9 ± 1.70 × 10−9 | - |
| Шаблон:Nuclide | 0.0051 ± 0.0018 | 0.0017 ± 0.00062 | - |
| Шаблон:Nuclide | 6.185 ± 0.056 | 5.82 ± 0.13 | - |
| Шаблон:Nuclide | 6.184 ± 0.056 | 5.82 ± 0.13 | - |
| Шаблон:Nuclide | 6.948 ± 0.083 | 6.59 ± 0.16 | - |
| Шаблон:Nuclide | 4.188 ± 0.092 | 4.13 ± 0.24 | - |
| Шаблон:Nuclide | 4.188 ± 0.092 | 4.13 ± 0.24 | - |
| Шаблон:Nuclide | 0.0052 ± 0.0011 | 0.0053 ± 0.0012 | - |
| Шаблон:Nuclide | 0.000024 ± 0.0000063 | 0.0000153 ± 0.000005 | - |
| Шаблон:Nuclide | 0.00228 ± 0.00049 | 0.00154 ± 0.00043 | - |
| Шаблон:Nuclide | 0.117 ± 0.015 | 0.138 ± 0.022 | - |
| Шаблон:Nuclide | 5.095 ± 0.094 | 4.92 ± 0.32 | - |
| Шаблон:Nuclide | 1.407 ± 0.086 | 1.31 ± 0.13 | - |
| Шаблон:Nuclide | 3.724 ± 0.078 | 4.09 ± 0.12 | - |
| Шаблон:Nuclide | 6.97 ± 0.13 | 6.99 ± 0.33 | - |
| Шаблон:Nuclide | 6.33 ± 0.23 | 6.24 ± 0.22 | - |
| Шаблон:Nuclide | 0.00000234 ± 0.00000085 | 0.0000025 ± 0.0000012 | - |
| Шаблон:Nuclide | 0.00166 ± 0.00056 | 0.00231 ± 0.00085 | - |
| Шаблон:Nuclide | 0.0405 ± 0.004 | 0.0444 ± 0.0044 | - |
| Шаблон:Nuclide | 6.99 ± 0.13 | 7.03 ± 0.33 | - |
| Шаблон:Nuclide | 0.216 ± 0.016 | 0.223 ± 0.021 | - |
| Шаблон:Nuclide | 7.36 ± 0.24 | 7.5 ± 0.23 | - |
| Шаблон:Nuclide | 1.78 ± 0.21 | 1.97 ± 0.25 | - |
| Шаблон:Nuclide | 0.00067 ± 0.00018 | 0.00115 ± 0.0003 | - |
| Шаблон:Nuclide | 6.588 ± 0.08 | 6.35 ± 0.12 | - |
| Шаблон:Nuclide | 5.322 ± 0.059 | 5.303 ± 0.074 | - |
| Шаблон:Nuclide | 5.333 ± 0.059 | 5.324 ± 0.075 | - |
| Шаблон:Nuclide | 5.205 ± 0.073 | 5.01 ± 0.16 | - |
| Шаблон:Nuclide | 3.755 ± 0.03 | 3.504 ± 0.053 | - |
| Шаблон:Nuclide | 3.756 ± 0.03 | 3.505 ± 0.053 | - |
| Шаблон:Nuclide | 0.00000145 ± 0.0000004 | 0.00000251 ± 0.00000072 | - |
| Шаблон:Nuclide | 3.756 ± 0.03 | 3.505 ± 0.053 | - |
| Шаблон:Nuclide | 2.044 ± 0.039 | 1.929 ± 0.046 | - |
| Шаблон:Nuclide | 2.044 ± 0.039 | 1.929 ± 0.046 | - |
| Шаблон:Nuclide | 0.0000056 ± 0.0000019 | 0.000012 ± 0.000004 | - |
| Шаблон:Nuclide | 0.0000118 ± 0.0000044 | 0.000029 ± 0.000011 | - |
| Шаблон:Nuclide | 1.263 ± 0.032 | 1.275 ± 0.056 | - |
| Шаблон:Nuclide | 0.776 ± 0.018 | 0.796 ± 0.037 | - |
| Шаблон:Nuclide | 0.0000168 ± 0.0000046 | 0.000039 ± 0.000011 | - |
| Шаблон:Nuclide | 0.00227 ± 0.00078 | 0.0051 ± 0.0019 | - |
| Шаблон:Nuclide | 0.776 ± 0.018 | 0.797 ± 0.037 | - |
| Шаблон:Nuclide | 0.38 ± 0.03 | 0.4 ± 0.18 | - |
| Шаблон:Nuclide | 0.776 ± 0.018 | 0.797 ± 0.037 | - |
| Шаблон:Nuclide | 0.000000195 ± 0.00000005 | 0.00000048 ± 0.00000014 | - |
| Шаблон:Nuclide | 0.000049 ± 0.000012 | 0.000127 ± 0.000043 | - |
| Шаблон:Nuclide | 0.174 ± 0.03 | 0.171 ± 0.054 | - |
| 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, Шаблон:ISBN. |
Ordered by mass number
Decays, even if lengthy, are given down to the stable nuclide.
Decays with half lives longer than a century are marked with a single asterisk (Шаблон:Asterisk), while decays with a half life longer than a hundred million years are marked with two asterisks (Шаблон:AsteriskШаблон:Asterisk).
Half lives, decay modes, and branching fractions
| Nuclide | Half-life | Decay mode | Branching fraction | Source | Notes |
|---|---|---|---|---|---|
| Шаблон:Nuclide | 2.9 ± 0.06 m | β− | 1.0 | [6] | Шаблон:Efn |
| Шаблон:Nuclide | 10.752 ± 0.023 y | β− | 1.0 | [7] | |
| Шаблон:Nuclide | 4.48 ± 0.008 h | IT | 0.214 ± 0.005 | [6] | |
| β− | 0.786 ± 0.005 | ||||
| Шаблон:Nuclide | 28.8 ± 0.07 y | β− | 1.0 | [8] | |
| Шаблон:Nuclide | 64.032 ± 0.006 d | β− | 1.0 | [8] | |
| Шаблон:Nuclide | (7.3 ± 0.9) × 106 d | β− | 1.0 | [9] | |
| Шаблон:Nuclide | 3.61 ± 0.03 d | β− | 0.025 ± 0.001 | [8] | Шаблон:Efn |
| IT | 0.975 ± 0.001 | ||||
| Шаблон:Nuclide | 34.985 ± 0.012 d | β− | 1.0 | [9] | |
| Шаблон:Nuclide | (2.111 ± 0.012) × 105 y | β− | 1.0 | [6] | |
| Шаблон:Nuclide | 39.247 ± 0.013 d | β− | 1.0 | [9] | |
| Шаблон:Nuclide | 1.018 ± 0.005 y | β− | 1.0 | [9] | |
| Шаблон:Nuclide | 30.1 ± 0.3 s | β− | 1.0 | [9] | |
| Шаблон:Nuclide | 55 ± 5 y | β− | 0.224 ± 0.02 | [6] | |
| IT | 0.776 ± 0.02 | ||||
| Шаблон:Nuclide | 2.7238 ± 0.0002 d | EC | 0.0241 ± 0.0012 | [6] | |
| β− | 0.9759 ± 0.0012 | ||||
| Шаблон:Nuclide | 60.2 ± 0.03 d | β− | 1.0 | [6] | |
| Шаблон:Nuclide | 2.7584 ± 0.0006 y | β− | 1.0 | [9] | |
| Шаблон:Nuclide | (5.89 ± 0.23) × 109 d | β− | 1.0 | [9] | |
| Шаблон:Nuclide | 8.0233 ± 0.0019 d | β− | 1.0 | [7] | |
| Шаблон:Nuclide | 20.87 ± 0.08 h | β− | 1.0 | [8] | Шаблон:Efn |
| Шаблон:Nuclide | 6.57 ± 0.02 h | β− | 1.0 | [6] | |
| Шаблон:Nuclide | 11.930 ± 0.016 d | IT | 1.0 | [7] | |
| Шаблон:Nuclide | 5.243 ± 0.001 d | β− | 1.0 | [6] | |
| Шаблон:Nuclide | 2.19 ± 0.01 d | IT | 1.0 | [6] | |
| Шаблон:Nuclide | 9.14 ± 0.02 h | β− | 1.0 | [6] | |
| Шаблон:Nuclide | 15.29 ± 0.05 m | β− | 0.003 ± 0.003 | [6] | Шаблон:Efn |
| IT | 0.997 ± 0.003 | ||||
| Шаблон:Nuclide | 2.063 ± 0.003 y | EC | 0.000003 ± 0.000001 | [9] | Шаблон:Efn |
| β− | 0.999997 ± 0.000001 | ||||
| Шаблон:Nuclide | 30.05 ± 0.08 y | β− | 1.0 | [9] | |
| Шаблон:Nuclide | 12.753 ± 0.004 d | β− | 1.0 | [7] | |
| Шаблон:Nuclide | 1.67850 ± 0.00017 d | β− | 1.0 | [7] | |
| Шаблон:Nuclide | 32.508 ± 0.010 d | β− | 1.0 | [8] | |
| Шаблон:Nuclide | 285.1 ± 0.6 d | β− | 1.0 | [9] | |
| Шаблон:Nuclide | 17.28 ± 0.05 m | β− | 1.0 | [6] | |
| Шаблон:Nuclide | 10.98 ± 0.01 d | β− | 1.0 | [6] | |
| Шаблон:Nuclide | 2.6234 ± 0.0002 y | β− | 1.0 | [6] | |
| Шаблон:Nuclide | 41.29 ± 0.11 d | IT | 0.042 ± 0.007 | [6] | |
| β− | 0.958 ± 0.007 | ||||
| Шаблон:Nuclide | 5.368 ± 0.002 d | β− | 1.0 | [6] | |
| Шаблон:Nuclide | 2.2117 ± 0.0021 d | β− | 1.0 | [6] | |
| Шаблон:Nuclide | 1.1833 ± 0.0017 d | β− | 1.0 | [6] | |
| Шаблон:Nuclide | 90 ± 6 y | β− | 1.0 | [6] | |
| Шаблон:Nuclide | 1.938 ± 0.010 d | β− | 1.0 | [9] | |
| Шаблон:Nuclide | (4.941 ± 0.007) × 103 d | β− | 0.279 ± 0.003 | [9] | Шаблон:Efn |
| EC | 0.721 ± 0.003 | ||||
| Шаблон:Nuclide | (3.1381 ± 0.0014) × 103 d | EC | 0.00018 ± 0.00013 | [9] | Шаблон:Efn |
| β− | 0.99982 ± 0.00013 | ||||
| Шаблон:Nuclide | 4.753 ± 0.016 y | β− | 1.0 | [9] |
Ordered by thermal neutron absorption cross section
| Barns | Yield | Isotope | t½ | Comment |
|---|---|---|---|---|
| Шаблон:Nts | 6.3333% | Шаблон:Hs 135I → 135Xe | Шаблон:Ntsh 6.57 h | Most important neutron poison; neutron capture rapidly converts 135Xe to 136Xe; remainder decays (9.14 h) to 135Cs (2.3 My). |
| Шаблон:Nts | 0.0065% | Шаблон:Hs 157Gd | ∞ | Neutron poison, but low yield. |
| Шаблон:Nts | 1.0888% | Шаблон:Hs 149Sm | ∞ | 2nd most important neutron poison. |
| Шаблон:Nts | 0.0003% | Шаблон:Hs 113mCd | Шаблон:Ntsh 14.1 y | Most will be destroyed by neutron capture. |
| Шаблон:Nts | 0.4203% | Шаблон:Hs 151Sm | Шаблон:Ntsh 90 y | Most will be destroyed by neutron capture. |
| Шаблон:Nts 60,900 |
0.0330% | Шаблон:Hs 155Eu → 155Gd | Шаблон:Ntsh 4.76 y | Both neutron poisons. |
| Шаблон:Nts | 2.2713% | Шаблон:Hs 147Pm | Шаблон:Ntsh 2.62 y | Suitable for radioisotope thermoelectric generators with annual or semi-annual refueling. |
| Шаблон:Nts | 2.8336% | Шаблон:Hs 131I | Шаблон:Ntsh 8.02 d | |
| Шаблон:Nts 140 |
6.7896% | Шаблон:Hs 133Cs → 134Cs | ∞ 2.065 y |
Neutron capture converts a few percent of nonradioactive 133Cs to 134Cs, which has very low direct yield because beta decay stops at 134Xe; further capture will add to long-lived 135Cs. |
| Шаблон:Nts | 6.0507% | Шаблон:Hs 99Tc | Шаблон:Ntsh 211 ky | Candidate for disposal by nuclear transmutation. |
| Шаблон:Nts | 0.6576% | Шаблон:Hs 129I | Шаблон:Ntsh 15.7 My | Candidate for disposal by nuclear transmutation. |
| Шаблон:Nts | 6.2956% | Шаблон:Hs 93Zr | Шаблон:Ntsh 1.53 My | Transmutation impractical. |
| Шаблон:Nts | 0.1629% | Шаблон:Hs 107Pd | Шаблон:Ntsh 6.5 My | |
| Шаблон:Nts | 0.2717% | Шаблон:Hs 85Kr | Шаблон:Ntsh 10.78 y | |
| Шаблон:Nts | 5.7518% | Шаблон:Hs 90Sr | Шаблон:Ntsh 28.9 y | |
| Шаблон:Nts | 0.3912% | Шаблон:Hs 106Ru | Шаблон:Ntsh 373.6 d | |
| Шаблон:Nts | 6.0899% | Шаблон:Hs 137Cs | Шаблон:Ntsh 30.17 y | |
| 0.0297% | Шаблон:Hs 125Sb | Шаблон:Ntsh 2.76 y | ||
| 0.0236% | Шаблон:Hs 126Sn | Шаблон:Ntsh 230 ky | ||
| 0.0508% | Шаблон:Hs 79Se | Шаблон:Ntsh 327 ky |
References
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite journal
- ↑ Purkayastha, B. C., and G. R. Martin. "The yields of 129I in natural and in neutron-induced fission of uranium." Canadian Journal of Chemistry 34.3 (1956): 293-300.
- ↑ 4,0 4,1 Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ 6,00 6,01 6,02 6,03 6,04 6,05 6,06 6,07 6,08 6,09 6,10 6,11 6,12 6,13 6,14 6,15 6,16 6,17 6,18 Evaluated Nuclear Structure Data File, http://www-nds.iaea.org/ensdf/, 26 January 2006.
- ↑ 7,0 7,1 7,2 7,3 7,4 M.-M. Bé, V. Chisté, C. Dulieu, E. Browne, V. Chechev, N. Kuzmenko, R. Helmer, A. Nichols, E. Schönfeld, R. Dersch, Monographie BIPM-5, Table of Radionuclides, Vol. 2 - A = 151 to 242, 2004.
- ↑ 8,0 8,1 8,2 8,3 8,4 Laboratoire National Henri Becquerel, Recommended Data, http://www.nucleide.org/DDEP_WG/DDEPdata.htm, 16 January 2006.
- ↑ 9,00 9,01 9,02 9,03 9,04 9,05 9,06 9,07 9,08 9,09 9,10 9,11 9,12 9,13 M.-M. Bé, V.P. Chechev, R. Dersch, O.A.M. Helene, R.G. Helmer, M. Herman, S. Hlavác, A. Marcinkowski, G.L. Molnár, A.L. Nichols, E. Schönfeld, V.R. Vanin, M.J. Woods, IAEA CRP "Update of X-ray and Gamma-ray Decay Data Standards for Detector Calibration and Other Applications", IAEA Scientific and Technical Information report STI/PUB/1287, May 2007, International Atomic Energy Agency, Vienna, Austria, Шаблон:ISBN.
External links
- HANDBOOK OF NUCLEAR DATA FOR SAFEGUARDS: DATABASE EXTENSIONS, AUGUST 2008
- Файл:Ndslivechart.png The Live Chart of Nuclides - IAEA Color-map of yields, and detailed data by click on a nuclide.
