644:
1839:"The isotopic analyses disclosed a species of mass 248 in constant abundance in three samples analysed over a period of about 10 months. This was ascribed to an isomer of Bk with a half-life greater than 9 . No growth of Cf was detected, and a lower limit for the β half-life can be set at about 10 . No alpha activity attributable to the new isomer has been detected; the alpha half-life is probably greater than 300 ."
1754:, and it has not been disclosed which definition was used in describing the material this way. The plutonium was apparently sourced from the military Magnox reactors at Calder Hall or Chapelcross. The content of Pu-239 in material used for the 1962 test was not disclosed, but has been inferred to have been at least 85%, much higher than typical spent fuel from currently operating reactors.
1757:
Occasionally, low-burnup spent fuel has been produced by a commercial LWR when an incident such as a fuel cladding failure has required early refuelling. If the period of irradiation has been sufficiently short, this spent fuel could be reprocessed to produce weapons grade plutonium.
1015:
The critical mass for any isotope is influenced by any impurities and the physical shape of the material. The shape with minimal critical mass and the smallest physical dimensions is a sphere. Bare-sphere critical masses at normal density of some
999:
have different critical masses, and the critical mass for many radioactive isotopes is infinite, because the mode of decay of one atom cannot induce similar decay of more than one neighboring atom. For example, the critical mass of
1696:, typically about 93% Pu-239. Pu-240 is produced when Pu-239 absorbs an additional neutron and fails to fission. Pu-240 and Pu-239 are not separated by reprocessing. Pu-240 has a high rate of
1746:(then known as the Nevada Proving Grounds) used non-weapons-grade plutonium produced in a Magnox reactor in the United Kingdom. The plutonium used was provided to the United States under the
1738:
Plutonium recovered from LWR spent fuel, while not weapons grade, can be used to produce nuclear weapons at all levels of sophistication, though in simple designs it may produce only a
43:
1980:
995:
that is small enough to justify its use in a weapon. The critical mass for any material is the smallest amount needed for a sustained nuclear chain reaction. Moreover, different
2075:. Proceedings of the Seventh International Conference on Nuclear Criticality Safety. Vol. II. Tokai, Ibaraki, Japan: Japan Atomic Energy Research Institute. pp. 618–623.
2472:
1719:
This represents a fundamental difference between these two types of reactor. In a nuclear power station, high burnup is desirable. Power stations such as the obsolete
British
776:
1890:
2167:
1513:
1735:
most commonly used to produce electric power. In these the reactor must be shut down and the pressure vessel disassembled to gain access to the irradiated fuel.
1493:
782:
1622:. The U-233 produced thus does not require enrichment and can be relatively easily chemically separated from residual Th-232. It is therefore regulated as a
1572:
843:
1556:
832:
36:
853:
1501:
884:
2418:
1773:
Plus radium (element 88). While actually a sub-actinide, it immediately precedes actinium (89) and follows a three-element gap of instability after
1727:
reactors, which were designed to produce either electricity or weapons material, were operated at low power levels with frequent fuel changes using
1548:
827:
613:
1747:
1742:
yield. Weapons made with reactor-grade plutonium would require special cooling to keep them in storage and ready for use. A 1962 test at the U.S.
1949:
2220:
Nonproliferation and Arms
Control Assessment of Weapons-Usable Fissile Material Storage and Excess Plutonium Disposition Alternatives (excerpted)
1569:, which is widely known to have developed nuclear weapons (likely first tested in the 1960s or 1970s) but has not openly declared its capability
1521:
1505:
797:
787:
29:
2002:
2450:
1540:
1529:
813:
802:
792:
2355:
1525:
717:
848:
766:
1812:
Milsted, J.; Friedman, A. M.; Stevens, C. M. (1965). "The alpha half-life of berkelium-247; a new long-lived isomer of berkelium-248".
1020:
are listed in the accompanying table. Most information on bare sphere masses is classified, but some documents have been declassified.
1865:" nuclides with half-lives significantly in excess of Th; e.g., while Cd has a half-life of only fourteen years, that of Cd is eight
1629:
While U-233 would thus seem ideal for weaponization, a significant obstacle to that goal is the co-production of trace amounts of
1489:
2065:
1952:, Republic of France, Institut de Radioprotection et de Sûreté Nucléaire, Département de Prévention et d'étude des Accidents.
1560:
2381:
1866:
1743:
877:
695:
2297:
247:
208:
175:
148:
1704:. To reduce the concentration of Pu-240 in the plutonium produced, weapons program plutonium production reactors (e.g.
1626:
only by the total amount present. U-233 may be intentionally down-blended with U-238 to remove proliferation concerns.
858:
2495:
2097:"Critical and Subcritical Mass Calculations of Curium-243 to -247 Based on JENDL-3.2 for Revision of ANSI/ANS-8.15"
1566:
818:
663:
539:
508:
485:
463:
432:
1883:
969:
might be usable, but it is not clear that this has ever been implemented. The latter substances are part of the
2490:
2330:
1642:
1623:
917:
870:
683:
1966:
2458:
2359:
2161:"Uranium Enrichment: Just Plain Facts to Fuel an Informed Debate on Nuclear Proliferation and Nuclear Power"
1701:
1672:
1658:
1608:
712:
678:
2471:
can readily be used to make high-performance, high-reliability nuclear weaponry, as explained in the 1994
1962:
1497:
2415:
2246:
1739:
1709:
1485:
752:
737:
673:
84:
2133:
1777:(84) where no nuclides have half-lives of at least four years (the longest-lived nuclide in the gap is
916:
in grades normally used in nuclear weapons are the most common examples. (These nuclear materials have
2462:
1821:
1686:
700:
688:
2042:
1732:
1697:
1592:
1517:
742:
2500:
1950:
Final Report, Evaluation of nuclear criticality safety data and limits for actinides in transport
1862:
1849:
1533:
974:
958:
943:
1633:
due to side-reactions. U-232 hazards, a result of its highly radioactive decay products such as
1700:, which can cause a nuclear weapon to pre-detonate. This makes plutonium unsuitable for use in
2446:
2438:
2356:"Additional Information Concerning Underground Nuclear Weapon Test of Reactor-Grade Plutonium"
2266:
1728:
1682:
1638:
747:
732:
727:
722:
658:
1928:
2505:
2430:
2274:
2258:
2108:
1994:
1829:
1785:). Radium's longest lived isotope, at 1,600 years, thus merits the element's inclusion here.
901:
99:
2146:
942:
in the element used must be sufficiently high. Uranium from natural sources is enriched by
2426:
2422:
2247:"MANAGING MILITARY URANIUM AND PLUTONIUM IN THE UNITED STATES AND THE FORMER SOVIET UNION"
2187:
1799:
1795:
1678:
1619:
1588:
970:
947:
668:
600:
117:
76:
1661:
would require low U-232 levels and low levels of light impurities on the order of 1 PPM.
1825:
1685:
in a rapid two-step process into Pu-239. It can then be separated from the uranium in a
2293:
2026:
1879:
1712:. More precisely, weapons-grade plutonium is obtained from uranium irradiated to a low
1544:
1229:
905:
757:
705:
635:
620:
108:
91:
2134:"Evaluation of nuclear criticality safety. data and limits for actinides in transport"
2484:
2160:
1833:
1576:
1247:
1211:
1193:
1175:
1157:
1139:
1121:
1103:
1085:
992:
986:
962:
939:
931:
2262:
1645:
require U-232 levels below 50 PPM (above which the U-233 is considered "low grade";
2242:
2202:
1985:
1634:
2113:
2096:
1848:
This is the heaviest nuclide with a half-life of at least four years before the "
1575:, which also had enrichment capabilities and developed nuclear weapons (possibly
1630:
1615:
1600:
1455:
1436:
1417:
1398:
1067:
1049:
1009:
1005:
1001:
954:
935:
934:
for use in nuclear weapons. For such use, the concentration of fissile isotopes
80:
60:
2385:
908:
and has properties that make it particularly suitable for nuclear weapons use.
2468:
1750:. Its isotopic composition has not been disclosed, other than the description
2304:
2270:
2029:, U.S. Department of Energy: Office of Scientific & Technical Information
1910:
1778:
1731:
to produce weapons-grade plutonium. Such operation is not possible with the
1705:
1379:
1360:
966:
909:
65:
1911:
Reevaluated
Critical Specifications of Some Los Alamos Fast-Neutron Systems
1884:"Neptunium 237 and Americium: World Inventories and Proliferation Concerns"
2278:
1611:
is considered weapons-grade when it has been enriched to about 90% U-235.
2147:
Nuclear
Weapons Frequently Asked Questions: Section 6.0 Nuclear Materials
1774:
1552:
1539:
Three other declared nuclear states that are not signatories of the NPT:
1017:
56:
1596:
996:
927:
924:
913:
643:
607:
1653:
content of no more than 6.5%." which is 65,000 PPM, and the analogous
1720:
1713:
1693:
1654:
1650:
1480:
At least ten countries have produced weapons-grade nuclear material:
1341:
1322:
1303:
1284:
1265:
1998:
1708:) irradiate the uranium for a far shorter time than is normal for a
2159:
Makhijani, Arjun; Chalmers, Lois; Smith, Brice (October 15, 2004).
1509:
2409:
2216:"Reactor-Grade and Weapons-Grade Plutonium in Nuclear Explosives"
2215:
2190:
1724:
1604:
70:
2410:
Reactor-Grade and
Weapons-Grade Plutonium in Nuclear Explosives
1681:
when a neutron is absorbed by U-238, forming U-239, which then
2465:
2073:
Challenges in the
Pursuit of Global Nuclear Criticality Safety
1646:
623:(thermal neutron capture cross section greater than 3k barns)
1476:
Countries that have produced weapons-grade nuclear material
16:
Nuclear material pure enough to be used for nuclear weapons
1692:
Weapons-grade plutonium is defined as being predominantly
1579:), but disassembled its arsenal and joined the NPT in 1991
1963:
Troubles tomorrow? Separated
Neptunium 237 and Americium
2439:"The Nuclear Fuel Cycle: Does Reprocessing Make Sense?"
2384:. World Nuclear Association. March 2009. Archived from
2064:
Dias, Hemanth; Tancock, Nigel; Clayton, Angela (2003).
1932:
1981:"Neptunium Nukes? Little-studied metal goes critical"
2473:
2331:"U.S. Policy on Spent Fuel Reprocessing: The Issues"
2132:
2049:, Vol. 283, No. 5750, pp. 817–823, February 28, 1980
1657:
was produced in levels of 0.5% (5000 PPM) or less).
2027:Updated Critical Mass Estimates for Plutonium-238
2298:"Reactor Grade Plutonium's Explosive Properties"
1891:Institute for Science and International Security
2412:, Canadian Coalition for Nuclear Responsibility
2168:Institute for Energy and Environmental Research
1603:(U-238). They are separated by their differing
991:Any weapons-grade nuclear material must have a
585:
580:
573:
552:
545:
533:
524:
404:
399:
385:
2066:"Critical Mass Calculations for Am, Am and Am"
469:
455:
448:
441:
436:
424:
419:
414:
878:
517:
512:
498:
489:
367:
362:
350:
345:
340:
335:
325:
320:
306:
299:
275:
270:
261:
256:
251:
241:
236:
229:
222:
217:
212:
202:
197:
192:
187:
37:
8:
2095:Okuno, Hiroshi; Kawasaki, Hiromitsu (2002).
1649:"Standard weapon grade plutonium requires a
25:Actinides and fission products by half-life
2416:Nuclear weapons and power-reactor plutonium
2303:. Nuclear Control Institute. Archived from
2251:Annual Review of Energy and the Environment
2043:Nuclear weapons and power-reactor plutonium
1599:U-235, with the rest being almost entirely
292:in the range of 100 a–210 ka ...
163:
154:
136:
1798:fission of uranium-235, e.g. in a typical
1022:
1004:is infinite, while the critical masses of
957:(the fissile material at the heart of the
946:, and plutonium is produced in a suitable
885:
871:
642:
631:
44:
30:
2222:. U.S. Department of Energy. January 1997
2112:
2101:Journal of Nuclear Science and Technology
2188:Definition of Weapons-Usable Uranium-233
1945:
1943:
1941:
614:naturally occurring radioactive material
603:cross section in the range of 8–50 barns
2128:
2126:
2124:
2090:
2088:
2086:
2084:
2082:
2059:
2057:
2055:
1882:and Kimberly Kramer (August 22, 2005).
1766:
765:
650:
634:
2433:, Vol. 283, No. 5750, pp. 817–823
2037:
2035:
2022:
2020:
1967:Challenges of Fissile Material Control
1929:Nuclear Weapons Design & Materials
1933:The Nuclear Threat Initiative website
1924:
1922:
1920:
1918:
1595:. Initially only about 0.7% of it is
953:Experiments have been conducted with
566:
285:
7:
1781:with a half life of less than four
1748:1958 US–UK Mutual Defence Agreement
1677:Pu-239 is produced artificially in
14:
2445:. World Scientific. p. 144.
431:
1559:(withdrew from the NPT in 2003,
1490:Nuclear Non-Proliferation Treaty
2457:But there is no doubt that the
2263:10.1146/ANNUREV.ENERGY.22.1.403
1591:is made weapons-grade through
904:that is pure enough to make a
898:Weapons-grade nuclear material
1:
2441:. In B. van der Zwaan (ed.).
2114:10.1080/18811248.2002.9715296
1979:P. Weiss (October 26, 2002).
1744:Nevada National Security Site
930:of certain elements have the
1834:10.1016/0029-5582(65)90719-4
1637:, are significant even at 5
568:... nor beyond 15.7 Ma
2437:Garwin, Richard L. (1999).
1510:first weapon tested in 1949
1498:first nuclear weapon tested
287:No fission products have a
20:
2522:
1670:
984:
1643:Implosion nuclear weapons
1488:" under the terms of the
595:
75:
64:
55:
23:
1702:gun-type nuclear weapons
1659:Gun-type fission weapons
1624:special nuclear material
920:based on their purity.)
2459:reactor-grade plutonium
2421:March 16, 2007, at the
2360:US Department of Energy
1969:(1999), isis-online.org
1673:Reactor-grade plutonium
1665:Weapons-grade plutonium
1614:U-233 is produced from
1609:Highly enriched uranium
1502:used as weapons in 1945
2429:, February 28, 1980,
1710:nuclear power reactor
1584:Weapons-grade uranium
1561:weapon tested in 2006
1553:weapon tested in 1998
1545:weapon tested in 1974
1486:nuclear-weapon states
965:and some isotopes of
918:other categorizations
612:№, primarily a
599:₡, has thermal
2475:(CISAC) publication.
2005:on December 15, 2012
1733:light water reactors
1687:nuclear reprocessing
767:Nuclear-armed states
1826:1965NucPh..71..299M
1698:spontaneous fission
1593:isotopic enrichment
900:is any fissionable
2241:Matthew Bunn and;
1863:classically stable
1850:sea of instability
1794:Specifically from
1551:(not a signatory,
1543:(not a signatory,
975:spent nuclear fuel
959:thorium fuel cycle
944:isotope separation
176:> 9 a
2496:Nuclear materials
2452:978-981-02-4011-0
2388:on March 30, 2010
2245:(November 1997).
2203:Nuclear Materials
2149:February 20, 1999
2107:(10): 1072–1085.
2041:Amory B. Lovins,
1861:Excluding those "
1729:online refuelling
1639:parts per million
1484:Five recognized "
1473:
1472:
895:
894:
659:Nuclear explosion
630:
629:
591:0.7–14.1 Ga
587:
582:
575:
554:
547:
535:
526:
519:
514:
500:
491:
471:
457:
450:
443:
438:
426:
421:
416:
406:
401:
387:
369:
364:
352:
347:
342:
337:
327:
322:
308:
301:
277:
272:
263:
258:
253:
243:
238:
231:
224:
219:
214:
204:
199:
194:
189:
165:
156:
138:
2513:
2477:
2398:
2397:
2395:
2393:
2378:
2372:
2371:
2369:
2367:
2352:
2346:
2345:
2343:
2341:
2326:
2320:
2319:
2317:
2315:
2309:
2302:
2290:
2284:
2282:
2238:
2232:
2231:
2229:
2227:
2212:
2206:
2200:
2194:
2185:
2179:
2178:
2176:
2174:
2165:
2156:
2150:
2145:Carey Sublette,
2143:
2137:
2130:
2119:
2118:
2116:
2092:
2077:
2076:
2070:
2061:
2050:
2039:
2030:
2024:
2015:
2014:
2012:
2010:
2001:. Archived from
1976:
1970:
1959:
1953:
1947:
1936:
1926:
1913:
1908:
1902:
1901:
1899:
1897:
1888:
1876:
1870:
1859:
1853:
1846:
1840:
1837:
1809:
1803:
1792:
1786:
1771:
1679:nuclear reactors
1023:
902:nuclear material
887:
880:
873:
824:
718:Target selection
646:
632:
586:
581:
574:
553:
546:
534:
525:
518:
513:
509:1.61–6.5 Ma
499:
490:
470:
456:
449:
442:
437:
425:
420:
415:
405:
400:
386:
375:8.3–8.5 ka
368:
363:
356:4.7–7.4 ka
351:
346:
341:
336:
331:1.3–1.6 ka
326:
321:
307:
300:
290:
276:
271:
262:
257:
252:
242:
237:
230:
223:
218:
213:
203:
198:
193:
188:
164:
155:
137:
77:Fission products
46:
39:
32:
21:
2521:
2520:
2516:
2515:
2514:
2512:
2511:
2510:
2491:Nuclear weapons
2481:
2480:
2453:
2436:
2427:Amory B. Lovins
2423:Wayback Machine
2406:
2401:
2391:
2389:
2380:
2379:
2375:
2365:
2363:
2354:
2353:
2349:
2339:
2337:
2329:Rossin, David.
2328:
2327:
2323:
2313:
2311:
2307:
2300:
2296:(August 1990).
2292:
2291:
2287:
2243:John P. Holdren
2240:
2239:
2235:
2225:
2223:
2214:
2213:
2209:
2201:
2197:
2186:
2182:
2172:
2170:
2163:
2158:
2157:
2153:
2144:
2140:
2131:
2122:
2094:
2093:
2080:
2068:
2063:
2062:
2053:
2040:
2033:
2025:
2018:
2008:
2006:
1999:10.2307/4014034
1978:
1977:
1973:
1960:
1956:
1948:
1939:
1927:
1916:
1909:
1905:
1895:
1893:
1886:
1878:
1877:
1873:
1860:
1856:
1847:
1843:
1838:
1814:Nuclear Physics
1811:
1810:
1806:
1800:nuclear reactor
1796:thermal neutron
1793:
1789:
1772:
1768:
1764:
1675:
1667:
1620:neutron capture
1589:Natural uranium
1586:
1478:
1040:
1035:
1030:
989:
983:
971:minor actinides
948:nuclear reactor
891:
842:
822:
812:
781:
636:Nuclear weapons
626:
601:neutron capture
464:327–375 ka
433:150–250 ka
312:430–900 a
291:
288:
283:141–351 a
68:
51:
50:
17:
12:
11:
5:
2519:
2517:
2509:
2508:
2503:
2498:
2493:
2483:
2482:
2479:
2478:
2461:obtained from
2451:
2443:Nuclear energy
2434:
2413:
2405:
2404:External links
2402:
2400:
2399:
2373:
2347:
2321:
2310:on May 8, 2010
2294:J. Carson Mark
2285:
2257:(1): 403–486.
2233:
2207:
2195:
2180:
2151:
2138:
2120:
2078:
2051:
2031:
2016:
1971:
1954:
1937:
1914:
1903:
1880:David Albright
1871:
1854:
1841:
1804:
1787:
1765:
1763:
1760:
1666:
1663:
1585:
1582:
1581:
1580:
1577:tested in 1979
1570:
1564:
1537:
1514:United Kingdom
1500:and two bombs
1477:
1474:
1471:
1470:
1468:
1465:
1462:
1459:
1452:
1451:
1449:
1446:
1443:
1440:
1433:
1432:
1430:
1427:
1424:
1421:
1414:
1413:
1411:
1408:
1405:
1402:
1395:
1394:
1392:
1389:
1386:
1383:
1376:
1375:
1373:
1370:
1367:
1364:
1357:
1356:
1354:
1351:
1348:
1345:
1338:
1337:
1335:
1332:
1329:
1326:
1319:
1318:
1316:
1313:
1310:
1307:
1300:
1299:
1297:
1294:
1291:
1288:
1281:
1280:
1278:
1275:
1272:
1269:
1262:
1261:
1259:
1256:
1253:
1250:
1244:
1243:
1241:
1238:
1235:
1232:
1230:americium-242m
1226:
1225:
1223:
1220:
1217:
1214:
1208:
1207:
1205:
1202:
1199:
1196:
1190:
1189:
1187:
1184:
1181:
1178:
1172:
1171:
1169:
1166:
1163:
1160:
1154:
1153:
1151:
1148:
1145:
1142:
1136:
1135:
1133:
1130:
1127:
1124:
1118:
1117:
1115:
1112:
1109:
1106:
1100:
1099:
1097:
1094:
1091:
1088:
1082:
1081:
1079:
1076:
1073:
1070:
1064:
1063:
1061:
1058:
1055:
1052:
1046:
1045:
1042:
1037:
1032:
1027:
1012:are finite.
985:Main article:
982:
979:
906:nuclear weapon
893:
892:
890:
889:
882:
875:
867:
864:
863:
862:
861:
856:
851:
846:
836:
835:
830:
825:
816:
806:
805:
800:
795:
793:United Kingdom
790:
785:
770:
769:
763:
762:
761:
760:
755:
750:
745:
740:
735:
730:
725:
720:
715:
709:
708:
703:
698:
692:
691:
686:
681:
676:
671:
666:
661:
653:
652:
648:
647:
639:
638:
628:
627:
625:
624:
621:neutron poison
617:
610:
604:
596:
593:
592:
589:
584:
579:
577:
571:
570:
565:
562:
560:
558:
556:
550:
549:
544:
542:
537:
532:
530:
528:
522:
521:
516:
511:
506:
504:
502:
497:
494:
493:
488:
483:
481:
479:
477:
474:
473:
468:
466:
461:
459:
454:
452:
446:
445:
440:
435:
430:
428:
423:
418:
412:
411:
410:32–76 ka
408:
403:
398:
396:
393:
392:
389:
384:
382:
380:
377:
376:
373:
371:
366:
361:
358:
357:
354:
349:
344:
339:
333:
332:
329:
324:
319:
317:
314:
313:
310:
305:
303:
298:
295:
294:
284:
281:
279:
274:
269:
266:
265:
260:
255:
250:
245:
240:
235:
233:
227:
226:
221:
216:
211:
206:
201:
196:
191:
185:
184:
182:
180:
178:
173:
171:
169:
167:
161:
160:
158:
153:
151:
146:
144:
142:
140:
134:
133:
130:
127:
124:
115:
106:
97:
88:
87:
74:
63:
53:
52:
49:
48:
41:
34:
26:
24:
15:
13:
10:
9:
6:
4:
3:
2:
2518:
2507:
2504:
2502:
2499:
2497:
2494:
2492:
2489:
2488:
2486:
2476:
2474:
2470:
2467:
2464:
2460:
2454:
2448:
2444:
2440:
2435:
2432:
2428:
2424:
2420:
2417:
2414:
2411:
2408:
2407:
2403:
2387:
2383:
2377:
2374:
2361:
2357:
2351:
2348:
2336:
2332:
2325:
2322:
2306:
2299:
2295:
2289:
2286:
2280:
2276:
2272:
2268:
2264:
2260:
2256:
2252:
2248:
2244:
2237:
2234:
2221:
2217:
2211:
2208:
2204:
2199:
2196:
2192:
2189:
2184:
2181:
2169:
2162:
2155:
2152:
2148:
2142:
2139:
2135:
2129:
2127:
2125:
2121:
2115:
2110:
2106:
2102:
2098:
2091:
2089:
2087:
2085:
2083:
2079:
2074:
2067:
2060:
2058:
2056:
2052:
2048:
2044:
2038:
2036:
2032:
2028:
2023:
2021:
2017:
2004:
2000:
1996:
1992:
1988:
1987:
1982:
1975:
1972:
1968:
1964:
1958:
1955:
1951:
1946:
1944:
1942:
1938:
1934:
1930:
1925:
1923:
1921:
1919:
1915:
1912:
1907:
1904:
1892:
1885:
1881:
1875:
1872:
1868:
1864:
1858:
1855:
1851:
1845:
1842:
1835:
1831:
1827:
1823:
1819:
1815:
1808:
1805:
1801:
1797:
1791:
1788:
1784:
1780:
1776:
1770:
1767:
1761:
1759:
1755:
1753:
1752:reactor grade
1749:
1745:
1741:
1736:
1734:
1730:
1726:
1722:
1717:
1715:
1711:
1707:
1703:
1699:
1695:
1690:
1688:
1684:
1680:
1674:
1669:
1664:
1662:
1660:
1656:
1652:
1648:
1644:
1640:
1636:
1632:
1627:
1625:
1621:
1617:
1612:
1610:
1606:
1602:
1598:
1594:
1590:
1583:
1578:
1574:
1571:
1568:
1565:
1562:
1558:
1554:
1550:
1546:
1542:
1538:
1535:
1531:
1527:
1523:
1519:
1515:
1511:
1507:
1503:
1499:
1495:
1494:United States
1491:
1487:
1483:
1482:
1481:
1475:
1469:
1466:
1463:
1460:
1457:
1454:
1453:
1450:
1447:
1444:
1441:
1438:
1435:
1434:
1431:
1428:
1425:
1422:
1419:
1416:
1415:
1412:
1409:
1406:
1403:
1400:
1397:
1396:
1393:
1390:
1387:
1384:
1381:
1378:
1377:
1374:
1371:
1368:
1365:
1362:
1359:
1358:
1355:
1352:
1349:
1346:
1343:
1340:
1339:
1336:
1333:
1330:
1327:
1324:
1321:
1320:
1317:
1314:
1311:
1308:
1305:
1302:
1301:
1298:
1295:
1292:
1289:
1286:
1283:
1282:
1279:
1276:
1273:
1270:
1267:
1264:
1263:
1260:
1257:
1254:
1251:
1249:
1248:americium-243
1246:
1245:
1242:
1239:
1236:
1233:
1231:
1228:
1227:
1224:
1221:
1218:
1215:
1213:
1212:americium-241
1210:
1209:
1206:
1203:
1200:
1197:
1195:
1194:plutonium-242
1192:
1191:
1188:
1185:
1182:
1179:
1177:
1176:plutonium-241
1174:
1173:
1170:
1167:
1164:
1161:
1159:
1158:plutonium-240
1156:
1155:
1152:
1149:
1146:
1143:
1141:
1140:plutonium-239
1138:
1137:
1134:
1131:
1128:
1125:
1123:
1122:plutonium-238
1120:
1119:
1116:
1113:
1110:
1107:
1105:
1104:neptunium-237
1102:
1101:
1098:
1095:
1092:
1089:
1087:
1086:neptunium-236
1084:
1083:
1080:
1077:
1074:
1071:
1069:
1066:
1065:
1062:
1059:
1056:
1053:
1051:
1048:
1047:
1043:
1038:
1034:Critical mass
1033:
1028:
1025:
1024:
1021:
1019:
1013:
1011:
1007:
1003:
998:
994:
993:critical mass
988:
987:Critical mass
981:Critical mass
980:
978:
976:
972:
968:
964:
963:Neptunium-237
960:
956:
951:
949:
945:
941:
940:plutonium-239
937:
933:
929:
926:
921:
919:
915:
911:
907:
903:
899:
888:
883:
881:
876:
874:
869:
868:
866:
865:
860:
857:
855:
852:
850:
847:
845:
841:
838:
837:
834:
831:
829:
826:
820:
817:
815:
811:
808:
807:
804:
801:
799:
796:
794:
791:
789:
786:
784:
783:United States
780:
778:
774:
773:
772:
771:
768:
764:
759:
756:
754:
751:
749:
746:
744:
741:
739:
738:Proliferation
736:
734:
731:
729:
726:
724:
721:
719:
716:
714:
711:
710:
707:
704:
702:
699:
697:
694:
693:
690:
687:
685:
682:
680:
677:
675:
672:
670:
667:
665:
662:
660:
657:
656:
655:
654:
649:
645:
641:
640:
637:
633:
622:
618:
615:
611:
609:
605:
602:
598:
597:
594:
590:
578:
572:
569:
563:
561:
559:
557:
551:
543:
541:
540:15–24 Ma
538:
531:
529:
523:
510:
507:
505:
503:
496:
495:
487:
484:
482:
480:
478:
476:
475:
467:
465:
462:
460:
453:
447:
434:
429:
413:
409:
397:
395:
394:
391:24.1 ka
390:
383:
381:
379:
378:
374:
372:
360:
359:
355:
334:
330:
318:
316:
315:
311:
304:
297:
296:
293:
282:
280:
268:
267:
249:
246:
234:
228:
210:
207:
186:
183:
181:
179:
177:
174:
172:
170:
168:
162:
159:
152:
150:
147:
145:
143:
141:
135:
131:
128:
125:
123:
121:
116:
114:
112:
107:
105:
103:
98:
96:
95:
90:
89:
86:
82:
78:
72:
67:
62:
58:
54:
47:
42:
40:
35:
33:
28:
27:
22:
19:
2463:reprocessing
2456:
2442:
2392:February 28,
2390:. Retrieved
2386:the original
2376:
2364:. Retrieved
2350:
2338:. Retrieved
2334:
2324:
2312:. Retrieved
2305:the original
2288:
2254:
2250:
2236:
2226:September 5,
2224:. Retrieved
2219:
2210:
2198:
2183:
2171:. Retrieved
2154:
2141:
2104:
2100:
2072:
2046:
2007:. Retrieved
2003:the original
1990:
1986:Science News
1984:
1974:
1957:
1906:
1894:. Retrieved
1874:
1857:
1844:
1817:
1813:
1807:
1790:
1782:
1769:
1756:
1751:
1737:
1718:
1691:
1676:
1668:
1635:thallium-208
1628:
1613:
1587:
1573:South Africa
1479:
1014:
990:
952:
922:
897:
896:
844:South Africa
839:
823:(undeclared)
809:
775:
567:
486:1.33 Ma
286:
248:29–97 a
209:10–29 a
119:
110:
101:
93:
18:
2382:"Plutonium"
2362:. June 1994
2009:November 7,
1993:(17): 259.
1961:Chapter 5,
1896:October 13,
1867:quadrillion
1723:and French
1631:uranium-232
1616:thorium-232
1601:uranium-238
1557:North Korea
1492:(NPT): the
1456:einsteinium
1437:californium
1418:californium
1399:californium
1072:703,800,000
1068:uranium-235
1050:uranium-233
1010:uranium-235
1006:uranium-233
1002:uranium-238
955:uranium-233
936:uranium-235
833:North Korea
743:Disarmament
564:80 Ma
132:<0.001%
129:0.04–1.25%
61:decay chain
2485:Categories
2469:spent fuel
1820:(2): 299.
1762:References
1671:See also:
1347:15,600,000
1129:9.04–10.07
854:Kazakhstan
779:recognized
753:Opposition
651:Background
149:4–6 a
2501:Plutonium
2366:March 15,
2340:March 29,
2279:Q56853752
2271:1056-3466
2193:/TM-13517
1779:radon-222
1706:B Reactor
1391:16.1-16.6
1380:berkelium
1372:11.8-12.2
1361:berkelium
1350:6.94–7.06
1312:9.41–12.3
1108:2,144,000
1029:Half-life
1018:actinides
967:americium
932:potential
910:Plutonium
748:Terrorism
733:Espionage
728:Blackmail
723:Arms race
619:þ,
606:ƒ,
289:half-life
66:Half-life
57:Actinides
2419:Archived
2275:Wikidata
1775:polonium
1549:Pakistan
1039:Diameter
997:isotopes
928:isotopes
849:Belarus
828:Pakistan
713:Arsenals
684:Delivery
2506:Uranium
2314:May 10,
2173:May 17,
2136:, p. 16
1822:Bibcode
1689:plant.
1597:fissile
1555:), and
1528:), and
1512:), the
1331:39–70.1
1296:12.4–16
1293:13.5–30
1274:7.34–10
1255:180–280
1198:375,000
1132:9.5–9.9
1090:154,000
1054:159,200
1026:Nuclide
925:fissile
914:uranium
859:Ukraine
701:Workers
696:Effects
679:Testing
669:Warfare
664:History
608:fissile
126:4.5–7%
69:range (
2449:
2431:Nature
2277:
2269:
2047:Nature
1869:years.
1740:fizzle
1721:Magnox
1714:burnup
1694:Pu-239
1683:decays
1655:Pu-238
1651:Pu-240
1605:masses
1567:Israel
1522:France
1506:Russia
1342:curium
1323:curium
1304:curium
1285:curium
1266:curium
1201:75–100
1144:24,110
840:Former
821:
819:Israel
810:Others
798:France
788:Russia
758:Winter
706:Ethics
674:Design
616:(NORM)
2308:(PDF)
2301:(PDF)
2164:(PDF)
2069:(PDF)
1887:(PDF)
1541:India
1530:China
1461:0.755
1334:18–21
1315:11–12
1277:10–11
1258:30–35
1240:11–13
1222:20–23
1219:55–77
1216:432.2
1204:19–21
923:Only
814:India
803:China
689:Yield
85:yield
2447:ISBN
2394:2010
2368:2007
2342:2014
2316:2010
2267:ISSN
2228:2011
2191:ORNL
2175:2017
2011:2013
1898:2011
1783:days
1725:UNGG
1534:1964
1526:1960
1518:1952
1464:9.89
1458:-254
1445:2.73
1439:-252
1426:5.46
1420:-251
1401:-249
1382:-249
1369:75.7
1366:1380
1363:-247
1344:-247
1328:4760
1325:-246
1309:8500
1306:-245
1290:18.1
1287:-244
1271:29.1
1268:-243
1252:7370
1237:9–14
1186:10.5
1180:14.3
1162:6561
1126:87.7
1044:Ref
1041:(cm)
1036:(kg)
1008:and
938:and
912:and
2466:LWR
2335:PBS
2259:doi
2205:FAQ
2109:doi
1995:doi
1991:162
1830:doi
1647:cf.
1618:by
1547:),
1520:),
1504:),
1467:7.1
1448:6.9
1442:2.6
1429:8.5
1423:900
1404:351
1388:192
1385:0.9
1353:9.9
1234:141
1150:9.9
1096:8.7
1031:(y)
973:in
961:).
777:NPT
576:Th
555:Pu
536:Cm
520:Pd
515:Zr
501:Np
492:Cs
472:Se
458:Pu
451:Cm
444:Sn
439:Tc
417:Np
407:Pa
402:Th
388:Pu
370:Cm
365:Cm
353:Am
348:Cm
343:Th
338:Pu
328:Bk
323:Ra
309:Cf
302:Am
278:Am
273:Cf
264:Sn
259:Sm
254:Cs
244:Cm
239:Pu
225:Cd
220:Kr
215:Sr
205:Ac
200:Cf
195:Pu
190:Cm
166:Bk
157:Eu
139:Ra
122:+ 3
113:+ 2
104:+ 1
83:by
79:of
59:by
2487::
2455:.
2425:,
2358:.
2333:.
2273:.
2265:.
2255:22
2253:.
2249:.
2218:.
2166:.
2123:^
2105:39
2103:.
2099:.
2081:^
2071:.
2054:^
2045:,
2034:^
2019:^
1989:.
1983:.
1965:,
1940:^
1931:,
1917:^
1889:.
1852:".
1828:.
1818:71
1816:.
1716:.
1641:.
1607:.
1183:12
1168:15
1165:40
1147:10
1114:18
1111:60
1078:17
1075:52
1060:11
1057:15
977:.
950:.
588:U
583:U
548:I
527:U
427:U
422:U
232:U
73:)
2396:.
2370:.
2344:.
2318:.
2283:.
2281:.
2261::
2230:.
2177:.
2117:.
2111::
2013:.
1997::
1935:.
1900:.
1836:.
1832::
1824::
1802:.
1563:)
1536:)
1532:(
1524:(
1516:(
1508:(
1496:(
1410:9
1407:6
1093:7
886:e
879:t
872:v
120:n
118:4
111:n
109:4
102:n
100:4
94:n
92:4
81:U
71:a
45:e
38:t
31:v
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
