796:
1066:). Each radium-224 atom undergoes a decay process producing 6 daughter atoms. During this process, 4 alpha particles are emitted. The range of an alpha particle—up to 100 microns—is insufficient to cover the width of many tumors. However, radium-224's daughter atoms can diffuse up to 2–3 mm in the tissue, thus creating a "kill region" with enough radiation to potentially destroy an entire tumor, if the seeds are placed appropriately. Radium-224's half-life is short enough at 3.6 days to produce a rapid clinical effect while avoiding the risk of radiation damage due to overexposure. At the same time, the half-life is long enough to allow for handling and shipping the seeds to a cancer treatment center at any location across the globe.
645:
391:
890:
402:
768:
788:
569:. In this process, three charged particles are produced from the event instead of the normal two, with the smallest of the charged particles most probably (90% probability) being an alpha particle. Such alpha particles are termed "long range alphas" since at their typical energy of 16 MeV, they are at far higher energy than is ever produced by alpha decay. Ternary fission happens in both neutron-induced fission (the
878:
that were deflected was akin to shooting a fifteen-inch shell at tissue paper only to have it bounce off, again assuming the "plum pudding" theory was correct. It was determined that the atom's positive charge was concentrated in a small area in its center, making the positive charge dense enough to deflect any positively charged alpha particles that came close to what was later termed the nucleus.
795:
40:
2364:
731:
relative biological effectiveness is considered to be 20, the carcinogenic potential (in terms of lung cancer) of alpha radiation appears to be consistent with that reported for doses of external gamma radiation i.e. a given dose of alpha-particles inhaled presents the same risk as a 20-times higher dose of gamma radiation. The powerful alpha emitter
553:. This is allowed by the wave nature of matter, which allows the alpha particle to spend some of its time in a region so far from the nucleus that the potential from the repulsive electromagnetic force has fully compensated for the attraction of the nuclear force. From this point, alpha particles can escape.
995:
is passed through that ionized air. Smoke particles from fire that enter the air gap reduce the current flow, sounding the alarm. The isotope is extremely dangerous if inhaled or ingested, but the danger is minimal if the source is kept sealed. Many municipalities have established programs to collect
1053:
mimetic. Radium-223 (as radium-223 dichloride) can be infused into a cancer patient's veins, after which it migrates to parts of the bone where there is rapid turnover of cells due to the presence of metastasized tumors. Once within the bone, Ra-223 emits alpha radiation that can destroy tumor cells
877:
It was found that some of the alpha particles were deflected at much larger angles than expected (at a suggestion by
Rutherford to check it) and some even bounced almost directly back. Although most of the alpha particles went straight through as expected, Rutherford commented that the few particles
1042:
are presently being used in three different ways to eradicate cancerous tumors: as an infusible radioactive treatment targeted to specific tissues (radium-223), as a source of radiation inserted directly into solid tumors (radium-224), and as an attachment to an tumor-targeting molecule, such as an
713:
Due to the short range of absorption and inability to penetrate the outer layers of skin, alpha particles are not, in general, dangerous to life unless the source is ingested or inhaled. Because of this high mass and strong absorption, if alpha-emitting radionuclides do enter the body (upon being
678:
With a typical kinetic energy of 5 MeV; the speed of emitted alpha particles is 15,000 km/s, which is 5% of the speed of light. This energy is a substantial amount of energy for a single particle, but their high mass means alpha particles have a lower speed than any other common type of
310:
are also usually of much higher energy than those produced by nuclear decay processes, and thus may be highly penetrating and able to traverse the human body and also many metres of dense solid shielding, depending on their energy. To a lesser extent, this is also true of very high-energy helium
730:
damage from alpha particles is anywhere from 10 to 1000 times greater than that caused by an equivalent amount of gamma or beta radiation, with the average being set at 20 times. A study of
European nuclear workers exposed internally to alpha radiation from plutonium and uranium found that when
1058:
which has metastasized to the bone. Radionuclides infused into the circulation are able to reach sites that are accessible to blood vessels. This means, however, that the interior of a large tumor that is not vascularized (i.e. is not well penetrated by blood vessels) may not be effectively
811:(working in Paris) separated radiation into three types: eventually named alpha, beta, and gamma by Rutherford, based on penetration of objects and deflection by a magnetic field. Alpha rays were defined by Rutherford as those having the lowest penetration of ordinary objects.
881:
Prior to this discovery, it was not known that alpha particles were themselves atomic nuclei, nor was the existence of protons or neutrons known. After this discovery, J.J. Thomson's "plum pudding" model was abandoned, and
Rutherford's experiment led to the
2225:
Tafreshi, Narges K.; Doligalski, Michael L.; Tichacek, Christopher J.; Pandya, Darpan N.; Budzevich, Mikalai M.; El-Haddad, Ghassan; Khushalani, Nikhil I.; Moros, Eduardo G.; McLaughlin, Mark L.; Wadas, Thaddeus J.; Morse, David L. (26 November 2019).
690:
Because of their charge and large mass, alpha particles are easily absorbed by materials, and they can travel only a few centimetres in air. They can be absorbed by tissue paper or by the outer layers of human skin. They typically penetrate skin about
814:
Rutherford's work also included measurements of the ratio of an alpha particle's mass to its charge, which led him to the hypothesis that alpha particles were doubly charged helium ions (later shown to be bare helium nuclei). In 1909,
1069:
Targeted alpha therapy for solid tumors involves attaching an alpha-particle-emitting radionuclide to a tumor-targeting molecule such as an antibody, that can be delivered by intravenous administration to a cancer patient.
671:(mega-electron-volts), corresponding to extremely long and extremely short half-lives of alpha-emitting nuclides, respectively. The energies and ratios are often distinct and can be used to identify specific nuclides as in
541:
from the strong force inside the nucleus (this well involves escaping the strong force to go up one side of the well, which is followed by the electromagnetic force causing a repulsive push-off down the other side).
480:
elements. Unlike other types of decay, alpha decay as a process must have a minimum-size atomic nucleus that can support it. The smallest nuclei that have to date been found to be capable of alpha emission are
588:
as a form of radioactive decay. In both induced and spontaneous fission, the higher energies available in heavy nuclei result in long range alphas of higher energy than those from alpha decay.
921:). Further experimentation showed the protons to be coming from the nitrogen component of air, and the reaction was deduced to be a transmutation of nitrogen into oxygen in the reaction
917:, but when Rutherford projected alpha particles from alpha decay into air, he discovered this produced a new type of radiation which proved to be hydrogen nuclei (Rutherford named these
660:
is mildly dependent on the half-life for the emission process, with many orders of magnitude differences in half-life being associated with energy changes of less than 50%, shown by the
823:
finally proved that alpha particles were indeed helium ions. To do this they collected and purified the gas emitted by radium, a known alpha particle emitter, in a glass tube. An
965:
partner of the helium nucleus, also known as the anti-alpha. The experiment used gold ions moving at nearly the speed of light and colliding head on to produce the antiparticle.
667:
The energy of alpha particles emitted varies, with higher energy alpha particles being emitted from larger nuclei, but most alpha particles have energies of between 3 and 7
827:
discharge inside the tube produced light. Subsequent study of the spectra of this light showed that the gas was helium and thus the alpha particles were indeed the helium ions.
1096:'s DRAM chips. The discovery led to strict control of radioactive elements in the packaging of semiconductor materials, and the problem is largely considered to be solved.
752:
2119:
Silson, John E. "Hazards in the use of radioactive static eliminators and their control." American
Journal of Public Health and the Nations Health 40.8 (1950): 943-952.
341:
361:
937:
To the adjacent pictures: According to the energy-loss curve by Bragg, it is recognizable that the alpha particle indeed loses more energy on the end of the trace.
1275:
1245:
1215:
874:" model of the atom was correct, the positively charged alpha particles would be only slightly deflected, if at all, by the dispersed positive charge predicted.
2782:
489:, not counting beta-delayed alpha emission of some lighter elements. The alpha decay sometimes leaves the parent nucleus in an excited state; the emission of a
1664:
Little, John B.; Kennedy, Ann R.; McGandy, Robert B. (1985). "Effect of Dose Rate on the
Induction of Experimental Lung Cancer in Hamsters by α Radiation".
866:, a narrow beam of alpha particles was established, passing through very thin (a few hundred atoms thick) gold foil. The alpha particles were detected by a
2767:
996:
and dispose of old smoke detectors, to keep them out of the general waste stream. However the US EPA says they "may be thrown away with household garbage".
1063:
648:
Example selection of radioactive nuclides with main emitted alpha particle energies plotted against their atomic number. Each nuclide has a distinct
2878:
616:
Helium nuclei may participate in nuclear reactions in stars, and occasionally and historically these have been referred to as alpha reactions (see
367:
determined that "the alpha particle, after it has lost its positive charge, is a Helium atom". Alpha radiation consists of particles equivalent to
905:
The trace of a single alpha particle obtained by nuclear physicist
Wolfhart Willimczik with his spark chamber specially made for alpha particles.
2736:
323:
in reporting his studies of the properties of uranium radiation. The radiation appeared to have two different characters, the first he called "
2068:
2347:
2287:
1494:
1360:
1313:
1000:
2762:
2731:
2676:
2089:
Schulman, Fred. "Isotopes and
Isotope Thermoelectric Generators." Space Power Systems Advanced Technology Conference. No. N67-10265. 1966.
2395:
1611:
whenever their energy is > 64 keV, which it commonly is. Neutron velocity from nuclear reactions ranges from about 6%
2711:
902:
433:
of the atom goes down by two, as a result of the loss of two protons – the atom becomes a new element. Examples of this sort of
220:. The symbol for the alpha particle is α or α. Because they are identical to helium nuclei, they are also sometimes written as He or
1568:
708:
2099:
2777:
1139:
561:
Especially energetic alpha particles deriving from a nuclear process are produced in the relatively rare (one in a few hundred)
950:
913:
of one element to another. Transmutation of elements from one to another had been understood since 1901 as a result of natural
1856:
958:
534:
240:). Once the ion gains electrons from its environment, the alpha particle becomes a normal (electrically neutral) helium atom
855:
1062:
Radium-224 is a radioactive atom that is utilized as a source of alpha radiation in a cancer treatment device called DaRT (
2843:
2031:
1085:
2868:
2599:
1344:
672:
649:
390:
632:
In addition, extremely high energy helium nuclei sometimes referred to as alpha particles make up about 10 to 12% of
2831:
2686:
2659:
2368:
870:
screen, which emits a flash of light upon an alpha particle collision. Rutherford hypothesized that, assuming the "
371:(He) which can gain electrons from passing through matter. This mechanism is the origin of terrestrial helium gas.
1717:"Risk of lung cancer mortality in nuclear workers from internal exposure to alpha particle-emitting radionuclides"
1511:
909:
In 1917, Rutherford went on to use alpha particles to accidentally produce what he later understood as a directed
2716:
2569:
954:
1431:
Proceedings of the Royal
Society of London. Series A, Containing Papers of a Mathematical and Physical Character
2654:
2428:
2564:
779:, is halted by an aluminium plate. Gamma radiation is eventually absorbed as it penetrates a dense material.
2594:
2388:
510:
168:
661:
2873:
2835:
2746:
2420:
1393:, Series 5, vol. 47, no. 284, pages 109–163. Rutherford named γ rays on page 177 of: E. Rutherford (1903)
2130:
2839:
2574:
1629:
Christensen, D. M.; Iddins, C. J.; Sugarman, S. L. (2014). "Ionizing radiation injuries and illnesses".
1187:
910:
889:
722:. It is the most strongly ionizing, and with large enough doses can cause any or all of the symptoms of
514:
434:
401:
2696:
2584:
2541:
2491:
2296:
2183:
1949:
1775:
1673:
1523:
1438:
1305:
756:
617:
605:
306:
are three times as energetic and penetrate three times as far. The helium nuclei that form 10–12% of
2813:
2772:
2691:
2604:
2060:
1848:
1330:
723:
718:
for high-quality X-ray images prior to the 1950s), alpha radiation is the most destructive form of
585:
64:
1764:
Radford, Edward P.; Hunt, Vilma R. (1964). "Polonium-210: A Volatile
Radioelement in Cigarettes".
2808:
2629:
2609:
2589:
2473:
2381:
2312:
2207:
2013:
1995:
1973:
1939:
1925:
1873:
1799:
1689:
1464:
1126:
1018:
946:
871:
851:
748:
719:
280:
276:
1818:
212:
but may also be produced in other ways. Alpha particles are named after the first letter in the
644:
2701:
2579:
2516:
2481:
2343:
2267:
2249:
2199:
2152:
1965:
1893:
1852:
1791:
1766:
1746:
1697:
1646:
1574:
1564:
1539:
1490:
1456:
1394:
1387:
1366:
1356:
1309:
1180:
914:
816:
804:
684:
546:
320:
284:
256:
153:
326:
2706:
2304:
2257:
2239:
2191:
2142:
2005:
1986:
1957:
1930:
1885:
1783:
1736:
1728:
1681:
1638:
1531:
1446:
1149:
992:
931:
835:
570:
522:
346:
299:
2285:
May, T. C.; Woods, M. H. (1979). "Alpha-particle-induced soft errors in dynamic memories".
2172:"Treatment of solid tumors by interstitial release of recoiling short-lived alpha emitters"
767:
2863:
2818:
2803:
2619:
2531:
2521:
1592:
1144:
1055:
1007:. Alpha decay is much more easily shielded against than other forms of radioactive decay.
839:
566:
562:
549:
effect allows alphas to escape even though they do not have enough energy to overcome the
526:
303:
147:
2300:
2187:
1953:
1779:
1677:
1527:
1442:
2666:
2624:
2614:
2536:
2526:
2262:
2227:
1741:
1716:
1535:
1352:
980:
863:
843:
824:
744:
696:
538:
272:
260:
213:
205:
162:
84:
2195:
1267:
787:
2857:
2741:
2501:
2486:
2339:
1977:
1386:
Rutherford distinguished and named α and β rays on page 116 of: E. Rutherford (1899)
1348:
1116:
1110:
1105:
1039:
1008:
984:
847:
680:
621:
550:
530:
518:
486:
430:
406:
395:
2316:
1803:
1410:
Rutherford, Ernest; Geiger, Hans (2014). "The Charge and Nature of the α-Particle".
2721:
2681:
2546:
2211:
2017:
1334:
1154:
1026:
1022:
867:
820:
808:
735:(a milligram of Po emits as many alpha particles per second as 4.215 grams of
732:
525:
between the alpha particle and the rest of the nucleus, which both have a positive
136:
1910:
Magazine "nuclear energy" (III/18 (203) special edition, Volume 10, Issue 2 /1967.
1237:
775:
nucleus and is readily stopped by a sheet of paper. Beta radiation, consisting of
2373:
1787:
1732:
1207:
2463:
1329:
Bohan, Elise; Dinwiddie, Robert; Challoner, Jack; Stuart, Colin; Harvey, Derek;
1054:
within a 100-micron distance. This approach has been in use since 2013 to treat
1004:
894:
859:
740:
657:
601:
574:
482:
477:
457:
422:
414:
385:
364:
209:
46:
1878:
The London, Edinburgh, and Dublin
Philosophical Magazine and Journal of Science
2511:
2458:
2244:
1889:
1642:
1395:"The magnetic and electric deviation of the easily absorbed rays from radium,"
1121:
1089:
1079:
1046:
988:
962:
883:
736:
727:
715:
692:
633:
506:
394:
A physicist observes alpha particles from the decay of a polonium source in a
307:
2253:
2170:
Arazi, L.; Cooks, T.; Schmidt, M.; Keisari, Y.; Kelson, I. (21 August 2007).
1897:
1543:
1460:
1370:
608:. Convention is that they are not normally referred to as "alpha particles".
363:
radiation". After five years of additional experimental work, Rutherford and
2798:
2671:
2506:
2453:
2443:
2404:
2308:
2171:
1578:
1174:
1168:
1162:
1049:
is an alpha emitter that is naturally attracted to the bone because it is a
597:
490:
2271:
2203:
2156:
1969:
1795:
1750:
1650:
1451:
901:
2363:
2147:
1701:
1338:
17:
2448:
2433:
1558:
1134:
1130:
776:
772:
581:
469:
268:
255:
Alpha particles have a net spin of zero. When produced in standard alpha
237:
202:
198:
54:
2009:
1961:
1337:; Hubbard, Ben; Parker, Phillip; et al. (Writers) (February 2016).
39:
2726:
2035:
1693:
1050:
578:
465:
461:
442:
438:
426:
194:
897:) in air for typical alpha particle emitted through radioactive decay.
2131:"Alpha emitter radium-223 and survival in metastatic prostate cancer"
1468:
1426:
925:
918:
831:
494:
473:
446:
190:
1685:
2551:
2438:
2000:
1944:
1596:
1093:
900:
888:
794:
786:
766:
643:
636:. The mechanisms of cosmic ray production continue to be debated.
450:
400:
389:
217:
69:
2228:"Development of Targeted Alpha Particle Therapy for Solid Tumors"
2032:"Antihelium-4: Physicists nab new record for heaviest antimatter"
1388:"Uranium radiation and the electrical conduction produced by it,"
1268:"2022 CODATA Value: alpha particle mass energy equivalent in MeV"
1012:
780:
418:
292:
2377:
1874:"XXI. The nature of the α particle from radioactive substances"
668:
288:
264:
233:
1928:) (2011). "Observation of the antimatter helium-4 nucleus".
1011:, a source of alpha particles, requires only 2.5 mm of
38:
27:
Ionizing radiation particle of two protons and two neutrons
537:, alpha particles do not have enough energy to escape the
456:
Alpha particles are commonly emitted by all of the larger
783:
is good at absorbing gamma radiation, due to its density.
596:
Energetic helium nuclei (helium ions) may be produced by
1487:
Inward bound: of matter and forces in the physical world
886:
and later the modern wave-mechanical model of the atom.
584:
nuclides (i.e., heavy atoms capable of fission) undergo
417:
of heavier (mass number of at least 104) atoms. When an
1272:
The NIST Reference on Constants, Units, and Uncertainty
1242:
The NIST Reference on Constants, Units, and Uncertainty
1212:
The NIST Reference on Constants, Units, and Uncertainty
807:(working in McGill University in Montreal, Canada) and
2129:
Parker, C.; Nilsson, S.; Heinrich, D. (18 July 2013).
830:
Because alpha particles occur naturally, but can have
513:
responsible for alpha decay are a balance between the
349:
329:
1603:). Beta particles often move at a large fraction of
1080:
Soft error § Alpha particles from package decay
2791:
2755:
2642:
2472:
2419:
2412:
799:
Dispersing of alpha particles on a thin metal sheet
714:inhaled, ingested, or injected, as with the use of
421:emits an alpha particle in alpha decay, the atom's
409:(after injection of an artificial source radon-220)
343:
radiation" and the more penetrating one he called "
161:
146:
83:
75:
63:
53:
1512:"Radiogenic Origin of the Helium Isotopes in Rock"
1113:(Also known as alpha-capture, or the alpha-ladder)
791:An alpha particle is deflected by a magnetic field
573:that happens in a nuclear reactor), and also when
355:
335:
1412:The Collected Papers of Lord Rutherford of Nelson
1382:
1380:
1025:, an alpha emitter, to ionize air, allowing the "
1557:Firestone, Richard B.; Baglin, Coral M. (1999).
1015:shielding to protect against unwanted radiation.
999:Alpha decay can provide a safe power source for
208:. They are generally produced in the process of
2055:
2053:
838:, study of them led to much early knowledge of
751:. Po was used to kill Russian dissident and ex-
425:decreases by four due to the loss of the four
2389:
1489:(Reprint ed.). Oxford: Clarendon Press
1238:"2022 CODATA Value: alpha particle mass in u"
842:. Rutherford used alpha particles emitted by
8:
1480:
1478:
1092:" were linked to alpha particles in 1978 in
983:contain a small amount of the alpha emitter
656:The energy of the alpha particle emitted in
413:The best-known source of alpha particles is
32:
1872:Rutherford, E.; Royds, T. (February 1909).
1843:Hellemans, Alexander; Bunch, Bryan (1988).
1819:"Radiation Poisoning Killed Ex-Russian Spy"
1631:Emergency Medicine Clinics of North America
405:Alpha radiation detected in an isopropanol
2416:
2396:
2382:
2374:
1516:Annals of the New York Academy of Sciences
1400:, Series 6, vol. 5, no. 26, pages 177–187.
1064:diffusing alpha emitters radiation therapy
311:nuclei produced by particle accelerators.
2261:
2243:
2146:
2061:"Americium in Ionization Smoke Detectors"
1999:
1943:
1740:
1450:
1427:"The Charge and Nature of the α-Particle"
854:of the atom was fundamentally flawed. In
348:
328:
1208:"2022 CODATA Value: alpha particle mass"
1043:antibody to a tumor-associated antigen.
319:The term "alpha particle" was coined by
2334:Tipler, Paul; Llewellyn, Ralph (2002).
1295:
1293:
1199:
2737:Wireless electronic devices and health
2100:"Static Eliminators (1960s and 1980s)"
2071:from the original on 27 September 2023
1001:radioisotope thermoelectric generators
945:In 2011, members of the international
501:Mechanism of production in alpha decay
31:
2288:IEEE Transactions on Electron Devices
1715:Grellier, James; et al. (2017).
1425:Rutherford, E.; Geiger, Hans (1908).
7:
2763:List of civilian radiation accidents
2732:Wireless device radiation and health
2727:Biological dose units and quantities
2677:Electromagnetic radiation and health
2065:U.S. Environmental Protection Agency
739:) is suspected of playing a role in
529:, but which is kept in check by the
1615:for fission to as much as 17%
1599:) they move at the speed of light (
259:, alpha particles generally have a
2712:Radioactivity in the life sciences
1536:10.1111/j.1749-6632.1955.tb35366.x
236:with a +2 charge (missing its two
25:
1817:Cowell, Alan (24 November 2006).
1563:(8th ed.). New York: Wiley.
1059:eradicated by the radioactivity.
856:Rutherford's gold foil experiment
709:Relative biological effectiveness
287:(stopped by a few centimetres of
2362:
1140:List of alpha emitting materials
991:air within a small gap. A small
834:high enough to participate in a
437:by alpha decay are the decay of
2879:Subatomic particles with spin 0
2176:Physics in Medicine and Biology
2135:New England Journal of Medicine
1510:Morrison, P.; Pine, J. (1955).
1074:Alpha radiation and DRAM errors
951:Relativistic Heavy Ion Collider
521:. Alpha decay results from the
1414:. Routledge. pp. 109–120.
959:Brookhaven National Laboratory
930:This was the first discovered
1:
271:in the vicinity of 4% of the
1788:10.1126/science.143.3603.247
1733:10.1097/EDE.0000000000000684
1302:Introductory Nuclear Physics
1086:dynamic random access memory
1029:" to more rapidly dissipate.
771:Alpha radiation consists of
763:History of discovery and use
369:doubly-ionized helium nuclei
2600:Cosmic background radiation
2196:10.1088/0031-9155/52/16/021
429:in the alpha particle. The
2895:
2829:
2687:Lasers and aviation safety
1591:N.B. Since gamma rays are
1300:Krane, Kenneth S. (1988).
1077:
858:conducted by his students
706:
383:
2827:
2717:Radioactive contamination
2570:Electromagnetic radiation
2560:
2245:10.3390/molecules24234314
1890:10.1080/14786440208636599
1845:The Timetables of Science
1643:10.1016/j.emc.2013.10.002
1347:(1st American ed.).
955:U.S. Department of Energy
37:
2830:See also the categories
2768:1996 Costa Rica accident
2429:Acoustic radiation force
1084:In computer technology,
511:fundamental interactions
493:then removes the excess
2742:Radiation heat-transfer
2595:Gravitational radiation
2309:10.1109/T-ED.1979.19370
757:Alexander V. Litvinenko
726:. It is estimated that
336:{\displaystyle \alpha }
2783:1990 Zaragoza accident
2778:1984 Moroccan accident
2747:Linear energy transfer
2421:Non-ionizing radiation
1607:, and exceed 60%
1485:Pais, Abraham (2002).
1452:10.1098/rspa.1908.0066
1398:Philosophical Magazine
1391:Philosophical Magazine
987:. The alpha particles
906:
898:
800:
792:
784:
695:, equivalent to a few
653:
410:
398:
357:
356:{\displaystyle \beta }
337:
197:bound together into a
43:
2773:1987 Goiânia accident
2575:Synchrotron radiation
2565:Earth's energy budget
2547:Radioactive materials
2542:Particle accelerators
2371:at Wikimedia Commons
2148:10.1056/NEJMoa1213755
1306:John Wiley & Sons
1188:Rutherford scattering
911:nuclear transmutation
904:
892:
798:
790:
770:
647:
640:Energy and absorption
606:particle accelerators
515:electromagnetic force
435:nuclear transmutation
404:
393:
358:
338:
59:2 protons, 2 neutrons
42:
2844:Radiation protection
2697:Radiation protection
2585:Black-body radiation
2492:Background radiation
2407:(physics and health)
2067:. 27 November 2018.
1849:Simon & Schuster
1331:Wragg-Sykes, Rebecca
1308:. pp. 246–269.
803:In 1899, physicists
618:triple-alpha process
612:Solar core reactions
347:
327:
275:. They are a highly
232:indicating a helium
148:Electric charge
2814:Radiation hardening
2756:Radiation incidents
2692:Medical radiography
2651:Radiation syndrome
2605:Cherenkov radiation
2301:1979ITED...26....2M
2188:2007PMB....52.5025A
2010:10.1038/nature10264
1994:(7356): 412. 2011.
1962:10.1038/nature10079
1954:2011Natur.473..353S
1780:1964Sci...143..247R
1678:1985RadR..103..293L
1528:1955NYASA..62...71M
1443:1908RSPSA..81..162R
1155:Radioactive isotope
941:Anti-alpha particle
724:radiation poisoning
586:spontaneous fission
298:However, so-called
34:
2869:Ionizing radiation
2809:Radioactive source
2630:Radiation exposure
2610:Askaryan radiation
2590:Particle radiation
2474:Ionizing radiation
1926:STAR collaboration
1823:The New York Times
1666:Radiation Research
1019:Static eliminators
947:STAR collaboration
907:
899:
852:Plum pudding model
801:
793:
785:
720:ionizing radiation
703:Biological effects
673:alpha spectrometry
662:Geiger–Nuttall law
654:
547:quantum tunnelling
411:
399:
353:
333:
281:particle radiation
44:
2851:
2850:
2832:Radiation effects
2702:Radiation therapy
2638:
2637:
2580:Thermal radiation
2517:Neutron radiation
2482:Radioactive decay
2367:Media related to
2349:978-0-7167-4345-3
1774:(3603): 247–249.
1560:Table of isotopes
1496:978-0-19-851997-3
1362:978-1-4654-5443-0
1315:978-0-471-80553-3
1181:Epsilon radiation
1129:, the nucleus of
915:radioactive decay
817:Ernest Rutherford
805:Ernest Rutherford
535:classical physics
523:Coulomb repulsion
476:, as well as the
321:Ernest Rutherford
285:penetration depth
257:radioactive decay
189:, consist of two
176:
175:
16:(Redirected from
2886:
2792:Related articles
2707:Radiation damage
2532:Nuclear reactors
2417:
2398:
2391:
2384:
2375:
2366:
2353:
2338:(4th ed.).
2321:
2320:
2282:
2276:
2275:
2265:
2247:
2222:
2216:
2215:
2167:
2161:
2160:
2150:
2126:
2120:
2117:
2111:
2110:
2108:
2106:
2096:
2090:
2087:
2081:
2080:
2078:
2076:
2057:
2048:
2047:
2045:
2043:
2028:
2022:
2021:
2003:
1981:
1947:
1920:Agakishiev, H.;
1917:
1911:
1908:
1902:
1901:
1869:
1863:
1862:
1840:
1834:
1833:
1831:
1829:
1814:
1808:
1807:
1761:
1755:
1754:
1744:
1712:
1706:
1705:
1661:
1655:
1654:
1626:
1620:
1589:
1583:
1582:
1554:
1548:
1547:
1507:
1501:
1500:
1482:
1473:
1472:
1454:
1437:(546): 162–173.
1422:
1416:
1415:
1407:
1401:
1384:
1375:
1374:
1326:
1320:
1319:
1297:
1288:
1287:
1285:
1283:
1264:
1258:
1257:
1255:
1253:
1234:
1228:
1227:
1225:
1223:
1204:
1150:Particle physics
1034:Cancer treatment
932:nuclear reaction
836:nuclear reaction
679:radiation, e.g.
571:nuclear reaction
362:
360:
359:
354:
342:
340:
339:
334:
300:long-range alpha
263:of about 5
251:
249:
248:
231:
229:
228:
142:
133:
131:
128:
122:
119:
117:
114:
111:
105:
102:
100:
96:
93:
35:
21:
2894:
2893:
2889:
2888:
2887:
2885:
2884:
2883:
2854:
2853:
2852:
2847:
2846:
2823:
2819:Havana syndrome
2804:Nuclear physics
2787:
2751:
2644:
2634:
2620:Unruh radiation
2556:
2537:Nuclear weapons
2522:Nuclear fission
2468:
2408:
2402:
2369:Alpha particles
2360:
2350:
2333:
2330:
2328:Further reading
2325:
2324:
2284:
2283:
2279:
2224:
2223:
2219:
2182:(16): 5025–42.
2169:
2168:
2164:
2128:
2127:
2123:
2118:
2114:
2104:
2102:
2098:
2097:
2093:
2088:
2084:
2074:
2072:
2059:
2058:
2051:
2041:
2039:
2038:. 24 April 2011
2030:
2029:
2025:
1983:
1938:(7347): 353–6.
1919:
1918:
1914:
1909:
1905:
1884:(98): 281–286.
1871:
1870:
1866:
1859:
1851:. p. 411.
1842:
1841:
1837:
1827:
1825:
1816:
1815:
1811:
1763:
1762:
1758:
1714:
1713:
1709:
1686:10.2307/3576584
1663:
1662:
1658:
1628:
1627:
1623:
1593:electromagnetic
1590:
1586:
1571:
1556:
1555:
1551:
1509:
1508:
1504:
1497:
1484:
1483:
1476:
1424:
1423:
1419:
1409:
1408:
1404:
1385:
1378:
1363:
1345:David Christian
1328:
1327:
1323:
1316:
1299:
1298:
1291:
1281:
1279:
1266:
1265:
1261:
1251:
1249:
1236:
1235:
1231:
1221:
1219:
1206:
1205:
1201:
1196:
1145:Nuclear physics
1102:
1082:
1076:
1056:prostate cancer
1038:Alpha-emitting
1036:
981:smoke detectors
976:
971:
943:
928:
840:nuclear physics
765:
749:tobacco smoking
711:
705:
642:
630:
614:
594:
567:ternary fission
563:nuclear fission
559:
557:Ternary fission
527:electric charge
505:In contrast to
503:
460:nuclei such as
388:
382:
377:
345:
344:
325:
324:
317:
304:ternary fission
302:particles from
247:
244:
243:
242:
241:
227:
224:
223:
222:
221:
201:identical to a
187:alpha radiation
179:Alpha particles
135:
129:
126:
124:
123:
120:
115:
112:
109:
107:
106:
103:
98:
94:
91:
89:
49:
28:
23:
22:
15:
12:
11:
5:
2892:
2890:
2882:
2881:
2876:
2871:
2866:
2856:
2855:
2849:
2848:
2828:
2825:
2824:
2822:
2821:
2816:
2811:
2806:
2801:
2795:
2793:
2789:
2788:
2786:
2785:
2780:
2775:
2770:
2765:
2759:
2757:
2753:
2752:
2750:
2749:
2744:
2739:
2734:
2729:
2724:
2719:
2714:
2709:
2704:
2699:
2694:
2689:
2684:
2679:
2674:
2669:
2667:Health physics
2664:
2663:
2662:
2657:
2648:
2646:
2640:
2639:
2636:
2635:
2633:
2632:
2627:
2625:Dark radiation
2622:
2617:
2615:Bremsstrahlung
2612:
2607:
2602:
2597:
2592:
2587:
2582:
2577:
2572:
2567:
2561:
2558:
2557:
2555:
2554:
2549:
2544:
2539:
2534:
2529:
2527:Nuclear fusion
2524:
2519:
2514:
2509:
2504:
2499:
2497:Alpha particle
2494:
2489:
2484:
2478:
2476:
2470:
2469:
2467:
2466:
2461:
2456:
2451:
2446:
2441:
2436:
2431:
2425:
2423:
2414:
2410:
2409:
2403:
2401:
2400:
2393:
2386:
2378:
2359:
2358:External links
2356:
2355:
2354:
2348:
2336:Modern Physics
2329:
2326:
2323:
2322:
2277:
2217:
2162:
2141:(3): 213–223.
2121:
2112:
2091:
2082:
2049:
2023:
1912:
1903:
1864:
1857:
1835:
1809:
1756:
1727:(5): 675–684.
1707:
1656:
1621:
1584:
1569:
1549:
1502:
1495:
1474:
1417:
1402:
1376:
1361:
1355:. p. 58.
1343:. Foreword by
1321:
1314:
1289:
1259:
1229:
1198:
1197:
1195:
1192:
1191:
1190:
1185:
1184:
1183:
1177:
1171:
1165:
1157:
1152:
1147:
1142:
1137:
1124:
1119:
1114:
1108:
1101:
1098:
1078:Main article:
1075:
1072:
1035:
1032:
1031:
1030:
1021:typically use
1016:
997:
975:
972:
970:
967:
942:
939:
923:
864:Ernest Marsden
846:to infer that
844:radium bromide
825:electric spark
764:
761:
745:bladder cancer
707:Main article:
704:
701:
650:alpha spectrum
641:
638:
629:
626:
613:
610:
593:
590:
558:
555:
539:potential well
502:
499:
445:, and that of
384:Main article:
381:
378:
376:
373:
352:
332:
316:
313:
273:speed of light
261:kinetic energy
245:
225:
214:Greek alphabet
181:, also called
174:
173:
165:
159:
158:
150:
144:
143:
87:
81:
80:
77:
73:
72:
67:
61:
60:
57:
51:
50:
45:
33:Alpha particle
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
2891:
2880:
2877:
2875:
2874:Radioactivity
2872:
2870:
2867:
2865:
2862:
2861:
2859:
2845:
2841:
2837:
2836:Radioactivity
2833:
2826:
2820:
2817:
2815:
2812:
2810:
2807:
2805:
2802:
2800:
2797:
2796:
2794:
2790:
2784:
2781:
2779:
2776:
2774:
2771:
2769:
2766:
2764:
2761:
2760:
2758:
2754:
2748:
2745:
2743:
2740:
2738:
2735:
2733:
2730:
2728:
2725:
2723:
2720:
2718:
2715:
2713:
2710:
2708:
2705:
2703:
2700:
2698:
2695:
2693:
2690:
2688:
2685:
2683:
2680:
2678:
2675:
2673:
2670:
2668:
2665:
2661:
2658:
2656:
2653:
2652:
2650:
2649:
2647:
2641:
2631:
2628:
2626:
2623:
2621:
2618:
2616:
2613:
2611:
2608:
2606:
2603:
2601:
2598:
2596:
2593:
2591:
2588:
2586:
2583:
2581:
2578:
2576:
2573:
2571:
2568:
2566:
2563:
2562:
2559:
2553:
2550:
2548:
2545:
2543:
2540:
2538:
2535:
2533:
2530:
2528:
2525:
2523:
2520:
2518:
2515:
2513:
2510:
2508:
2505:
2503:
2502:Beta particle
2500:
2498:
2495:
2493:
2490:
2488:
2487:Cluster decay
2485:
2483:
2480:
2479:
2477:
2475:
2471:
2465:
2462:
2460:
2457:
2455:
2452:
2450:
2447:
2445:
2442:
2440:
2437:
2435:
2432:
2430:
2427:
2426:
2424:
2422:
2418:
2415:
2413:Main articles
2411:
2406:
2399:
2394:
2392:
2387:
2385:
2380:
2379:
2376:
2372:
2370:
2365:
2357:
2351:
2345:
2341:
2340:W. H. Freeman
2337:
2332:
2331:
2327:
2318:
2314:
2310:
2306:
2302:
2298:
2294:
2290:
2289:
2281:
2278:
2273:
2269:
2264:
2259:
2255:
2251:
2246:
2241:
2237:
2233:
2229:
2221:
2218:
2213:
2209:
2205:
2201:
2197:
2193:
2189:
2185:
2181:
2177:
2173:
2166:
2163:
2158:
2154:
2149:
2144:
2140:
2136:
2132:
2125:
2122:
2116:
2113:
2101:
2095:
2092:
2086:
2083:
2070:
2066:
2062:
2056:
2054:
2050:
2037:
2033:
2027:
2024:
2019:
2015:
2011:
2007:
2002:
1997:
1993:
1989:
1988:
1979:
1975:
1971:
1967:
1963:
1959:
1955:
1951:
1946:
1941:
1937:
1933:
1932:
1927:
1923:
1916:
1913:
1907:
1904:
1899:
1895:
1891:
1887:
1883:
1879:
1875:
1868:
1865:
1860:
1854:
1850:
1846:
1839:
1836:
1824:
1820:
1813:
1810:
1805:
1801:
1797:
1793:
1789:
1785:
1781:
1777:
1773:
1769:
1768:
1760:
1757:
1752:
1748:
1743:
1738:
1734:
1730:
1726:
1722:
1718:
1711:
1708:
1703:
1699:
1695:
1691:
1687:
1683:
1679:
1675:
1671:
1667:
1660:
1657:
1652:
1648:
1644:
1640:
1637:(1): 245–65.
1636:
1632:
1625:
1622:
1618:
1614:
1610:
1606:
1602:
1598:
1594:
1588:
1585:
1580:
1576:
1572:
1570:0-471-35633-6
1566:
1562:
1561:
1553:
1550:
1545:
1541:
1537:
1533:
1529:
1525:
1521:
1517:
1513:
1506:
1503:
1498:
1492:
1488:
1481:
1479:
1475:
1470:
1466:
1462:
1458:
1453:
1448:
1444:
1440:
1436:
1432:
1428:
1421:
1418:
1413:
1406:
1403:
1399:
1396:
1392:
1389:
1383:
1381:
1377:
1372:
1368:
1364:
1358:
1354:
1350:
1346:
1342:
1341:
1336:
1335:Chrisp, Peter
1332:
1325:
1322:
1317:
1311:
1307:
1303:
1296:
1294:
1290:
1277:
1273:
1269:
1263:
1260:
1247:
1243:
1239:
1233:
1230:
1217:
1213:
1209:
1203:
1200:
1193:
1189:
1186:
1182:
1178:
1176:
1172:
1170:
1166:
1164:
1163:β (beta) rays
1161:
1160:
1158:
1156:
1153:
1151:
1148:
1146:
1143:
1141:
1138:
1136:
1132:
1128:
1125:
1123:
1120:
1118:
1117:Beta particle
1115:
1112:
1111:Alpha process
1109:
1107:
1106:Alpha nuclide
1104:
1103:
1099:
1097:
1095:
1091:
1087:
1081:
1073:
1071:
1067:
1065:
1060:
1057:
1052:
1048:
1044:
1041:
1040:radionuclides
1033:
1028:
1024:
1020:
1017:
1014:
1010:
1009:Plutonium-238
1006:
1002:
998:
994:
990:
986:
985:americium-241
982:
978:
977:
973:
968:
966:
964:
961:detected the
960:
956:
952:
948:
940:
938:
935:
933:
927:
922:
920:
916:
912:
903:
896:
893:Energy-loss (
891:
887:
885:
879:
875:
873:
869:
865:
861:
857:
853:
849:
848:J. J. Thomson
845:
841:
837:
833:
828:
826:
822:
818:
812:
810:
806:
797:
789:
782:
778:
774:
769:
762:
760:
758:
754:
750:
746:
742:
738:
734:
729:
725:
721:
717:
710:
702:
700:
698:
694:
688:
686:
682:
676:
674:
670:
665:
663:
659:
651:
646:
639:
637:
635:
627:
625:
623:
622:alpha process
619:
611:
609:
607:
603:
599:
591:
589:
587:
583:
580:
576:
572:
568:
564:
556:
554:
552:
551:nuclear force
548:
545:However, the
543:
540:
536:
532:
531:nuclear force
528:
524:
520:
519:nuclear force
516:
512:
508:
500:
498:
496:
492:
488:
487:tellurium-104
484:
479:
475:
471:
467:
463:
459:
454:
452:
448:
444:
440:
436:
432:
431:atomic number
428:
424:
420:
416:
408:
407:cloud chamber
403:
397:
396:cloud chamber
392:
387:
379:
374:
372:
370:
366:
350:
330:
322:
314:
312:
309:
305:
301:
296:
294:
290:
286:
282:
278:
274:
270:
266:
262:
258:
253:
239:
235:
219:
215:
211:
207:
204:
200:
196:
192:
188:
184:
180:
172:
171:
166:
164:
160:
157:
156:
151:
149:
145:
141:
140:
88:
86:
82:
78:
74:
71:
68:
66:
62:
58:
56:
52:
48:
41:
36:
30:
19:
2840:Radiobiology
2722:Radiobiology
2682:Laser safety
2496:
2361:
2335:
2292:
2286:
2280:
2238:(23): 4314.
2235:
2231:
2220:
2179:
2175:
2165:
2138:
2134:
2124:
2115:
2103:. Retrieved
2094:
2085:
2073:. Retrieved
2064:
2040:. Retrieved
2026:
1991:
1985:
1935:
1929:
1921:
1915:
1906:
1881:
1877:
1867:
1844:
1838:
1828:15 September
1826:. Retrieved
1822:
1812:
1771:
1765:
1759:
1724:
1721:Epidemiology
1720:
1710:
1672:(2): 293–9.
1669:
1665:
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1634:
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1612:
1608:
1604:
1600:
1587:
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1519:
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1430:
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1411:
1405:
1397:
1390:
1339:
1324:
1301:
1280:. Retrieved
1271:
1262:
1250:. Retrieved
1241:
1232:
1220:. Retrieved
1211:
1202:
1133:rather than
1083:
1068:
1061:
1045:
1037:
1027:static cling
1023:polonium-210
1005:space probes
969:Applications
944:
936:
929:
924:N + α → O +
908:
880:
876:
872:plum pudding
868:zinc sulfide
829:
821:Thomas Royds
813:
809:Paul Villard
802:
733:polonium-210
712:
689:
677:
666:
655:
631:
615:
604:, and other
602:synchrotrons
595:
592:Accelerators
560:
544:
504:
455:
412:
368:
318:
297:
291:, or by the
254:
186:
182:
178:
177:
169:
154:
138:
118:(62) Da
29:
2464:Ultraviolet
2459:Radio waves
2105:30 December
2075:30 December
2042:15 November
1984:"Erratum".
1982:. See also
1619:for fusion.
1340:Big History
1122:Cosmic rays
1090:soft errors
895:Bragg curve
860:Hans Geiger
747:related to
741:lung cancer
693:micrometres
681:β particles
658:alpha decay
634:cosmic rays
628:Cosmic rays
575:fissionable
565:process of
483:beryllium-8
478:transuranic
458:radioactive
423:mass number
415:alpha decay
386:Alpha decay
380:Alpha decay
365:Hans Geiger
308:cosmic rays
283:, with low
210:alpha decay
55:Composition
47:Alpha decay
2858:Categories
2645:and health
2643:Radiation
2512:Cosmic ray
2295:(1): 2–9.
1858:0671621300
1278:. May 2024
1248:. May 2024
1218:. May 2024
1194:References
1047:Radium-223
963:antimatter
949:using the
884:Bohr model
728:chromosome
716:Thorotrast
598:cyclotrons
507:beta decay
183:alpha rays
101:10 kg
65:Statistics
18:Alpha rays
2799:Half-life
2672:Dosimetry
2507:Gamma ray
2454:Microwave
2444:Starlight
2405:Radiation
2254:1420-3049
2232:Molecules
2001:1103.3312
1978:118484566
1945:1103.3312
1898:1941-5982
1544:0077-8923
1461:0950-1207
1371:940282526
1175:Delta ray
1169:Gamma ray
1003:used for
777:electrons
759:in 2006.
582:actinides
491:gamma ray
351:β
331:α
238:electrons
2449:Sunlight
2434:Infrared
2317:43748644
2272:31779154
2204:17671351
2157:23863050
2069:Archived
1970:21516103
1804:23455633
1796:14078362
1751:28520643
1651:24275177
1579:43118182
1349:New York
1135:helium-4
1131:helium-3
1100:See also
1088:(DRAM) "
773:helium-4
755:officer
691:40
685:neutrons
470:actinium
427:nucleons
279:form of
277:ionizing
269:velocity
203:helium-4
199:particle
195:neutrons
193:and two
152:+2
79:α, α, He
2660:chronic
2297:Bibcode
2263:6930656
2212:1585204
2184:Bibcode
2036:PhysOrg
2018:4359058
1950:Bibcode
1776:Bibcode
1767:Science
1742:5540354
1702:4023181
1694:3576584
1674:Bibcode
1524:Bibcode
1439:Bibcode
1051:calcium
993:current
974:Devices
953:at the
919:protons
579:fissile
466:thorium
462:uranium
443:thorium
439:uranium
375:Sources
206:nucleus
191:protons
167:0
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104:
70:Bosonic
2864:Helium
2842:, and
2346:
2315:
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2252:
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1987:Nature
1976:
1968:
1931:Nature
1922:et al.
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1282:18 May
1252:18 May
1222:18 May
1159:Rays:
1127:Helion
989:ionize
832:energy
699:deep.
509:, the
495:energy
474:radium
472:, and
447:radium
267:and a
134:
76:Symbol
2655:acute
2552:X-ray
2439:Light
2313:S2CID
2208:S2CID
2014:S2CID
1996:arXiv
1974:S2CID
1940:arXiv
1800:S2CID
1690:JSTOR
1597:light
1469:92981
1465:JSTOR
1094:Intel
979:Some
697:cells
533:. In
451:radon
125:3.727
108:4.001
90:6.644
2344:ISBN
2268:PMID
2250:ISSN
2200:PMID
2153:PMID
2107:2023
2077:2023
2044:2011
1966:PMID
1894:ISSN
1853:ISBN
1830:2011
1792:PMID
1747:PMID
1698:PMID
1647:PMID
1575:OCLC
1565:ISBN
1540:ISSN
1491:ISBN
1457:ISSN
1367:OCLC
1357:ISBN
1310:ISBN
1284:2024
1276:NIST
1254:2024
1246:NIST
1224:2024
1216:NIST
1013:lead
862:and
819:and
781:Lead
743:and
620:and
577:and
517:and
485:and
419:atom
315:Name
293:skin
163:Spin
137:GeV/
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97:(21)
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85:Mass
2305:doi
2258:PMC
2240:doi
2192:doi
2143:doi
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2006:doi
1992:475
1958:doi
1936:473
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