Radioactive Decay Series
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Note 1 Isotopes of elements are normally identified using this notation element symbols with atomic mass directly above atomic number This example considers the isotope of Hydrogen, H is the chemical symbol for Hydrogen, 1 is the atomic number (number of protons) and 2 is the atomic mass (protons + neutrons). Unfortunately, the limitations of some web browsers make it impracticable for me to follow the normal notation within this page. For this reason I will be using the ammended notation of 21H
Note 2 These series are the ones regularly quoted in text books, however, there are many other short series (often only involving a single decay before becoming stable,) there could be additional long series and it is possible to extend these series to encompass many of the synthetic elements generated artificially.
Thorium Series
ElementDecayHalf Life
25298CfAlpha 42α2.6 years
24896CmAlpha 42α3.4 x105 years
24494PuAlpha 42α 8.0 x107 years
24092UBeta  0-1β 14.1 hours
24093NpBeta  0-1β 1.0 Hours
24094PuAlpha 42α 6.5 x103 years
23692UAlpha 42α 2.3 x107 years
23290ThAlpha 42α1.4 x1010 Years
22888RaBeta  0-1β6.7 Years
22889AcBeta  0-1β6.1 Hours
22890ThAlpha 42α1.9 Years
22488RaAlpha 42α3.6 Days
22086RnAlpha 42α55 Seconds
21684PoAlpha 42α3.0 x10-7 Seconds
22282PbBeta  0-1β10.6 Hours
21283BiAlpha 42α
Beta  0-1β
3.0 x10-7 Seconds
If decay of 21283Bi is α
20881TlBeta  0-1β3.1 Minutes
20882Pb Stable
If decay of 21283Bi is β
21284PoAlpha 42α25 Seconds
20882Pb Stable
Uranium Series (Radium Series)
ElementDecayHalf Life
23892UAlpha 42α4.5 x109 Years
23490ThBeta  0-1β2.4 Days
23491PaBeta  0-1β6.7 Hours
23492UAlpha 42α2.4 x105 Years
23090ThAlpha 42α8 x104 Years
22688RaAlpha 42α1.6 x103 Years
22286RnAlpha 42α3.8 Days
21884PoAlpha 42α3.1 Minutes
21482PbBeta  0-1β27 Minutes
21483BiAlpha 42α
Beta  0-1β
20 Minutes
If decay of 21483Bi is α
21081TlBeta  0-1β1.8 Minutes
21082PbBeta  0-1β20 Years
21083BiAlpha 42α5 Days
20681TlBeta  0-1β24.2 Minutes
20682Pb Stable
If decay of 21483Bi is β
21484PoAlpha 42α1.6 x10-4 Seconds
21082PbBeta  0-1β20 Years
21083BiAlpha 42α5 Days
20681TlBeta  0-1β24.2 Minutes
20682Pb Stable
Actinium Series
ElementDecayHalf Life
23994PuAlpha 42α2.4 x104 Years
23592UAlpha 42α7.1 x108 Years
23190ThBeta  0-1β26 Hours
23191PaAlpha 42α3.2 x104 Years
22789AcBeta  0-1β22 Years
22790ThAlpha 42α18 Days
22388RaAlpha 42α11 Days
21986ThAlpha 42α4 Seconds
22584PoAlpha 42α1.8 x10-3 Seconds
21182PbBeta  0-1β36 Minutes
21183BiAlpha 42α2.2 Minutes
20781TlBeta  0-1β4.8 Minutes
20782Pb Stable
Neptunium Series
ElementDecayHalf Life
24998CfAlpha 42α351 years
24596CmAlpha 42α8.5 x103 years
24194PuBeta  0-1β14.4 years
24195AmAlpha 42α432 years
23793NpAlpha 42α2.1x 106 years
23391PaBeta  0-1β27 days
23392U Alpha 42α1.6x 105 years
22990ThAlpha 42α7.3 x103 years
22588RaBeta  0-1β14.9 days
22589AcAlpha 42α10 days
22187FrAlpha 42α4.8 minutes
21785AtAlpha 42α32x 10-3 seconds
21383BiAlpha 42α
Beta  0-1β
46.5 minutes
If decay of 21383Bi is α
20981TlBeta  0-1β2.2 min
20982PbBeta  0-1β3.2 hours
20983BiAlpha 42α1.9x 1019 years
20581Tl stable
If decay of 21383Bi is β
21384PoAlpha 42α3.7x 10-6 seconds
20982PbBeta  0-1β2.2 min
20983BiAlpha 42α1.9x 1019 years
20581Tl stable