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Chapter 16: Selected Radioactive Isotopes

Last updated

Mar 12, 2024
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- Chapter 15: Atomic Masses
- Chapter 17: Useful Information

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Decay modes are , , , electron capture (EC) and isomeric transition (IT). EC results in the same daughter nucleus as would decay. IT is a transition from a metastable excited state. Energies for decays are the maxima; average energies are roughly one-half the maxima.

Table : Selected Radioactive Isotopes
t _1/2	DecayMode(s)	Energy(MeV)	Percent	-Ray Energy(MeV)	Percent
12.33 y		0.0186	100%
5730 y		0.156	100%
9.96 min		1.20	100%
2.602 y		0.55	90%	1.27	100%
14.28 d		1.71	100%
87.4 d		0.167	100%
		0.710	100%
		1.31	89%
22.3 h		0.827	87%	0.373	87%
				0.618	87%
165 d		0.257	100%
27.70 d	EC			0.320	10%
5.59d		3.69	28%	1.33	28%
				1.43	28%
8.27 h		1.80	43%	0.169	43%
				0.378	43%
44.6 d		0.273	45%	1.10	57%
		0.466	55%	1.29	43%
5.271 y		0.318	100%	1.17	100%
				1.33	100%
244.1 d	EC			1.12	51%
78.3 h	EC			0.0933	70%
				0.185	35%
				0.300	19%
				others
118.5 d	EC			0.121	20%
				0.136	65%
				0.265	68%
				0.280	20%
				others
18.8 d		0.69	9%	1.08	9%
		1.77	91%
64.8 d	EC			0.514	100%
28.8 y		0.546	100%
64.1 h		2.28	100%
6.02 h	IT			0.142	100%
99.5 min	IT			0.392	100%
13.0 h	EC			0.159
8.040 d		0.248	7%	0.364	85%
		0.607	93%	others
		others
32.3 h	EC			0.0400	35%
				0.372	32%
				0.411	25%
				others
30.17 y		0.511	95%	0.662	95%
		1.17	5%
12.79 d		1.035		0.030	25%
				0.044	65%
				0.537	24%
				others
2.696 d		1.161		0.412
64.1 h	EC			0.0733	100%
138.38 d		5.41	100%
		4.68	5%	0.186	100%
		4.87	95%
		4.68		numerous	<0.400%
		4.22	23%	0.050	23%
		4.27	77%
		numerous		numerous	<0.250%
		4.96 (max.)
		5.19	11%		73%
		5.23	15%	0.013	15%
		5.24	73%	0.052	10%
				others
		Max. 5.44		0.075
		5.37	88%	others
		5.32	11%
		others

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