This spectrum was sent to me by Peter Bossew of the University of Salzburg. It is a collation of a large number of spectra measured over a number of years. This particular spectrum represents a count period of 15,240,200 seconds live time (176 days). Peter has also reported the analysis of a collated spectrum representing 3.3 years-worth of counting over 16 years of operation. (Applied Radiation and Isotopes 62 (2005) 635–644) The analyses presented illustrate some of the more esoteric effects explained in Chapter 13, where detector background is discussed. The decay schemes of 214Bi and 228Ac, in particular are very complex and there is always potential for coincidence summing. Some minor peaks for which identification is, at best, tentative could be sum peaks.

	Measured Energy (keV)	True Energy (keV)	Peak Counts	Nuclide	Emission Probability (%)	Source of radiation
1	205.36	205.31	3805	235U	5.01	Primordial
		205.68		214Pb	0.0114	238U series (226Ra)
		205.99		228Th	0.0185	232Th series
2	209.37	209.26	3327	228Ac	3.89	232Th series
		210.62		227Th	1.22	235U series
3	215.91	214.85	1174	228Ac	0.029	232Th series
		215.99		228Th	0.226	232Th series
		216.47		214Pb	0.01	238U series (226Ra)
4	235.96	235.96	0	227Th	12.6	235U series
5	238.63	238.63	47778	212Pb	43.6	232Th series
6	240.76	240.99	819	220Ra	4.12	235U series
		240.99		224Ra	4.12	232Th series
7	242	242	21987	214Pb	7.268	238U series (226Ra)
8	256.23	256.23	218	227Th	6.8	235U series
		257.52		228Ac	0.03	232Th series
9	257.97	258.19	2427	234mPa	0.0754	238U series
		258.87		214Pb	0.5318	238U series (226Ra)
10	269.46	268.8	432	214Bi	0.0161	238U series (226Ra)
		269.46		223Ra	13.7	235U series
		270.24		228Ac	3.46	232Th series
11	270.27	271.23	3427	219Ra	10.8	235U series
12	287.98	288.08	870	212Bi	0.32	232Th series
13	295.22	295.22	43578	214Pb	18.5	238U series (226Ra)
14	300.09	299.98	2985	227Th	2.16	235U series
		300.09		212Pb	3.18	232Th series
15	327.92	327.44	1767	b+/b-Ann.	0.12	232Th series
		327.94		212Bi	0.121	232Th series
		328		228Ac	2.95	232Th series
16	338.35	338.28	7426	223Ra	2.79	235U series
		338.32		228Ac	11.27	232Th series
17	351.87	351.93	67397	214Pb	35.6	238U series (226Ra)
18	386.95	386.77	570	214Bi	0.296	238U series (226Ra)
19	388.72	388.88	806	214Bi	0.393	238U series (226Ra)
		389.36		228Ac	0.0103	232Th series
20	463	462	3022	214Pb	0.213	238U series (226Ra)
		463		228Ac	4.4	232Th series
21	510.79	510.7	182839	208Tl	22.6	232Th series
22	569.85	569.7	2992	207mPb	97.87	207Pb(n,n')
		570.82		228Ac	0.182	232Th series
23	583.02	583.19	14229	208Tl	85	232Th series
		583.41		228Ac	0.111	232Th series
24	609.14	609.31	52510	214Bi	45.49	238U series (226Ra)
25	662.95	661.66	2860	137Cs	84.99	fission
		663.82		228Ac	0.028	232Th series
26	675.56	674.76	565	228Ac	0.109	232Th series
27	693.02	692.5	2654	228Ac	0.0056	232Th series
		693.3		214Bi	0.0059	238U series (226Ra)

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