Bebig/Theragenics 125.SO6

Bebig/Theragenics 125.SO6 Dosimetry Datasets

Note: The following tables are adapted from Rivard et al., Med. Phys. 31, 633-674 (2004).

Table I. NIST standard WAFAC calibration dates for air kerma strength for each manufacturer, and dose rate constant values. Note that for a given source type, the % change in Λ from the 1999 value is different for different seed models.

Manufacturer	Source Type	NIST date used by ADCL and NIST as standard	consensusΛ [cGy -h·^-1·U^-1]	% difference in Λ from 1999 value
Bebig/Theragenics 125.SO6	¹²⁵I	January 27, 2001	1.012	+2.2%

Table II.Consensus g(r) values

r[cm]	0.10	0.15	0.25	0.50	0.75	1.00	1.50	2.00
Line source approximation L=3.5 mm	1.010	1.022	1.030	1.030	1.020	1.000	0.937	0.857
Point source approximation		0.760	0.908	1.001	1.012	1.000	0.942	0.863

r[cm]	3.00	4.00	5.00	6.00	7.00	8.00	9.00	10.00
Line source approximation L=3.5 mm	0.689	0.538	0.409	0.313	0.232	0.176	0.134	0.0957
Point source approximation	0.695	0.543	0.413	0.316	0.234	0.178	0.135	0.0967

Interpolated data are boldface, and italicized data are non-consensus data obtained from candidate datasets.

Table III. F(r,θ)

Polar angleθ (degrees)

		0	5	10	20	30	40	50	60	70	80	Φ_an(r)
r [cm]	0.25	0.302	0.352	0.440	0.746	0.886	0.943	0.969	0.984	0.994	0.998	1.122
	0.5	0.429	0.436	0.476	0.686	0.820	0.897	0.946	0.974	0.989	0.998	0.968
	1	0.512	0.509	0.557	0.721	0.828	0.898	0.942	0.970	0.988	0.998	0.939
	2	0.579	0.576	0.622	0.757	0.846	0.907	0.947	0.974	0.990	1.000	0.939
	3	0.610	0.610	0.651	0.771	0.857	0.908	0.944	0.967	0.984	0.994	0.938
	4	0.631	0.635	0.672	0.785	0.862	0.913	0.947	0.966	0.985	1.0000	0.940
	5	0.649	0.651	0.689	0.790	0.867	0.918	0.949	0.967	0.987	0.993	0.941
	7	0.684	0.689	0.721	0.807	0.874	0.912	0.946	0.976	0.994	0.999	0.949

Italicized data are non-consensus data obtained from candidate datasets.

Table IV. Dose rates (cGy · h-1 · U-1) as a function of distance for Bebig/Theragenics 125.SO6 brachytherapy sources using the 1-D dosimetry formalism of Eq. (11) with interpolation for gL(r) and fan(r).

r (cm)	0.5	1.0	1.5	2.0	3.0	4.0	5.0	6.0	7.0
	3.922	0.950	0.398	0.205	0.0733	0.0323	0.0157	0.00840	0.00459