Table 1 Energy spectra of a Ra-223 vial with MEGP and HEGP
Energy peak | Relative detector sensitivity with HEGP to MEGP collimator | Relative peak height to that at 84 keV with HEGP | % decrease in sensitivity by attenuation medium | |||
|---|---|---|---|---|---|---|
Attenuation medium (−) | Attenuation medium (+)a | Attenuation medium (−) | Attenuation medium (+)a | MEGP | HEGP | |
84 | 99.5 | 98.3 | NA | NA | 2.9 | 2.3 |
154 | 70.2 | 74.1 | 29.3 | 31.2 | 3.4 | 1.1 |
269 | 69.8 | 69.9 | 18.9 | 18.8 | 4.3 | 4.1 |
351 | 52.0 | 56.8 | 11.2 | 12.0 | 5.5 | 0.9 |
402 | 47.5 | 46.4 | 8.8 | 8.8 | 2.4 | 4.1 |