Ratio of Photon Dose to β-Dose
| Collection thickness (cm) | 131I | 153Sm | 177Lu | 18F | 68Ga | 124I |
| 0.5 | 4.5% | 1.3% | 0.7% | 10.5% | 1.5% | 7.2% |
| 1 | 7.5% | 2.0% | 1.1% | 17.4% | 2.5% | 11.9% |
| 1.5 | 9.8%* | 2.6% | 1.5% | 22.9%* | 3.3% | 15.6% |
* Results verified by Monte Carlo simulation.
For β− emitters, collections are assumed to have radius 1/μ, where μ is mass attenuation coefficient for dominant photon energy. For positron emitters, collections are assumed to have radius of 10 cm.