TABLE V.
Open field off-axis ratios for 6-MV x-rays. Sample data from a Varian Clinac 2100C accelerator.
| OADa | ||||||||
|---|---|---|---|---|---|---|---|---|
| (cm) | 0 | 2 | 4 | 6 | 8 | 10 | 15 | 18 |
| Depth (cm) 1.5 | 1.000 | 1.006 | 1.022 | 1.030 | 1.034 | 1.043 | 1.055 | 1.058 |
| 3.0 | 1.000 | 1.011 | 1.027 | 1.033 | 1.040 | 1.045 | 1.056 | 1.058 |
| 5 | 1.000 | 1.017 | 1.033 | 1.041 | 1.046 | 1.048 | 1.058 | 1.057 |
| 8 | 1.000 | 1.011 | 1.030 | 1.036 | 1.040 | 1.043 | 1.050 | 1.051 |
| 10 | 1.000 | 1.006 | 1.028 | 1.030 | 1.031 | 1.031 | 1.033 | 1.032 |
| 12 | 1.000 | 1.006 | 1.023 | 1.028 | 1.029 | 1.026 | 1.026 | 1.026 |
| 15 | 1.000 | 1.007 | 1.016 | 1.025 | 1.025 | 1.018 | 1.016 | 1.016 |
a
Radial off axis distances projected on a plane at 100 cm from source.