Figure 1
Figure 2
Figure 3
Neutron dose equivalents in μSv per Gy photon dose in isocenter for all measuring positions and gantry angles 0° and 270°
| Gantry 0° | Gantry 270° | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| A | B | C | D | E | A | B | C | D | E | ||
| (μSv/Gy) | (μSv/Gy) | (μSv/Gy) | (μSv/Gy) | (μSv/Gy) | (μSv/Gy) | (μSv/Gy) | (μSv/Gy) | (μSv/Gy) | (μSv/Gy) | ||
| Poje | LR 115 | 0.04 | 0.08 | 10 | 0.04 | 0.1 | 0.17 | 20 | 0.13 | ||
| et al.5 | Active detector | 0.052 | 0.1 | 14.3 | 0.052 | ||||||
| Our | 0.008 | 0.0006 | 8.2 | 1.3∙10-12 | 3297 | 0.01 | 0.004 | 10.3 | 4.21∙10-11 | 3333 | |
| results | CR-39 | (0.0006) | (0.00004) | (0.6) | (7∙10-14) | (264) | (0.008) | (0.0002) | (0.5) | (2∙10-12) | (202) |
Total MC calculated neutron fluence in measuring positions A, B, C, D and E for gantry angles 0° and 270°_ Neutron fluence is in number of neutrons per cm2 per electron impinging on target_ Results are normalized to source particle
| Measuring position | |||||
|---|---|---|---|---|---|
| Gantry angle | A | B | C | D | E |
| 0° | 5.6 ∙ 10-13 | 5.3 ∙ 10-14 | 3.6 ∙ 10-10 | 8.4 ∙ 10-24 | 1.5 ∙ 10-8 |
| 270° | 6.6 ∙ 10-13 | 3.4 ∙ 10-14 | 4.2 ∙ 10-10 | 1.6 ∙ 10-22 | 1.5 ∙ 10-8 |
Calibration coefficients for neutron detector CR-39 for measuring positions C and E for gantry angles 0° and 270°
| Position | G 0° | G 270° |
|---|---|---|
| μSv/(track/mm2) | μSv/(track/mm2) | |
| C | 6,52 | 11,20 |
| E | 151,61 | 194,97 |