Table 2.
The reflection coefficient of photons for various Pb thickness layers layered over ordinary concrete as a function of reflected angles calculated using the FLUKA code (wall-reflection coefficient).
| Energy (MeV) | Angle of reflection or scatter (degrees) from surface of concrete | |||||
|---|---|---|---|---|---|---|
| 92 | 105 | 120 | 135 | 150 | 165 | |
| 0.2 mm Pb | ||||||
| 0.25 | 0.47 | 4.37 | 10.02 | 14.79 | 18.14 | 19.67 |
| 0.662 | 0.28 | 3.99 | 7.87 | 10.61 | 12.30 | 12.96 |
| 1.25 | 0.20 | 2.74 | 5.15 | 6.83 | 7.87 | 8.21 |
| 3 | 0.15 | 1.85 | 3.52 | 4.78 | 5.55 | 5.79 |
| 5 | 0.13 | 1.65 | 3.25 | 4.47 | 5.21 | 5.43 |
| 7 | 0.11 | 1.54 | 3.05 | 4.15 | 4.83 | 5.05 |
| 10 | 0.09 | 1.38 | 2.79 | 3.77 | 4.39 | 4.59 |
| 15 | 0.07 | 1.19 | 2.45 | 3.36 | 3.86 | 4.05 |
| 20 | 0.06 | 1.02 | 2.13 | 2.93 | 3.43 | 3.61 |
| 0.5 mm Pb | ||||||
| 0.25 | 0.33 | 2.40 | 5.38 | 8.32 | 10.47 | 11.42 |
| 0.662 | 0.20 | 2.42 | 5.27 | 7.40 | 8.80 | 9.33 |
| 1.25 | 0.15 | 2.00 | 3.99 | 5.46 | 6.37 | 6.74 |
| 3 | 0.16 | 1.87 | 3.73 | 5.35 | 6.40 | 6.78 |
| 5 | 0.15 | 1.94 | 4.12 | 6.13 | 7.48 | 7.94 |
| 7 | 0.14 | 1.88 | 4.08 | 6.05 | 7.40 | 7.82 |
| 10 | 0.12 | 1.70 | 3.71 | 5.47 | 6.58 | 6.95 |
| 15 | 0.09 | 1.44 | 3.13 | 4.51 | 5.41 | 5.61 |
| 20 | 0.07 | 1.22 | 2.64 | 3.75 | 4.46 | 4.70 |
| 1 mm Pb | ||||||
| 0.25 | 0.29 | 2.02 | 4.07 | 6.02 | 7.44 | 8.04 |
| 0.5 | 0.16 | 1.38 | 3.17 | 4.77 | 5.88 | 6.34 |
| 0.662 | 0.16 | 1.47 | 3.31 | 4.79 | 5.78 | 6.07 |
| 1 | 0.08 | 0.89 | 1.89 | 2.65 | 3.16 | 3.31 |
| 1.25 | 0.13 | 1.42 | 2.95 | 4.10 | 4.86 | 5.09 |
| 2 | 0.15 | 1.58 | 3.10 | 4.34 | 5.14 | 5.37 |
| 3 | 0.17 | 1.79 | 3.59 | 5.15 | 6.24 | 6.63 |
| 5 | 0.19 | 2.18 | 4.61 | 6.98 | 8.63 | 9.24 |
| 7 | 0.19 | 2.34 | 5.15 | 7.92 | 9.98 | 10.69 |
| 10 | 0.18 | 2.30 | 5.13 | 7.99 | 10.02 | 10.65 |
| 15 | 0.14 | 1.96 | 4.43 | 6.75 | 8.42 | 8.98 |
| 20 | 0.11 | 1.65 | 3.69 | 5.53 | 6.82 | 7.20 |
| 2 mm Pb | ||||||
| 0.25 | 0.29 | 1.99 | 3.89 | 5.69 | 6.92 | 7.40 |
| 0.5 | 0.14 | 1.07 | 2.14 | 3.14 | 3.86 | 4.08 |
| 0.662 | 0.13 | 1.05 | 2.12 | 3.07 | 3.70 | 3.91 |
| 1 | 0.07 | 0.62 | 1.27 | 1.81 | 2.16 | 2.25 |
| 1.25 | 0.11 | 1.04 | 2.11 | 2.97 | 3.55 | 3.65 |
| 2 | 0.14 | 1.41 | 2.71 | 3.79 | 4.49 | 4.70 |
| 3 | 0.17 | 1.82 | 3.52 | 4.97 | 6.02 | 6.33 |
| 5 | 0.20 | 2.39 | 4.87 | 7.23 | 8.94 | 9.51 |
| 7 | 0.22 | 2.76 | 5.77 | 8.77 | 11.01 | 11.65 |
| 10 | 0.24 | 3.01 | 6.40 | 9.83 | 12.37 | 13.46 |
| 15 | 0.22 | 2.88 | 6.19 | 9.57 | 12.12 | 13.19 |
| 20 | 0.18 | 2.49 | 5.36 | 8.24 | 10.40 | 11.25 |
| 3 mm Pb | ||||||
| 0.25 | 0.29 | 1.98 | 3.90 | 5.66 | 6.91 | 7.42 |
| 0.5 | 0.14 | 1.05 | 1.99 | 2.87 | 3.50 | 3.68 |
| 0.662 | 0.13 | 1.00 | 1.86 | 2.65 | 3.19 | 3.35 |
| 1 | 0.07 | 0.57 | 1.08 | 1.52 | 1.82 | 1.89 |
| 1.25 | 0.11 | 0.95 | 1.81 | 2.59 | 3.06 | 3.20 |
| 2 | 0.14 | 1.39 | 2.60 | 3.63 | 4.31 | 4.52 |
| 3 | 0.17 | 1.86 | 3.57 | 5.05 | 6.07 | 6.42 |
| 5 | 0.21 | 2.55 | 5.11 | 7.48 | 9.18 | 9.75 |
| 7 | 0.23 | 3.04 | 6.13 | 9.18 | 11.36 | 12.12 |
| 10 | 0.26 | 3.42 | 6.97 | 10.47 | 13.19 | 14.05 |
| 15 | 0.26 | 3.52 | 7.09 | 10.71 | 13.48 | 14.52 |
| 20 | 0.22 | 3.18 | 6.44 | 9.68 | 12.13 | 13.17 |
| 4 mm Pb | ||||||
| 0.25 | 0.29 | 1.99 | 3.90 | 5.66 | 6.90 | 7.42 |
| 0.5 | 0.14 | 1.04 | 1.96 | 2.81 | 3.41 | 3.63 |
| 0.662 | 0.13 | 0.97 | 1.80 | 2.55 | 3.05 | 3.20 |
| 1 | 0.07 | 0.55 | 1.02 | 1.44 | 1.70 | 1.77 |
| 1.25 | 0.11 | 0.91 | 1.72 | 2.41 | 2.91 | 2.99 |
| 2 | 0.14 | 1.39 | 2.58 | 3.61 | 4.29 | 4.48 |
| 3 | 0.17 | 1.91 | 3.64 | 5.16 | 6.19 | 6.55 |
| 5 | 0.21 | 2.67 | 5.32 | 7.73 | 9.50 | 10.09 |
| 7 | 0.24 | 3.23 | 6.46 | 9.51 | 11.82 | 12.56 |
| 10 | 0.27 | 3.72 | 7.40 | 11.04 | 13.67 | 14.66 |
| 15 | 0.27 | 3.98 | 7.78 | 11.42 | 14.24 | 15.40 |
| 20 | 0.24 | 3.73 | 7.21 | 10.53 | 13.18 | 14.21 |
| 6 mm Pb | ||||||
| 0.25 | 0.29 | 1.99 | 3.90 | 5.65 | 6.91 | 7.41 |
| 0.662 | 0.13 | 0.98 | 1.79 | 2.50 | 2.98 | 3.15 |
| 1.25 | 0.11 | 0.91 | 1.67 | 2.35 | 2.80 | 2.93 |
| 3 | 0.17 | 1.96 | 3.81 | 5.42 | 6.53 | 6.85 |
| 5 | 0.21 | 2.83 | 5.65 | 8.19 | 9.96 | 10.66 |
| 7 | 0.25 | 3.48 | 6.93 | 10.17 | 12.44 | 13.24 |
| 10 | 0.28 | 4.13 | 8.12 | 11.86 | 14.66 | 15.53 |
| 15 | 0.28 | 4.58 | 8.85 | 12.67 | 15.61 | 16.59 |
| 20 | 0.26 | 4.51 | 8.43 | 11.95 | 14.62 | 15.64 |
| 1 cm Pb | ||||||
| 0.25 | 0.29 | 1.99 | 3.89 | 5.66 | 6.93 | 7.42 |
| 0.662 | 0.13 | 0.97 | 1.78 | 2.49 | 3.01 | 3.16 |
| 1.25 | 0.11 | 0.91 | 1.68 | 2.35 | 2.84 | 2.94 |
| 3 | 0.17 | 2.02 | 4.00 | 5.76 | 6.93 | 7.37 |
| 5 | 0.22 | 2.96 | 6.03 | 8.76 | 10.70 | 11.45 |
| 7 | 0.25 | 3.72 | 7.50 | 10.96 | 13.36 | 14.22 |
| 10 | 0.29 | 4.55 | 8.92 | 12.99 | 15.87 | 16.83 |
| 15 | 0.30 | 5.24 | 9.96 | 14.14 | 17.15 | 18.40 |
| 20 | 0.28 | 5.27 | 9.88 | 13.67 | 16.49 | 17.59 |
| 2 cm Pb | ||||||
| 0.25 | 0.29 | 1.99 | 3.89 | 5.67 | 6.91 | 7.37 |
| 0.662 | 0.13 | 0.98 | 1.77 | 2.50 | 2.98 | 3.18 |
| 1.25 | 0.11 | 0.91 | 1.68 | 2.36 | 2.87 | 2.97 |
| 3 | 0.17 | 2.05 | 4.12 | 5.97 | 7.30 | 7.78 |
| 5 | 0.22 | 3.04 | 6.31 | 9.24 | 11.32 | 12.14 |
| 7 | 0.26 | 3.85 | 7.96 | 11.63 | 14.31 | 15.23 |
| 10 | 0.29 | 4.78 | 9.64 | 13.97 | 17.08 | 18.26 |
| 15 | 0.31 | 5.58 | 10.94 | 15.56 | 18.84 | 20.11 |
| 20 | 0.29 | 5.70 | 11.12 | 15.42 | 18.56 | 19.76 |
Multiply each table entry by 10–3 (e.g., the entry 5.39 means 5.39 × 10–3) with electrons cut-off = 100 keV and photons cut-off = 1 keV.
The statistical uncertainties are within ± 4% (95% confidence limit).