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Energy deposition portions in the paired air slabs for the low-energy X-ray beams of BIPM quality
| Location of the paired air slabs | Energy deposition portion (%) | ||||||
|---|---|---|---|---|---|---|---|
| Upper slab (mm) | Lower slab (mm) | Beam code | |||||
| BIPM10 | BIPM30 | BIPM25 | BIPM50b | BIPM50a | |||
| 35–40 | 30–35 | 98.87 | 93.81 | 93.06 | 79.56 | 65.88 | |
| 40–45 | 25–30 | 1.07 | 6.01 | 6.85 | 17.01 | 23.91 | |
| 45–50 | 20–25 | 0.02 | 0.14 | 0.07 | 2.72 | 7.50 | |
| 50–55 | 15–20 | 0.01 | 0.01 | 0.01 | 0.55 | 2.06 | |
| 55–60 | 10–15 | 0.01 | 0.01 | 0.01 | 0.12 | 0.51 | |
| 60–65 | 5–10 | 0.01 | 0.01 | 0.00 | 0.03 | 0.11 | |
| 65–70 | 0–5 | 0.00 | 0.00 | 0.00 | 0.01 | 0.03 | |
BIPM, Bureau International des Poids et Mesures.
The air slabs were piled symmetrically with the beam axis plane placed 35-mm-high from the collector electrode as the symmetry plane. The low-energy X-ray beams of BIPM quality were incident on the front face of the air box (see Fig. 4) and the beam size was 10-mm in diameter. The lengths and widths of the slabs were the same as those of the collector electrode, 15.8 mm and 70.0 mm, respectively.