Development of a wavelength-separated type scintillator with optical fiber (SOF) dosimeter to compensate for the Cerenkov radiation effect.
Bottom Line: The scintillator of the current SOF dosimeter is a 1-mm diameter hemisphere.A dichroic mirror was used for separating input light signals.Individual signal counting was performed for high- and low-wavelength light signals.
Affiliation: Department of Medical Physics and Engineering, Graduate School of Medicine, Hokkaido University, N-15 W-7 Kita-ku, Sapporo Hokkaido, 060-8638, Japan email@example.com.Show MeSH
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Mentions: In this study, two probes with differing sensitivities were used. Probe #1 is a normal probe with an estimated volume of 0.234 mm3, while probe #2 has a smaller scintillator with a volume of 0.106 mm3 to enhance the Cerenkov radiation effect. In order to assess the accuracy of the scintillation–Cerenkov signal separation method, measurements were performed with the geometry shown in Fig. 5. A 30 × 30 × 2 cm3 PMMA phantom with a guide sleeve was placed at a 5-cm distance from the phantom center, which is the location of the SOF dosimeter probe. For gathering scattering gamma rays, 5-cm-thick Mix-DP phantoms were placed on both sides of the PMMA phantom as shown in Fig. 5. Zero degrees is defined toward the tip of the SOF dosimeter. Measurements were acquired at 0, 30, 60, 90, 120, 150, 160, 170 and 180°. The 180° position was the closest to the 192Ir source; the distance was ∼2 mm. Acquisition times for each measurement point were 20 s, repeated five times. Calibration measurements were acquired for 60 s, repeated 10 times.Fig. 5.
Affiliation: Department of Medical Physics and Engineering, Graduate School of Medicine, Hokkaido University, N-15 W-7 Kita-ku, Sapporo Hokkaido, 060-8638, Japan firstname.lastname@example.org.