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arXiv · 2211.00413

Construction of a radiation beam scanner and investigation of volume averaging correction factor effects on beam-profile

Joonas Tikkanen·Jan Morelius·Teemu Siiskonen
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Abstract

In radiation beam-profile measurements, an accurate positioning of the detector with high position resolution is essential. For this purpose, we built a scanning device capable of moving a detector in three dimensions using mainly parts from a commercial 3D-printer. The accuracy and repeatability of movement was tested with caliper, laser displacement sensor, and repeated $^{60}$Co beam-profile measurements in a water phantom. The results from the caliper and the sensor showed position accuracy for the scanner to be better than $\pm$150 $μ$m. The standard deviation of the error in position from laser sensor measurements was approximately 30 $μ$m and the beam profile scans showed a maximum deviation from the mean position of 50 $μ$m. The effect of volume averaging correction factors on $^{60}$Co beam-profile was investigated with two different sized ionization chambers. The differences in the profiles were reduced significantly after applying the correction factors.

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Joonas Tikkanen, Jan Morelius, Teemu Siiskonen. 2022-11-01. Construction of a radiation beam scanner and investigation of volume averaging correction factor effects on beam-profile. https://arxiv.org/abs/2211.00413

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