[Characterization of Small Volume Plastic Scintillation Detector].

Area of Science:

• Medical Physics
• Radiation Oncology
• Detector Technology

Background:

• Radiation detectors are crucial for quality assurance in high-precision external beam radiotherapy.
• Commercial plastic scintillation detectors for MeV X-ray measurement are now available.

Purpose of the Study:

• To evaluate a commercial plastic scintillation detector's performance.
• To compare its dose linearity, dose rate dependence, and output coefficient against ionization chambers and semiconductor detectors.
• To assess performance across various X-ray energies and with/without flattening filters.

Main Methods:

• Performance evaluation of a plastic scintillation detector.
• Comparative analysis with ionization chambers and semiconductor detectors.
• Testing under different X-ray energies and flattening filter conditions.

Main Results:

• All tested detectors demonstrated linear dose response.
• The plastic scintillation detector exhibited increased dose rate dependence at lower dose rates.
• Output coefficients were comparable to semiconductor detectors, even in small fields.

Conclusions:

• Plastic scintillation detectors are suitable for dose verification in high-precision external beam radiotherapy.
• Caution is advised during low dose rate measurements due to observed dependence.