Hegazy, Ehab

doi:10.21608/dusj.2024.297061.1073

"Assessment of Ionization Chamber Stability and Calibration Using Co-60 and Sr-90 Sources Used in Radiotherapy Dosimetry"

Document Type : Original research papers

Author

Ehab Hegazy

Associate professor of medical physics, Faculty of Applied Health Science Technology, Delta University for Science and Technology, Egypt.

10.21608/dusj.2024.297061.1073

Abstract

Ionization chambers are integral tools in radiation dosimetry, providing accurate measurements crucial for medical applications such as radiation therapy. Ensuring the stability of ionization chambers is essential to guarantee the precision and reliability of dose delivery in clinical settings. This study aimed to assess the stability of ionization chambers using Co-60 and Sr-90 radioactive sources for calibration, with a focus on understanding the effect of polarity on chamber performance. Two T34013 ionization chambers along with a PTW Farmer-type chamber were utilized for experimentation. The chambers were irradiated at various depths and doses using both Co-60 and Sr-90 sources within a water phantom to simulate clinical conditions accurately. Data acquisition and analysis were conducted, considering factors such as chamber response, recombination correction, and atmospheric correction. Statistical analysis revealed differences in chamber stability and performance, with Co-60 readings demonstrating greater stability compared to Sr-90 readings across different chamber types and doses. Moreover, the effect of polarity on chamber response was investigated, highlighting its significance in dosimetry applications. These findings contribute to the advancement of radiation dosimetry techniques, providing valuable insights for optimizing chamber calibration and ensuring accurate dose measurements in radiotherapy.

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