Assessment of the effects of radiation type and energy on the calibration of TLD-100

Document Type: Original Paper

Authors

1 Medical Physics Department, Medical Physics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.

2 Medical Physics Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran

3 Student Research Committee, Mashhad University of Medical Sciences, Mashhad, Iran - Department of Medical Physics, Faculty of Medicine, University of Medical Sciences, Mashhad, Iran

Abstract

Introduction: In radiation therapy, knowing the dose rates to healthy organs and tumors is beneficial, and thermoluminescent dosimeter (TLD) allows for this possibility. This study was aimed at determining the dose-response differences of TLDs in various types of radiation, energy levels, and dose rate calibrated with other types of radiation beams and energy and dose levels.
Materials and Methods: In this study, LiF:Mg,Ti (TLD-100) was used for dosimetry. Photon and electron irradiation was performed by Elekta Precise Linear Accelerator. First, TLDs were calibrated in three different groups of 6 MV photon, 6 MeV electron, and 60Co teletherapy photon beam with 50 cGy dose. Next, each group was irradiated with 6 MV photon, 6 MeV electron, and 60Co teletherapy photon beam separately at three different dose levels of 20, 60, and 100 cGy.
Results: TLDs calibrated with electron were significantly different at all dose levels and with all types of radiation from TLDs calibrated with photon or 60Co teletherapy photon beam (P=0.000). P-value of the TLDs calibrated with 6 MV photon versus 60Co was less than 0.94. The maximum standard deviation belonged to 100 cGy irradiation, while the least pertained to 20 cGy irradiation.
Conclusion: Calibration of TLDs depends on the type of radiation.

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References

 

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