A quality control method for detecting energy changes of medical accelerators

Area of Science:

• Medical physics
• Accelerator technology
• Nuclear medicine

Background:

• Accurate electron beam energy is critical for consistent medical accelerator output.
• Existing quality control methods may lack sensitivity or simplicity.
• Ensuring precise electron energy is vital for effective radiation therapy.

Purpose of the Study:

• To develop a simple and sensitive method for detecting electron energy variations in medical accelerators.
• To establish a quality control technique for X-ray beams with endpoint energies between 15.7 and 25 MeV.
• To quantify the sensitivity of the proposed method for detecting electron energy changes.

Main Methods:

• Utilizing the photoactivation of Oxygen-16 (16O) and Nitrogen-14 (14N) in ammonium nitrate.
• Measuring the induced radioactivity in the oxygen and nitrogen components.
• Calculating the ratio of activity induced in oxygen to that produced in nitrogen.

Main Results:

• The ratio of induced activity (oxygen/nitrogen) serves as a reliable indicator of electron beam energy.
• The method is sensitive enough to detect electron energy changes of approximately 0.2 MeV.
• This technique is applicable to X-ray beams generated by medical accelerators within the specified energy range.

Conclusions:

• The described photoactivation method offers a simple, sensitive, and effective quality control for medical accelerator electron beam energy.
• This technique can be readily implemented for routine monitoring, enhancing treatment accuracy.
• The findings support the use of ammonium nitrate as a dosimetric material for electron energy verification.