What is the required equilibrium wall thickness for the chamber used for beam up measurements at 60Co energy?

The required equilibrium wall thickness for the chamber used for beam up measurements at 60Co energy is specifically related to achieving the necessary conditions for accurate dosimetry and ensuring the chamber can properly register the beam energy.

For 60Co, which emits gamma radiation predominantly at 1.17 MeV and 1.33 MeV, the interaction of these photons with matter plays a significant role in the response of the chamber. The thickness of the wall must be sufficient to achieve electronic equilibrium, meaning that the number of charged particles produced in the wall from the photon interactions equals the number of charged particles escaping to the outside.

A wall thickness of 500 mg/cm² is optimal for ensuring that the ionization chamber delivers accurate readings at this energy, as it provides enough material for the photons to interact while not being so thick as to cause significant attenuation of the beam. This ensures that the measurement reflects the true dosage of the radiation being delivered, leading to reliable dosimetric calculations. Using a wall that is too thin may not capture enough interactions, while a wall that is too thick could lead to over-attenuation and erroneous results. Thus, the specified equilibrium wall thickness of 500 mg/cm² is designed to meet the requirements for accurate dos