Penetration Depth of the Radiation Dose and Dose Yield for Low Energy Electron Beam Accelerators

Introduction

The radiochemical induced reaction in an irradiated product is determined by the
absorbed radiation dose. The penetration depth of dose has to be high enough fora
homogeneous dose distribution in the product The ability to deliver dose is
determined through the efficiency or the yield factor of a processor. Penetration
depths can be derived from depth dose profiles, which depend on the acceleration
voltage.

An approximation function for depth dose profiles is developed. By inclusion of the
window thickness and the air gap this function is of universal validity for light
elements in a voltage range from 150 to 350 kV.

The inherent energy of electron beams is defined by the product of acceleration
voltage, beam current and irradiation time. A function for the yield factor is derived
from the part of energy, which is transferred to irradiated matter. It only depends on
geometrical factors of the accelerator and depth dose profiles. The function is in very
good agreement with direct measurements.