Relationship between RBE and depth dose for 23-MeV electrons.

A study comparing the RBE in depth of 23-MeV electrons was performed. A mouse sarcoma (KHT) maintained by serial passage in the C3H/HeJ female mouse was irradiated. Under the 23-MeV electron beam at the 100-percent and 14-percent isodose positions and under the 60Co beam at the 100-percent isodose position. The data failed to demonstrate a difference in biological effectiveness for the 23-MeV electron beam comparing the 14-percent isodose to the 100-percent isodose position.