Dosimetry for ~131Cs and ~125I seeds in solid water phantom using radiochromic EBT film

摘要

Purpose: To measure the 2D dose distributions with submillimeter resolution for ~131Cs (model CS-1 Rev2) and ~125I (model 6711) seeds in a Solid Water phantom using radiochromic EBT film for radial distances from 0.06 cm to 5 cm. To determine the TG-43 dosimetry parameters in water by applying Solid Water to liquid water correction factors generated from Monte Carlo simulations. Methods: Each film piece was positioned horizontally above and in close contact with a ~131Cs or ~125I seed oriented horizontally in a machined groove at the center of a Solid Water phantom, one film at a time. A total of 74 and 50 films were exposed to the~131Cs and ~125I seeds, respectively. Different film sizes were utilized to gather data in different distance ranges.