Gafchromic XRCT, radiochromic film is assessed over a broad energy range, from kilovoltage to megavoltage x rays for variations in reflected optical density to dose response. A large energy dependence was found with reflected optical density output for the same delivered dose varying from 7.8±0.35 at 25.5keV (50kVp) peaking at 12.1±0.5 at 54keV (125kVp) to 0.975±0.03 at 2300keV (10MV) when norm...

For megavoltage photon radiation, the fundamental dosimetry characteristics of Gafchromic EBT3 film were determined in 60Co gamma ray beam with addition of experimental and Monte Carlo (MC)-simulated energy dependence of the film for 6 MV photon beam and 6 MeV, 9 MeV, 12 MeV, and 16 MeV electron beams in water phantom. For the film read-out, two phase correction of scanner sensitivity was appli...

Background: The accuracy and the reproducibility of radiotherapy can be provided by using immobilization devices such as thermoplastic masks. In head and neck cancer radiotherapy, the patients are mostly immobilized by using thermoplastic masks. In this study, the effect of the thermoplastic mask to the surface and buildup region doses was investigated by using Markus parallel plate ion chamber...

The purpose of this study was to compare dose measurements using ion chamber and radiochromic film dosimetry for a 35-keV synchrotron beam useful for Auger electron therapy. A 1.3-GeV electron beam, transported through a 3-pole superconducting wiggler magnet, produced a polychromatic photon beam from which a 35-keV beam (3.3 mm Al HVL) was selected using a monochromator. A 2.8 cm x 2.5 cm field...

Radiochromic film has become an important tool to verify dose distributions for intensity-modulated radiotherapy (IMRT) and quality assurance (QA) procedures. A new radiochromic film model, EBT3, has recently become available, whose composition and thickness of the sensitive layer are the same as those of previous EBT2 films. However, a matte polyester layer was added to EBT3 to prevent the for...

The effects of temperature on real time changes in optical density (DeltaOD) of GAFCHROMIC EBT film were investigated. The spectral peak of maximum change in absorbance (lambdamax) was shown to downshift linearly when the temperature of the film was increased from 22 to 38 degrees C. The DeltaOD values were also shown to decrease linearly with temperature, and this decrease could not be attribu...