Responses of GafChromic films for distribution of extremely high doses from synchrotron radiation

Using 10 and 30 keV photons from synchrotron radiation, we measured optical density curves of GafChromic films MD-55 and HD-810 and compared the results with those of 60Co gamma rays up to 500 kGy. The scanners used were a fluorescence digitizer and a color film scanner. In addition, the energy responses were measured between 10 and 100 keV. The values were 0.8 for HD-810 above 10 keV and 0.95 at 100 keV for MD-55, which decreased to 0.6 at 30 keV.