Valency conversion of samarium ions under high dose synchrotron generated X-ray radiation

摘要: Microbeam Radiation Therapy (MRT) is a synchrotron based technique for cancer treatment. During MRT tumours are irradiated with micro-planar arrays of synchrotron-generated X-rays. The quality assurance such depends on the accurate measurement very high dose levels (>1000 Gy) together precise distribution over scale few microns. For applications we need to have dynamic range, high-dose detector spatial resolution. As part work towards development examined X-ray radiation induced conversion rare-earth ions, especially Sm3+ Sm2+, embedded in suitable media. We exposed variety doped media, from single crystals glass-ceramics, at Canadian Light Source examine whether could convert ion valency. irradiation was carried out bending magnet beamline using filtered white beam spectrum peaking 50 keV. used distinctly different signatures photoluminescence emission spectra two valency states identify ions and has taken place. report results these experiments, which show that Sm2+ not universal much host material. discuss possible reasons presence lack Sm-ions, challenges must be overcome develop high-resolution, detector. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)