title: Performance of KCl:Eu2+ storage phosphor dosimeters for low-dose measurements.
abstract: Recent research has demonstrated that europium doped potassium chloride (KCl:Eu(2+)) storage phosphor material has the potential to become the physical foundation of a novel and reusable dosimetry system using either film-like devices or devices similar to thermoluminescent dosimeter chips. The purposes of this work are to quantify the performance of KCl:Eu(2+) prototype dosimeters for low-dose measurements and to demonstrate how it can be incorporated into clinical application for in vivo peripheral dose measurements. Pellet-style KCl:Eu(2+) dosimeters, 6 mm in diameter, and 1 mm thick, were fabricated in-house for this study. The dosimeters were read using a laboratory photostimulated luminescence detection system. KCl:Eu(2+) prototype storage phosphor dosimeter was capable of measuring a dose-to-water as low as 0.01 cGy from a 6 MV photon beam with a signal-to-noise ratio greater than 6. A pre-readout thermal annealing procedure enabled the dosimeter to be read within an hour post-irradiation. After receiving large accumulated doses (~10 kGy), the dosimeters retained linear response in the low-dose region with only a 20% loss of sensitivity comparing to a fresh sample (zero Gy history). The energy dependence encountered during low-dose peripheral measurements could be accounted for via a single point outside-field calibration per each beam quality. With further development the KCl:Eu(2+-)-based dosimeter could become a versatile and durable dosimetry tool with large dynamic range (sub-cGy to 100 Gy).
authors.affiliation: Department of Radiation Oncology, Washington University School of Medicine, 4921 Parkview Place, Campus Box 8224, St. Louis, MO 63110, USA.
authors.forename: H Harold
authors.initials: HH
authors.lastname: Li
authors.forename: Zhiyan
authors.initials: Z
authors.lastname: Xiao
authors.forename: Rachael
authors.initials: R
authors.lastname: Hansel
authors.forename: Nels
authors.initials: N
authors.lastname: Knutson
authors.forename: Deshan
authors.initials: D
authors.lastname: Yang
mesh_terms: D005063:Europium / Q000737:chemistry*; D011189:Potassium Chloride / Q000737:chemistry*; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*; D013997:Time Factors
chemical_list: D005063:Europium; D011189:Potassium Chloride