title: Induced radioactive nuclides of 10-MeV radiotherapy accelerators detected by using a portable HP-Ge survey meter.
abstract: The radioactivation of linear accelerator components for radiation therapy is interest for radiation protection in general, and particularly, when decommissioning these structures. The energy spectra of gamma rays emitted from the heads of two accelerator models, EXL-15SP and Clinac iX, after 10-MeV X-ray irradiation, were measured using a high-purity germanium semiconductor survey meter. After spectrum analyses, activities of (24)Na, (28)Al, (54)Mn, (56)Mn, (57)Ni, (58)Co, (60)Co, (64)Cu, (65)Zn, (122)Sb, (124)Sb, (181)W, (187)W, (196)Au, and (198)Au were detected. One centimetre deep dose-equivalent rate of the heads of the linear accelerator was measured using the survey meter. The dose rate decreased to ∼10 % of its initial rate after 1 week. Long-term activations were few, the radioactivity level was low, and a cooling time of several days was effective for reducing dose rate to an acceptable level for decommissioning.
authors.affiliation: Department of Radiological Sciences, School of Health Sciences,  Ibaraki Prefectural University of Health Science, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394,  Japan.
authors.forename: Toshioh
authors.initials: T
authors.lastname: Fujibuchi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Obara
authors.forename: Ichiro
authors.initials: I
authors.lastname: Yamaguchi
authors.forename: Masaya
authors.initials: M
authors.lastname: Oyama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Watanabe
authors.forename: Takeji
authors.initials: T
authors.lastname: Sakae
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Katoh
mesh_terms: D004867:Equipment Design; D005720:Gamma Rays; D005857:Germanium; D006801:Humans; D010315:Particle Accelerators; D011835:Radiation Protection / Q000295:instrumentation*; D011874:Radiometry / Q000295:instrumentation*; D011882:Radiotherapy, High-Energy / Q000295:instrumentation*
chemical_list: D005857:Germanium