title: Microdosimetric measurements and estimation of human cell survival for heavy-ion beams.
abstract: The microdosimetric spectra for high-energy beams of photons and proton, helium, carbon, neon, silicon and iron ions (LET = 0.5-880 keV/microm) were measured with a spherical-walled tissue-equivalent proportional counter at various depths in a plastic phantom. Survival curves for human tumor cells were also obtained under the same conditions. Then the survival curves were compared with those estimated by a microdosimetric model based on the spectra and the biological parameters for each cell line. The estimated alpha terms of the liner-quadratic model with a fixed beta value reproduced the experimental results for cell irradiation for ion beams with LETs of less than 450 keV/microm, except in the region near the distal peak.
authors.affiliation: Tokyo Institute of Technology, 4259, Nagatsuta-cho, Midori-ku, Yokohama 226-8502, Japan. y_kase@nirs.go.jp
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kase
authors.forename: Tatsuaki
authors.initials: T
authors.lastname: Kanai
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Matsumoto
authors.forename: Yoshiya
authors.initials: Y
authors.lastname: Furusawa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Okamoto
authors.forename: Toru
authors.initials: T
authors.lastname: Asaba
authors.forename: Makoto
authors.initials: M
authors.lastname: Sakama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Shinoda
mesh_terms: D002460:Cell Line; D002470:Cell Survival / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005347:Fibroblasts / Q000166:cytology* / Q000528:radiation effects*; D020450:Heavy Ions; D006801:Humans; D011829:Radiation Dosage; D011874:Radiometry / Q000295:instrumentation* / Q000379:methods; D012468:Salivary Gland Neoplasms / Q000473:pathology*