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The LET spectra at different penetration depths along secondary 9C and 11C beams
https://repo.qst.go.jp/records/43620
https://repo.qst.go.jp/records/4362066d4c4c0-524d-4f85-b670-eecd55cb1edf
Item type | 学術雑誌論文 / Journal Article(1) | |||||
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公開日 | 2005-01-13 | |||||
タイトル | ||||||
タイトル | The LET spectra at different penetration depths along secondary 9C and 11C beams | |||||
言語 | ||||||
言語 | eng | |||||
資源タイプ | ||||||
資源タイプ識別子 | http://purl.org/coar/resource_type/c_6501 | |||||
資源タイプ | journal article | |||||
アクセス権 | ||||||
アクセス権 | metadata only access | |||||
アクセス権URI | http://purl.org/coar/access_right/c_14cb | |||||
著者 |
Li, Qiang
× Li, Qiang× Komori, Masataka× Kanai, Tatsuaki× Kitagawa, Atsushi× Urakabe, Eriko× Kanazawa, Mitsutaka× Tomitani, Takehiro× Satou, Shinji× 李 強× 小森 雅孝× 金井 達明× 北川 敦志× 新谷 恵理子× 金澤 光隆× 富谷 武浩× 佐藤 眞二 |
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抄録 | ||||||
内容記述タイプ | Abstract | |||||
内容記述 | Qwing to the potentially therapeutic enhancement of delayed particles in treating malignant diseases by radioactive 9C-ion beam, LET spectra at different penetration depths for a 9C beam with 5% momentum spread, produced in the secondary beam line (SBL) at HIMAC, were measured with a multi-wire parallel-plate proportional counter. To compare these LET spectra with those of a therapeutic 12C beam under similar conditions, the 12C beam was replaced with an 11C beam, yielded in the SBL as well and having almost the same range as that of the 9C beam. The LET spectra of the 9C beam and its counterpart, i.e. the 11C beam, at various depths were compared, especially around the Bragg peak regions. The results show that nearby the Bragg peak lower LET components decreased in the LET spectra of the 9C beam while extra components between the LET peak caused by the primary beam and the lower components due to the fragments could be observed. These additional contributions in the LET spectra could be attributed to parts of the emitted particles from the radioactive 9C ions with suitable conditions regarding the LET counter. Integrating these LET spectra in different manners, depth-dose and dose-averaged LET distributions were obtained for the 9C and 11C beams, forming the basic data sets for further studies. In general, the depth-dose distributions of the 9C and 11C beams are comparative, i.e. almost the same peak-to-plateau ratio. The ratio for the 9C beam, however, has room to increase due to the geometric structure limitation of the present detector. The dose-averaged LETs along the beam penetration are always lower for the 9C beam than for the 11C beam except at the falloff region beyond the Bragg peak. Applying the present depth-dose and dose-averaged LET data sets as well as the essential radiobiological parameters obtained with 12C beams previously for HSG cells, an estimate concerning the HSG cell surviving effects along the penetration of the 9C and 11C beams shows that lower survival fractions for the 9C beam at the distal part of the Bragg peak, corresponding to the stopping retion of the incoming 9C ions, can be expected when the same entrance dose is given. It is still hard to appreciate the potential of 9C beams in cancer therapy based on the present LET spectrum measurement, but it provides a substantial basis for upcoming radiobiological experiments. | |||||
書誌情報 |
Physics in Medicine and Biology 巻 49, p. 5119-5133, 発行日 2004-10 |
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ISSN | ||||||
収録物識別子タイプ | ISSN | |||||
収録物識別子 | 0031-9155 |