Study of the response of plastic scintillation detectors in small-field 6 MV photon beams by Monte Carlo simulations.
Study of the response of plastic scintillation detectors in small-field 6 MV photon beams by Monte Carlo simulations.
复制标题
通过蒙特卡罗模拟研究塑料闪烁探测器在小场 6 MV 光子束中的响应。
DOI：
10.1118/1.3554644
复制
发表时间：
2011
期刊：
影响因子：
3.8
通讯作者：
Beddar,Sam
中科院分区：
文献类型：
--
作者：
Wang,LilieLW;Beddar,Sam
PurposeTo investigate the response of plastic scintillation detectors (PSDs) in a 6 MV photon beam of various field sizes using Monte Carlo simulations.MethodsThree PSDs were simulated: A BC‐400 and a BCF‐12, each attached to a plastic‐core optical fiber, and a BC‐400 attached to an air‐core optical fiber. PSD response was calculated as the detector dose per unit water dose for field sizes ranging from down to for bothperpendicularandparallelorientations of the detectors to an incident beam. Similar calculations were performed for a CC01 compact chamber. The off‐axis dose profiles were calculated in the photon beam and were compared to the dose profile calculated for the CC01 chamber and that calculated in water without any detector. The angular dependence of the PSDs' responses in a small photon beam was studied.ResultsIn the perpendicular orientation, the response of the BCF‐12 PSD varied by only 0.5% as the field size decreased from to , while the response of BC‐400 PSD attached to a plastic‐core fiber varied by more than 3% at the smallest field size because of its longer sensitive region. In the parallel orientation, the response of both PSDs attached to a plastic‐core fiber varied by less than 0.4% for the same range of field sizes. For the PSD attached to an air‐core fiber, the response varied, at most, by 2% for both orientations.ConclusionsThe responses of all the PSDs investigated in this work can have a variation of only 1%–2% irrespective of field size and orientation of the detector if the length of the sensitive region is not more than 2 mm long and the optical fiber stems are prevented from pointing directly to the incident source.
