用Markus平行板电离室、Gafchromic EBT3膜和MOSFET探测器测量高能光子束表面和积聚区剂量
Surface and buildup region dose measurements with Markus parallel-plate ionization chamber, Gafchromic EBT3 film and MOSFET detector for high energy photon beams
摘要：
本研究的目的是调查表面和建立区域剂量为6 MV和15 MV光子束使用马库斯平行板电离室，GafChromic EBT 3膜，和MOSFET探测器不同的字段大小和光束角度。在水等效固体体模中，在表面和6 MV和15 MV光子束的积聚区域中，在100 cm的源-探测器距离处，针对5 x 5、10 x 10和20 x 20 cm 2的射野尺寸和0、30、60和80光束角度进行测量。对于Markus室、EBT 3膜和MOSFET探测器，发现使用6 MV光子束对于10 × 10 cm 2场尺寸的表面剂量分别为20.3%、18.8%和25.5%。对于Markus室、EBT 3膜和MOSFET探测器，使用15 MV光子束对于10 × 10 cm 2场尺寸的表面剂量分别为14.9%、13.4%和16.4%。所有剂量计的表面剂量随射野大小而增加。随着入射辐射束的角度变得更加倾斜，表面剂量增加。剂量计的有效测量深度各不相同;因此，测量结果可能不同。该问题可能导致表面和累积剂量测定错误，必须予以考虑。
英文摘要：
The aim of the study was to investigate surface and buildup region doses for 6MV and 15MV photon beams using a Markus parallel-plate ionization chamber, GafChromic EBT3 film, and MOSFET detector for different field sizes and beam angles. The measurements were made in a water equivalent solid phantom at the surface and in the buildup region of the 6MV and 15MV photon beams at 100 cm source-detector distance for 5 x 5, 10 x 10, and 20 x 20 cm2 field sizes and 0, 30, 60, and 80 beam angles. The surface doses using 6MVphoton beams for 10 x 10 cm2 field size were found to be 20.3%, 18.8%, and 25.5% for Markus chamber, EBT3 film, and MOSFET detector, respectively. The surface doses using 15MV photon beams for 10 x 10 cm2 field size were found to be 14.9%, 13.4%, and 16.4% for Markus chamber, EBT3 film, and MOSFET detector, respectively. The surface dose increased with field size for all dosimeters. As the angle of the incident radiation beam became more oblique, the surface dose increased. The effective measurement depths of dosimeters vary; thus, the results of the measurements could be different. This issue can lead to mistakes at surface and buildup dosimetry and must be taken into account.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
