Preliminary results of the Gas Electron Multiplier (GEM) as real-time beam monitor in hadron therapy

详细信息    查看全文

• 作者：E. Aza^a ; ^b ; ^{eleni.aza@cern.ch" class="auth_mail" title="E-mail the corresponding author} ; M. Ciocca^c ; F. Murtas^a ; ^d ; S. Puddu^a ; ^e ; M. Pullia^c ; M. Silari^a
• 关键词：Beam monitor ; Hadron therapy ; GEM Detector ; Radiochromic film
• 刊名：Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
• 出版年：2017
• 出版时间：1 January 2017
• 年：2017
• 卷：841
• 期：Complete
• 页码：65-71
• 全文大小：754 K

文摘

The use of proton and carbon ion beams in cancer therapy (also known as hadron therapy) is progressively growing worldwide due to their improved dose distributions, sparing of healthy tissues and (for carbon ions) increased radiobiological effectiveness especially for radio-resistant tumours. Strict Quality Assurance (QA) protocols need to be followed for guaranteeing the clinical beam specifications. The aim of this study was to assess the performance of a gaseous detector based on the Gas Electron Multiplier (GEM) technology for measuring the beam spot dimensions and the homogeneity of the scanned irradiation field, which are daily QA tasks commonly performed using radiochromic films. Measurements performed at the National Centre for Oncological Hadron Therapy (CNAO) in Pavia (Italy) showed that the detector is able to monitor the 2D beam image on-line with a pad granularity of 2 mm and a response proportional to the number of delivered particles. The dose homogeneity was measured with low deviation from the results obtained with radiochromic films.