Proton therapy is an advanced method for treating cancerous tumors, and its adoption has expanded significantly in recent years. The production of high-energy protons, however, may result in the creation of secondary neutrons and gamma rays. Hence, ensuring radiation safety at proton therapy centers is crucial, with shielding playing a vital role. This study aimed to evaluate the efficacy of the shielding implemented at the Provision Proton Therapy center in Knoxville, TN, USA. For this purpose, we measured and compared gamma ray radiation levels within the treatment room and the facility's roof. These measurements were conducted using a NaI(Tl) scintillator detector. The PHITS Monte Carlo code was used to deconvolute the incident spectrum using detector response functions. Findings reveal that the facility's shielding effectively protects the general public from gamma ray radiation, with the effective dose within the treatment room being minimal and dose on the roof was comparable to background radiation levels. However, it is important to note that this study did not address the issue of secondary neutron radiation field, which is an important aspect of dose and radiation safety in proton therapy centers.

中文翻译：

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在质子治疗中心进行剂量测量。

质子疗法是一种治疗癌性肿瘤的先进方法，近年来其采用率显着扩大。然而，高能质子的产生可能会导致二次中子和伽马射线的产生。因此，确保质子治疗中心的辐射安全至关重要，其中屏蔽起着至关重要的作用。本研究旨在评估美国田纳西州诺克斯维尔质子治疗中心实施的屏蔽效果。为此，我们测量并比较了治疗室和设施屋顶内的伽马射线辐射水平。这些测量是使用 NaI(Tl) 闪烁体探测器进行的。PHITS 蒙特卡罗代码用于使用探测器响应函数对入射光谱进行解卷积。研究结果表明，该设施的屏蔽有效地保护了公众免受伽马射线辐射，治疗室内的有效剂量极小，屋顶上的剂量与背景辐射水平相当。然而，值得注意的是，这项研究并没有解决二次中子辐射场的问题，而二次中子辐射场是质子治疗中心剂量和辐射安全的一个重要方面。