Neutron Therapy: An Experimental System in Radiooncology. The history of the use of neutrons in radiotherapy will be revisited by focusing on the ideas, theories and experiments that led to first clinical studies. For addressing epistemological questions regarding biological effects of fast neutrons, the notion of an "experimental system" is employed and its evolution over time discussed. Taking up the analytical framework of Hans-Jörg Rheinberger, biological effects and the physical instrument "cyclotron" are conceptualized in terms of epistemic and technical objects. It is shown that the epistemic object "biological effects of neutrons" could never reach the status of a technical object and - more strikingly - that the cyclotron itself returned to being an epistemic object in the context of medicine. So there is a misunderstanding of the different roles epistemic and technical objects have to play in the framework of an experimental system. This misunderstanding led to today's highly controversial discussions about the application of neutrons in radiotherapy.

中文翻译：

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Die Neutronentherapie：Ein Experimentalsystem der Radioonkologie

中子治疗：放射肿瘤学实验系统。通过关注导致首次临床研究的想法、理论和实验，将重新审视中子在放射治疗中的使用历史。为了解决有关快中子生物学效应的认识论问题，采用了“实验系统”的概念，并讨论了其随时间的演变。在 Hans-Jörg Rheinberger 的分析框架中，生物效应和物理仪器“回旋加速器”在认知和技术对象方面被概念化。结果表明，认知对象“中子的生物效应”永远无法达到技术对象的状态，而且——更引人注目的是——回旋加速器本身在医学背景下又回到了认知对象。因此，人们误解了认知对象和技术对象在实验系统框架中必须扮演的不同角色。这种误解导致了今天关于中子在放射治疗中的应用的极具争议的讨论。