Neutron measurement is considered to be one of the major diagnostic methods in tokamak plasma. The neutron diagnostics provide key information on plasma physics, machine protection and control issues. In this article, the commonly used techniques of neutron emission diagnostics for tokamak plasma are presented. The requirements and limitations imposed on the diagnostic systems are discussed. Several basic techniques of total neutron yield and neutron spectrum measurements such as neutron counters, neutron activation technique, time-of-flight spectroscopy or magnetic proton recoil spectroscopy are described in a practical way, from a plasma diagnostician point of view. Primary physical quantities that can be derived from those measurements are pointed out and discussed.

中文翻译：

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托卡马克等离子体的中子诊断：从等离子体诊断师的角度

中子测量被认为是托卡马克等离子体的主要诊断方法之一。中子诊断提供有关等离子体物理、机器保护和控制问题的关键信息。本文介绍了托卡马克等离子体中子发射诊断的常用技术。对诊断系统的要求和限制进行了讨论。从等离子体诊断师的角度，以实用的方式描述了总中子产额和中子谱测量的几种基本技术，例如中子计数器、中子活化技术、飞行时间谱或磁质子反冲谱。指出并讨论了可以从这些测量中导出的主要物理量。