Abstract

The European Spallation Source is being built in Lund, Sweden and it’s planned to be the brightest pulsed spallation source for thermal and cold neutrons (<1 eV). Neutrons will be produced by a 2 GeV accelerated proton beam hitting a tungsten target wheel, then they are moderated by liquid hydrogen and water based moderator system and delivered to 42 beam-ports. Neutrons are transported via reflections to a set of instruments connected to the beam-ports through neutron guides. Undesired fast neutrons can cause a radiation safety issue, since they can find their way down the beam-lines and thus generate a large dose. A designed shielding structure is needed to minimize such effect during the beam at the target phase. We present the results of neutronic calculations to optimize the guide shielding for the VESPA instrument.

中文翻译：

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VESPA仪器在欧洲散裂源处的屏蔽设计的中子学计算

摘要

欧洲散裂源正在瑞典的隆德建造，并计划成为热中子和冷中子（<1 eV）中最亮的脉冲散裂源。中子将由2 GeV加速质子束撞击钨靶轮产生，然后由液氢和水基缓和剂系统缓和并输送至42个束口。中子通过反射传输到通过中子导管与束口相连的一组仪器。不需要的快速中子会导致辐射安全问题，因为它们会沿着束线找到方向并因此产生大剂量。需要一种设计的屏蔽结构来最小化在目标相位的光束期间的这种影响。我们介绍了中子学计算的结果，以优化VESPA仪器的导向罩。