标题： BESIII实验用圆柱形GEM探测器的测试束结果 显示英文标题

标题： Test beam results of a Cylindrical GEM detector for the BESIII experiment

摘要： 气体探测器是非常轻便的仪器，用于高能物理中测量粒子的属性：位置和动量。 通过高压电场可以使用气体电子倍增器（GEM）技术来探测带电粒子，并利用其特性构建大面积探测器，例如BESIII的新IT。 目前GEM制造技术可以制造非常大的GEM薄膜（最大达50x100$\mathrm{cm}^2$），并且由于这些薄膜的厚度很小，可以将其塑造成所需形状：因此提出了圆柱形气体电子倍增器（CGEM）。 基于Rohacell（一种PMI泡沫）的创新构造技术将为阴极和阳极提供坚固性，且对材料预算的影响非常小。 整个探测器由粘贴在边缘的Permaglass环支撑。 这些环用于组装CGEM，同时还配有专用的垂直插入系统，并且它们还容纳探测器上的电子设备。 阳极通过锯齿状读出方式进行了改进，以最小化相邻条带之间的电容。 该探测器的机械挑战要求整个几何结构在全部区域内具有几百分之一毫米的精度。 在本次贡献中，将介绍构造技术的概述、通过实现CGEM验证该技术以及其首次测试。 这些活动是在BESIIICGEM项目（645664）框架内进行的，该项目由欧洲委员会在H2020-RISE-MSCA-2014行动中资助。 显示英文摘要

摘要： Gas detector are very light instrument used in high energy physics to measure the particle properties: position and momentum. Through high electric field is possible to use the Gas Electron Multiplier (GEM) technology to detect the charged particles and to exploit their properties to construct a large area detector, such as the new IT for BESIII. The state of the art in the GEM production allows to create very large area GEM foils (up to 50x100 $\mathrm{cm}^2$) and thanks to the small thickness of these foils is it possible to shape it to the desired form: a Cylindrical Gas Electron Multiplier (CGEM) is then proposed. The innovative construction technique based on Rohacell, a PMI foam, will give solidity to cathode and anode with a very low impact on material budget. The entire detector is sustained by Permaglass rings glued at the edges. These rings are used to assembly the CGEM, together with a dedicated Vertical Insertion System and moreover they host the On-Detector electronic. The anode has been improved w.r.t. the state of the art through a jagged readout that minimize the inter-strip capacitance. The mechanical challenge of this detector requires a precision of the entire geometry within few hundreds of microns in the whole area. In this contribution an overview of the construction technique, the validation of this technique through the realization of a CGEM, and its first tests will be presented. These activities are performed within the framework of the BESIIICGEM Project (645664), funded by the European Commission in the action H2020-RISE-MSCA-2014.