论文标题
基于地图的爱丽丝升级
The MAPS-based ITS Upgrade for ALICE
论文作者
论文摘要
LHC的Alice实验的内部跟踪系统（ITS）升级是基于CMOS Monolithic Active Pixel Sensor（MAPS）技术的第一个大区域（$ \ sim $ 10〜M $ $^2 $）硅顶点检测器，它结合了敏感的体积和前端读取逻辑，并在同一硅硅中组合。由于薄的传感器（50-100〜 $ $ m），这项技术允许降低材料预算（目标价值为0.3 \％），并且对冷却的需求有限，并结合了轻型的互连电路和支持结构。小像素螺距（$ \ sim $ 30〜 $μ$ m），层的位置（7个圆柱层，半径范围从2.3〜cm到距光束交互线的39.3 cm不等），并且有限的材料预算将为爱丽丝实验提供极为精确的跟踪分辨率。高速读数功能还将使爱丽丝在LHC运行〜3中预期的50〜KHz PB-PB碰撞率以50〜KHz PB-PB碰撞率收集大型数据样本。现已在地面组装的新的ITS目前正在经历一个详尽的预委托阶段，并具有独立的校准和宇宙射线数据研究，该阶段将于2020年4月在Alice探测器安装之前完成。本文将从施工和委托前阶段获得的经验以及为爱丽丝的数据收集的安装和准备计划提供的经验。新人在地图技术为未来应用程序的开发路径中所扮演的角色也将进行简要讨论。
The Inner Tracking System (ITS) Upgrade for the ALICE experiment at LHC is the first large-area ($\sim$10~m$^2$) silicon vertex detector based on the CMOS Monolithic Active Pixel Sensor (MAPS) technology, which combines sensitive volume and front-end readout logic in the same piece of silicon. This technology allows a reduced material budget (target value of 0.3\% on the innermost layers) thanks to the thin sensors (50-100~$μ$m) and limited need of cooling, in combination with light-material interconnection circuits and support structures. The small pixel pitch ($\sim$30~$μ$m), the location of the layers (7 cylindrical layers with radii ranging from 2.3~cm to 39.3~cm from the beam interaction line), and the limited material budget will provide the ALICE experiment with extremely precise tracking resolution. The high-rate readout capabilities will also enable ALICE to collect a large data sample at the 50~kHz Pb--Pb collision rate expected in the LHC Run~3. The new ITS, now assembled at the surface, is currently undergoing an exhaustive pre-commissioning phase with standalone calibration and cosmic ray data-taking, which will be completed by April 2020 before the installation in the ALICE detector. Experience gained from the construction and the pre-commissioning phase, and plans for the installation and preparation for the data-taking in ALICE will be presented in this paper. The role played by the new ITS within the development path of the MAPS technology for future applications will also be briefly discussed.
