标题： ALICE内部追踪系统的升级 显示英文标题

标题： Upgrade of the Inner Tracking System of ALICE

摘要： ALICE的内跟踪系统（ITS）的升级计划在2019-2020年LHC的第二次长停机期间进行。 停机后的ALICE物理程序要求ITS具有改进的跟踪能力，在非常低的横向动量下具有改进的碰撞参数分辨率，并且读出速率有显著提高。 为了满足这些要求，当前的ITS将被七层单片有源像素传感器取代。 新探测器将尽可能靠近相互作用点，距离仅为23毫米，并且材料预算将显著减少。 已经开发了传感器的多个原型，以测试传感器设计的不同方面，包括具有模拟和数字读出的原型，以及小尺寸和最终尺寸的传感器。 这些原型已在实验室测试和测试束设施中进行了全面表征，包括对传感器辐射硬度的研究。 本次报告概述了当前研究和开发的状况，重点介绍了像素传感器以及最新原型的表征。 显示英文摘要

摘要： The upgrade of the Inner Tracking System (ITS) of ALICE is planned for the second long shutdown of the LHC in 2019-2020. The ALICE physics program after the shutdown requires the ITS to have improved tracking capabilities and improved impact parameter resolution at very low transverse momentum, as well as a substantial increase in the readout rate. To fulfill these requirements the current ITS will be replaced by seven layers of Monolithic Active Pixel Sensors. The new detector will be moved as close as 23 mm to the interaction point and will have a significantly reduced material budget. Several prototypes of the sensor have been developed to test different aspects of the sensor design including prototypes with analog and digital readout, as well as small and final-size sensors. These prototypes have been thoroughly characterized both in laboratory tests and at test beam facilities including studies on the radiation hardness of the sensors. This contribution gives an overview of the current status of the research and development with a focus on the pixel sensors and the characterization of the latest prototypes.