Developing next generation fast-timing photon-detectors

区分不同类型带电粒子的能力是大型强子对撞机LHCb实验将进行的测量计划的关键。内反射切伦科夫光探测器（TORCH）的目的是根据带电粒子从其产生点到下游9.5米处的定时探测器的飞行时间来分离带电粒子。在固定的动量下，不同类型的粒子将花费或多或少的时间来穿越距离，这取决于它们的质量。精确分离颗粒的关键是精确测量颗粒到达时间。TORCH项目旨在利用穿过石英棒的粒子发出的切伦科夫辐射作为定时信号。为了达到LHCb实验所需的精度，单个切伦科夫光子需要被计时到几十皮秒。快速光子定时由微通道板光电倍增管（MCP-PMT）阵列提供。然后可以组合来自多个光子的信息以实现对粒子飞行时间的非常精确的测量。最新的TORCH原型采用与英国领先的光子探测器设备制造商Photek Ltd合作生产的MCP-PMT。CASE学生将与沃里克大学和Photek的科学家和工程师一起工作，模拟和表征新一代MCP-PMT，这将需要科普在大型强子对撞机运行时看到的光子速率。对预期碰撞环境的模拟表明，该速率超出了现有设备的能力。

The ability to distinguish different types of charged particles is key to the programme of measurements that will be carried out with the LHCb experiment at the Large Hadron Collider. The Time Of internally Reflected Cherenkov light detector (TORCH) aims to separate charged particles based on their time-of-flight from their production point to a timing detector placed 9.5m downstream. At a fixed momentum, different types of particle will take more or less time to traverse the distance depending on how massive they are. Key to accurately separating the particles is a precise measurement of the particle arrival time. The TORCH project aims to use Cherenkov radiation emitted by particles traversing a quartz bar as a timing signal. To reach the precision needed for the LHCb experiment, individual Cherenkov photons needed to be timed to a few tens of picoseconds. The fast photon timing is provided by an array of micro-channel-plate photomultipliers (MCP-PMTs). Information from multiple photons can then be combined to achieve a very accurate measurement of a particles time-of-flight. The latest TORCH prototype features MCP-PMTs produced in collaboration with Photek Ltd, a leading UK manufacturer of photon detector devices. The CASE student will work with scientists and engineers at the University of Warwick and Photek on the simulation and characterisation a new generation of MCP-PMT that will be needed to cope with the rates of photons that will be seen when operating at the Large Hadron Collider. Simulations of the expected collision environment indicate that the rates are beyond the capabilities of existing devices.