论文标题
CMS精度质子光谱仪的时序系统：运行2的性能，未来升级和传感器辐射硬度研究
The CMS Precision Proton Spectrometer timing system: performance in Run 2, future upgrades and sensor radiation hardness studies
论文作者
论文摘要
可以通过将中央检测器的信息与精度质子光谱仪（PPS）相结合，可以在CMS中研究中央独家过程。 PPS探测器在距交互点超过200 m以上的对称放置可以检测到与该相互作用的散射质子。 PPS在CMS实验中完全集成时，以高光度的数据获取数据。在LHC运行期间，收集的数据的总量对应于100 fb $^{ - 1} $2。PPS由3D硅跟踪站组成，以及测量质子的位置和方向及其飞行时间的定时检测器，高精度。探测器托管在特殊的可移动真空室，罗马盆中，该盆地放置在LHC梁管的一级真空中。传感器与光束几毫米的距离达到了距离。检测器必须在真空中运行，并且必须能够维持高度不均匀的照射：运行2中使用的传感器积累了一个集成剂量，其局部峰为$ \ sim 5 \ cdot 10^{15} $ protons/cm $ $^2 $。正时系统是用高纯度SCCVD钻石传感器制成的。一个具有两个钻石晶体的新体系结构与同一电子通道并行读取，以增强检测器性能。在本文中，在对PPS检测器的一般概述之后，我们详细描述了时序系统。将传感器和专用扩增链与信号数字化技术一起描述。报告了探测器在运行2中的性能。最近，运行2中使用的传感器已在DESY的专用测试光束中测试了效率和计时性能。报道了辐射损伤的初步结果。 LHC Run 3的计时系统的重要升级正在进行，目的是达到比30 PS更好的最终时机分辨率；他们还在这里讨论。
Central exclusive processes can be studied in CMS by combining the information of the central detector with the Precision Proton Spectrometer (PPS). PPS detectors, placed symmetrically at more than 200 m from the interaction point, can detect the scattered protons that survive the interaction. PPS has taken data at high luminosity while fully integrated in the CMS experiment. The total amount of collected data corresponds to more than 100 fb$^{-1}$ during the LHC Run 2. PPS consists of 3D silicon tracking stations as well as timing detectors that measure both the position and direction of protons and their time-of-flight with high precision. The detectors are hosted in special movable vacuum chambers, the Roman Pots, which are placed in the primary vacuum of the LHC beam pipe. The sensors reach a distance of few mm from the beam. Detectors have to operate in vacuum and must be able to sustain highly non-uniform irradiation: sensors used in Run 2 have accumulated an integrated dose with a local peak of $\sim 5 \cdot 10^{15}$ protons/cm$^2$. The timing system is made with high purity scCVD diamond sensors. A new architecture with two diamond crystals read out in parallel by the same electronic channel has been used to enhance the detector performance. In this paper, after a general overview of the PPS detector, we describe the timing system in detail. The sensor and the dedicated amplification chain are described, together with the signal digitization technique. Performance of the detector in Run 2 is reported. Recently the sensors used in Run 2 have been tested for efficiency and timing performance in a dedicated test beam at DESY. Preliminary results on radiation damage are reported. Important upgrades of the timing system are ongoing for the LHC Run 3, with the goal of reaching an ultimate timing resolution better than 30 ps; they are also discussed here.
