Beam Coupling Impedance Measurement and Mitigation for a TOTEM Roman Pot

RF Measurements of the New TOTEM Roman Pot

The TOTEM experiment has been designed to measure the total proton-proton cross section and to study the elastic and diffractive scattering at the LHC energy. The measurement requires detecting protons at distances as small as 1 mm from the beam center: TOTEM uses Roman Pots, movable beam pipe insertions, hosting silicon detectors. In the first period of LHC operation no relevant problems were detected with Roman Pots retracted or inserted during special runs. However, when operating the LHC with high intensity beams, impedance induced heating has been observed during the Roman Pots insertion.…

Tests of a Roman Pot Prototype for the TOTEM Experiment

The TOTEM collaboration has developed and tested the first prototype of its Roman Pots to be operated in the LHC. TOTEM Roman Pots contain stacks of 10 silicon detectors with strips oriented in two orthogonal directions. To measure proton scattering angles of a few microradians, the detectors will approach the beam centre to a distance of 10 sigma + 0.5 mm (= 1.3 mm). Dead space near the detector edge is minimised by using two novel "edgeless" detector technologies. The silicon detectors are used both for precise track reconstruction and for triggering. The first full-sized prototypes of both …

The First 1 1/2 Years of TOTEM Roman Pot Operation at LHC

Since the LHC running season 2010, the TOTEM Roman Pots (RPs) are fully operational and serve for collecting elastic and diffractive proton-proton scattering data. Like for other moveable devices approaching the high intensity LHC beams, a reliable and precise control of the RP position is critical to machine protection. After a review of the RP movement control and position interlock system, the crucial task of alignment will be discussed.

利用TOTEM Roman pot探测器对高-$β^*$ LHC数据进行质子重建

Proton reconstruction with the TOTEM Roman pot detectors for high-$β^*$ LHC data

本文针对2018年13 TeV高-$β^*$ LHC数据，提出基于公共多边形区域的TOTEM Roman pot质子径迹重建与微米级准直方法，并测量条带探测效率，为中心专有物理分析提供优化重建工具。

Edgeless Silicon Detectors for the TOTEM Experiment

Silicon detectors for the Roman Pots of the large hadron collider TOTEM experiment aim for full sensitivity at the edge where a terminating structure is required for electrical stability. This work provides an innovative approach reducing the conventional width of the terminating structure to less than 100 microns, still using standard planar fabrication technology. The objective of this new development is to decouple the electric behaviour of the surface from the sensitive volume within tens of microns. The explanation of the basic principle of this new approach together with the experimental…

Project to install roman pot detectors at 220 m in ATLAS

We give a short description of the project to install roman pot detectors at 220 m from the interaction point in ATLAS. This project is dedicated to hard diffractive measurements at high luminosity.