Gas Electron Multipliers for the Antiproton Decelerator

TL;DR

This paper introduces a lightweight Gas Electron Multiplier (GEM) detector for precise, non-intrusive beam profile measurements at CERN's Antiproton Decelerator, overcoming limitations of previous multi-wire chambers.

Contribution

The paper presents a novel GEM-based detector with 2D readout for beam profiling, offering improved accuracy and reduced beam disturbance compared to traditional methods.

Findings

Successful installation and testing of the prototype in 2010

Deployment of five detectors in beam lines for ongoing experiments

Enhanced beam profile measurement capabilities at CERN

Abstract

The new beam profile measurement for the Antiproton Decelerator (AD) at CERN is based on a single Gas Electron Multiplier (GEM) with a 2D readout structure. This detector is very light (~0.4% X0), and measures horizontal and vertical profiles directly in one plane. This overcomes the problems previously encountered with multi-wire proportional chambers for the same purpose, where beam interactions with the detector severely affect the obtained profiles. A prototype was installed and successfully tested in late 2010, with another five detectors now installed in the ASACUSA and AEGIS beam lines. This paper will provide a detailed description of the detector and discuss the results obtained.