The upgrade of the ALICE TPC with GEMs and continuous readout

Abstract

The upgrade of the ALICE TPC will allow the experiment to cope with the high interaction rates foreseen for the forthcoming Run 3 and Run 4 at the CERN LHC. In this article, we describe the design of new readout chambers and front-end electronics, which are driven by the goals of the experiment. Gas Electron Multiplier (GEM) detectors arranged in stacks containing four GEMs each, and continuous readout electronics based on the SAMPA chip, an ALICE development, are replacing the previous elements. The construction of these new elements, together with their associated quality control procedures, is explained in detail. Finally, the readout chamber and front-end electronics cards replacement, together with the commissioning of the detector prior to installation in the experimental cavern, are presented. After a nine-year period of R&D, construction, and assembly, the upgrade of the TPC was completed in 2020.

arXiv comment88 pages, 60 figures

References in corpus (16)

• Performance of the ALICE Experiment at the CERN LHC
• The ALICE TPC, a large 3-dimensional tracking device with fast readout for ultra-high multiplicity events
• Progress on large area GEMs (VCI 2010)
• Charge density as a driving factor of discharge formation in GEM-based detectors
• Layout and Assembly Technique of the GEM Chambers for the Upgrade of the CMS First Muon Endcap Station
• Optical quality assurance of GEM foils
• Particle identification studies with a full-size 4-GEM prototype for the ALICE TPC upgrade
• A Large Ungated TPC with GEM Amplification
• Ion mobility measurements in Ar-CO${}_2$, Ne-CO${}_2$, and Ne-CO${}_2$-N${}_2$ mixtures, and the effect of water contents
• Secondary discharge studies in single and multi GEM structures
• Measurements of the Charging-Up Effect in Gas Electron Multipliers
• Measurements of ion mobility in argon and neon based gas mixtures
• Building a large-area GEM-based readout chamber for the upgrade of the ALICE TPC
• High voltage scheme optimization for secondary discharge mitigation in GEM-based detectors
• GEM Foil Quality Assurance For The ALICE TPC Upgrade
• Discharge probability studies with multi-GEM detectors for the ALICE TPC Upgrade

Cited by in corpus (12)

• ALICE upgrades during the LHC Long Shutdown 2
• Upgrade of the ALICE ITS detector
• Track Reconstruction in a High-Density Environment with ALICE
• The HIBEAM Instrument at the European Spallation Source
• The sPHENIX Micromegas Outer Tracker
• Discharge mitigation methods in MPGD-based detectors
• Reduction of ion back flow using a quadruple GEM detector with various gas mixtures
• New (TH)GEM coating materials characterised using spectroscopy methods
• Evidence for polyimide redeposition and possible correlation with sparks in Gas Electron Multipliers working in CF${}_4$ mixtures
• Observation on the bias current variation of a single mask triple GEM chamber
• Comparative study on charging-up of single, double and triple Gas Electron Multipliers (GEM)
• Impact of trace amounts of water on the stability of Micro-Pattern Gaseous Detectors measured in Ar-CO${}_2$ (90-10)