Technical Design Report for the Upgrade of the ALICE Inner Tracking System

B Abelev Et Al,The Alice Collaboration

doi:10.1088/0954-3899/41/8/087002

B Abelev Et Al, The Alice Collaboration

Open Access

https://doi.org/10.1088/0954-3899/41/8/087002

Copy DOI

Abstract

ALICE (A Large Ion Collider Experiment) is studying the physics of strongly interacting matter, and in particular the properties of the Quark–Gluon Plasma (QGP), using proton–proton, proton–nucleus and nucleus–nucleus collisions at the CERN LHC (Large Hadron Collider). The ALICE Collaboration is preparing a major upgrade of the experimental apparatus, planned for installation in the second long LHC shutdown in the years 2018–2019. A key element of the ALICE upgrade is the construction of a new, ultra-light, high-resolution Inner Tracking System (ITS) based on monolithic CMOS pixel detectors. The primary focus of the ITS upgrade is on improving the performance for detection of heavy-flavour hadrons, and of thermal photons and low-mass di-electrons emitted by the QGP. With respect to the current detector, the new Inner Tracking System will significantly enhance the determination of the distance of closest approach to the primary vertex, the tracking efficiency at low transverse momenta, and the read-out rate capabilities. This will be obtained by seven concentric detector layers based on a 50 μm thick CMOS pixel sensor with a pixel pitch of about 30×30 μm2. This document, submitted to the LHCC (LHC experiments Committee) in September 2013, presents the design goals, a summary of the R&D activities, with focus on the technical implementation of the main detector components, and the projected detector and physics performance.

Highlights

ALICE (A Large Ion Collider Experiment) is designed to address the physics of strongly interacting matter, and in particular the properties of the Quark-Gluon Plasma (QGP), using proton–proton, proton–nucleus and nucleus–nucleus collisions at the CERN LHC.The ALICE apparatus consists of a central barrel, a forward muon spectrometer, and a set of small detectors for triggering and event characterisation
The increase in SNR can be substantial. These observations can qualitatively be described by looking at the depletion volume, which is larger when increasing the reverse voltage of the collection diode and when increasing the space towards the surrounding p-well
Results for 150 and 300 mW cm−2 power densities are reported for the baseline Stave cooling layout described in Sec. 4.2.1 and consisting of two pipes of 2.67 mm inner diameter each

Summary

Introduction

ALICE (A Large Ion Collider Experiment) is designed to address the physics of strongly interacting matter, and in particular the properties of the Quark-Gluon Plasma (QGP), using proton–proton, proton–nucleus and nucleus–nucleus collisions at the CERN LHC. The ALICE apparatus consists of a central barrel, a forward muon spectrometer, and a set of small detectors for triggering and event characterisation. The apparatus allows for a comprehensive study of hadrons, electrons, muons, photons and jets produced in heavyion collisions. The ALICE scientific plans and organisation for the approved programme are defined in the ALICE Physics Performance Report Vol I [1] (scientific programme) and Memorandum of Understanding [2] (the sharing of resources and responsibilities). An updated description of the ALICE detector can be found in [3]

Methods

Results

Conclusion