Performance and operation experience of the ATLAS Semiconductor Tracker

Zhijun Liang,(On Behalf Of The Atlas Collaboration)

doi:10.1142/s2010194514602956

Abstract

We report on the operation and performance of the ATLAS Semi-Conductor Tracker (SCT), which has been functioning for 3 years in the high luminosity, high radiation environment of the Large Hadron Collider at CERN. We also report on the few improvements of the SCT foreseen for the high energy run of the LHC. We find 99.3% of the SCT modules are operational, the noise occupancy and hit efficiency exceed the design specifications; the alignment is very close to the ideal to allow on-line track reconstruction and invariant mass determination. We will report on the operation and performance of the detector including an overview of the issues encountered. We observe a significant increase in leakage currents from bulk damage due to non-ionizing radiation and make comparisons with the predictions.

Highlights

The ATLAS detector[1] is a multi-purpose apparatus designed to study a wide range of physics processes at the Large Hadron Collider (LHC) at CERN
The recent observation of a Higgs-like particle reported by the ATLAS and CMS collaborations is a milestone in particle physics history.[2, 3]
The semiconductor tracker (SCT) was installed into ATLAS, and was ready for the first LHC proton-proton collisions at a centre of mass energy of 7GeV in March 2010

Summary

Introduction

The ATLAS detector[1] is a multi-purpose apparatus designed to study a wide range of physics processes at the Large Hadron Collider (LHC) at CERN. The semiconductor tracker (SCT) is a precision silicon microstrip detector which forms an integral part of this tracking system. The SCT is constructed of 4088 silicon detector modules,[4, 5] for a total of 6.3 million strips. The SCT silicon micro-strip sensors[6] are processed in the planar p-in-n technology. The signals are processed in the front-end ABCD3T ASICs,[7] which use a binary readout architecture. Data is transferred to the off-detector readout electronics via optical fibres. This is an Open Access article published by World Scientific Publishing Company. Further distribution of this work is permitted, provided the original work is properly cited

Detector Operations

Hit Efficiency

Findings

Radiation Damage