Track Reconstruction in a High-Density Environment with ALICE

TL;DR

This paper details the methods used by ALICE at CERN to accurately reconstruct particle tracks in the high-density environment of heavy-ion collisions, addressing challenges like space charge distortions with specialized software solutions.

Contribution

It introduces novel solutions and software tools for overcoming baseline fluctuations and space charge distortions in TPC track reconstruction during LHC Run 2.

Findings

Effective correction of space charge distortions achieved

Enhanced track reconstruction accuracy in high-density environments

Successful implementation of software tools for real-time data processing

Abstract

ALICE is the dedicated heavy-ion experiment at the CERN Large Hadron Collider (LHC). Its main tracking and particle-identification detector is a large volume Time Projection Chamber (TPC). The TPC has been designed to perform well in the high-track density environment created in high-energy heavy-ion collisions. In this proceeding, we describe the track reconstruction procedure in ALICE. In particular, we focus on the two main challenges that were faced during the Run 2 data-taking period (2015--2018) of the LHC, which were the baseline fluctuations and the local space charge distortions in the TPC. We present the corresponding solutions in detail and describe the software tools that allowed us to circumvent these challenges.