Deep neural network techniques in the calibration of space-charge distortion fluctuations for the ALICE TPC

19 May 2021, 11:16
13m
Short Talk Offline Computing Artificial Intelligence

Speaker

Ernst Hellbar (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE))

Description

The Time Projection Chamber (TPC) of the ALICE experiment at the CERN LHC was upgraded for Run 3 and Run 4. Readout chambers based on Gas Electron Multiplier (GEM) technology and a new readout scheme allow continuous data taking at the highest interaction rates expected in Pb-Pb collisions. Due to the absence of a gating grid system, a significant amount of ions created in the multiplication region is expected to enter the TPC drift volume and distort the uniform electric field that guides the electrons to the readout pads. Analytical calculations were considered to correct for space-charge distortion fluctuations but they proved to be too slow for the calibration and reconstruction workflow in Run 3. In this paper, we discuss a novel strategy developed by the ALICE Collaboration to perform distortion-fluctuation corrections with machine learning and convolutional neural network techniques. The results of preliminary studies are shown and the prospects for further development and optimization are also discussed.

Primary authors

Sergey Gorbunov (Goethe University Frankfurt (DE)) Ernst Hellbar (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE)) Gian Michele Innocenti (CERN) Marian Ivanov (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE)) Maja Jadwiga Kabus (Warsaw University of Technology (PL)) Matthias Kleiner (Goethe University Frankfurt (DE)) Haris Riaz (National University of Sciences & Technology (NUST), Islamabad) David Rohr (CERN) Rifki Sadikin (Indonesian Institute of Sciences (ID)) Kai Schweda (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE)) Daiki Sekihata (University of Tokyo (JP)) Ruben Shahoyan (CERN) Benedikt Volkel (Ruprecht Karls Universitaet Heidelberg (DE)) Jens Wiechula (Goethe University Frankfurt (DE)) Chiara Zampolli (CERN) Harald Appelshaeuser (Goethe University Frankfurt (DE)) Henner Buesching (Goethe University Frankfurt (DE)) Lukasz Kamil Graczykowski (Warsaw University of Technology (PL)) Jan Fiete Grosse-Oetringhaus (CERN) Peter Hristov (CERN) Taku Gunji (University of Tokyo (JP)) Silvia Masciocchi (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE))

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