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Measurement of the J/ Elliptic Flow in Pb-Pb Collisions at Snn=5.02Tev

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Measurement of the J/ Elliptic Flow in Pb-Pb Collisions at Snn=5.02Tev Measurement of the J/ elliptic flow in Pb-Pb collisions p at sNN=5.02TeV with the muon spectrometer of ALICE at the LHC Audrey Francisco To cite this version: p Audrey Francisco. Measurement of the J/ elliptic flow in Pb-Pb collisions at sNN=5.02TeV with the muon spectrometer of ALICE at the LHC. High Energy Physics - Experiment [hep-ex]. Ecole nationale supérieure Mines-Télécom Atlantique, 2018. English. NNT : 2018IMTA0087. tel-02010296 HAL Id: tel-02010296 https://tel.archives-ouvertes.fr/tel-02010296 Submitted on 7 Feb 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. THESE DE DOCTORAT DE L’ÉCOLE NATIONALE SUPERIEURE MINES-TELECOM ATLANTIQUE BRETAGNE PAYS DE LA LOIRE - IMT ATLANTIQUE COMUE UNIVERSITE BRETAGNE LOIRE ECOLE DOCTORALE N° 596 Matière, Molécules, Matériaux Spécialité : Physique Subatomique et Instrumentation Nucléaire Par Audrey FRANCISCO Measurement of the J/� elliptic flow in Pb-Pb collisions at √sNN=5.02TeV with the muon spectrometer of ALICE at the LHC Thèse présentée et soutenue à Nantes le 24 Septembre 2018 Unité de recherche : SUBATECH— UMR6457 Thèse N° : 2018IMTA0087 Composition du Jury : Président : Pol-Bernard GOSSIAUX Professeur, IMT-Atlantique Examinateurs : Javier CASTILLO CASTELLANOS Chercheur-Ingénieur, CEA Manuel CALDERON DE LA BARÇA SANCHEZ Professeur, University of California Davis Marielle CHARTIER Professeur, University of Liverpool Silvia NICCOLAI Directeur de Recherche CNRS, Univ. Paris-Sud/Paris-Saclay Dir. de thèse : Gines MARTINEZ GARCIA Directeur de Recherche CNRS, SUBATECH Co-dir. de thèse : Laurent APHECETCHE Chargé de Recherche CNRS, SUBATECH Guillaume BATIGNE Maître-Assistant, IMT-Atlantique 2 Remerciements “There’s nothing you can do that can’t be done / Nothing you can sing that can’t be sung / Nothing you can say, but you can learn how to play the game / It’s easy / All you need is love.” — John Lennon, Magical Mystery Tour (The Beatles) Cette page est dédiée à tous ceux qui ont croisé mon chemin. Merci pour votre aide, votre confiance, vos encouragements, vos conseils, votre temps et votre inspiration. Mes pensées s’orientent vers mes proches. Par pudeur et par souci de concision, je ne m’adresserai pas individuellement à chacun d’entre vous mais soyez assurés de ma re- connaissance. Je citerai ici mon cher directeur de thèse, l’ensemble du groupe plasma, le laboratoire Subatech, notamment les services administratifs et informatiques, les mem- bres de la collaboration ALICE, plus spécialement le groupe PWG-DQ et les équipes des upgrades ITS et MFT, et enfin mon jury de thèse, pour cette tâche chronophage. Merci également à tous les yeux qui ont brillé en m’écoutant. Enfin, merci à ceux qui ont renforcé ma détermination par leurs douces objurgations et lassitudes, vous ne mesurerez jamais l’importance de votre contribution. Je souligne aussi le soutien et l’acceuil de la région Pays de la Loire, du CNRS, de l’IMT Atlantique, du laboratoire Subatech, de l’Université Bretagne-Loire, de la collaboration ALICE et du CERN qui ont permis la réalisation de cette thèse. Jean-Baptiste Matthew Papi Camille Mima Noa Zaz Manue Pierre Gines Maman Rossella Sophie Ledieudeville Anne ClémentPapa Françoise Julien George Nicole Toto Schmitt Nico ChristopheSarahAndry Mamie Aurélie Przemyslaw Abdou Pierrick Sandrine Maxime Barbara Julien Reynaud Louis Elisa Emilia Mathilde Roberta Michelle Laure Grégou Jourdain Lydie Stephane Karine Fifi Daniel Thorey Frédéric Manon Avó Magnani Devaux Maria Isabelle Martin D&L Tanja Silvia Saleres Frédéric Stéphanie Javier Laurent Avril Kausch Paolo Joël Tonio Houdart Alberto Mélanie Evan Luciano Erwann Anouk Barbary Cyrille Alexandru Laura Borgazzi Alexandre Ophélie Iuri Patrick Petit Dominique Florian Sarah Joy Okja Farah Hugo Lourdes Felicite Pol Arnaud Agnes Sami Sautier Jean-Michel Antoine Zerrouk Mout Dom Mehdi ChristineJérémy Christa Henry Christophe JurgenCristina Rosita Josiane Clément Doudou Jerome Barbara Marie Pion Léa Jacqueline Sélim Cholvy Khalil FB GiulianettiMartinet Pascaline Cvetan Cynthia Philippe Steinmetz Lucile Tchedry Sonia Alice Lili Sophie Brigitte Anton Javier Akim MonikaJana Charles Séverine Zaida Guillaume Guy PoussyGervilliers Torsten Jacopo David Sary Diego Momo Chantal Aubert Pierre Felix Hyeonjoong Urbain Massimiliano Ionut Belda Delphine Manuel Astrid Hadi Marielle Philippe Ahmed Pichon Gabriel Boris Manuel Gosssaert Nadège Roy Benjamin Crémilde Sylvia Stefano À l’attention de mon entourage non-physicien : Le terme « gypsy » ou « gipsy » est un mot anglais souvent désigné sous le terme de « gens du voyage » en France. Il fait généralement référence à une communauté d’individus dont le mode de vie a une origine nomade, bien que beaucoup soient aujourd’hui sédentaires. Le terme englobe plusieurs populations d’origines éthniques et de cultures différentes. Cette thèse ne raconte pas leur histoire. 3 4 I NTRODUCTION Significant investments have been made to study the properties of the strong interaction, responsible for the stability of nuclei. Several experimental facilities and experiments have been devoted to the creation and observation of a deconfined state of matter, the Quark Gluon Plasma (QGP), where elementary building blocks of nuclei evolve quasi-freely. Heavy-ion collisions are unique tool to investigate this primordial state of the Universe and test Quantum ChromoDynamics (QCD) predictions. The A Large Ion Colliding Experiment (ALICE) experiment is a dedicated apparatus at the Large Hadron Collider (LHC). The lifetime of the created QGP is very short ( 5–10 fm/c) and makes it impossible ∼ to observe it directly. Various observables are therefore measured to extract information about the deconfined state. Among them, anisotropic flow provides very useful results to extract the thermal properties of the system. Bound states of heavy quarks have been identified as ideal probes of the ALICE several decades ago. This thesis contains two parts: the measurement of the J/ψ elliptic flow in Pb–Pb collisions at psNN = 5.02TeV with the ALICE detector and the characterisation of CMOS sensors for the Muon Forward Tracker upgrade. The first chapter of this thesis of offers a general introduction to the Quark-Gluon Plasma and its study through heavy-ion collisions. The second chapter describes the ALICE detector, dedicated to heavy-ion collision studies, and its future upgrade with details on the Muon Forward Tracker and the work performed for the characterisation study of the sensors. Chapter three is an overview of collective phenomena in the QGP with a summary of the main observations from A–A collisions, a brief discussion of the small- system results and a dedicated section on heavy flavours. The relevance of quarkonium states in the study of A–A collisions is discussed in chapter four. Experimental results and theoretical description of heavy-quark bound states are presented. The analysis performed during this thesis is detailed in the chapter 5. The J/ψ elliptic flow analysis was performed at forward rapidity in Pb–Pb collisions at psNN = 5.02TeV through the dimuon decay channel. The measurement was performed using the Event Plane method (using either the v or the dN/d∆φ technique) and the Scalar Product method. The azimuthal 〈 2 〉 dependence of J/ψ production is also investigated here for the first time. The results are discussed in the chapter 6 by comparing it to other measurements and theoretical predictions (when available) and drawing the conclusions about charm-quark flow at LHC. Future prospectives with the ALICE detector upgrade are also proposed here. The last chapter is a general conclusion over quarkonium results and the results obtained during this thesis. i ii C ONTENTS Contents iii 1 Introduction to the Quark-Gluon Plasma 3 1.1 A deconfined state of matter . 3 1.1.1 Quantum ChromoDynamics . 3 1.1.2 The phase transition . 4 1.2 Heavy-ion collisions . 5 1.2.1 The Bjorken scenario . 6 1.2.2 Experimental signatures of the QGP . 7 2 Studying experimentally the QGP with ALICE 9 2.1 The LHC collider . 9 2.2 The ALICE detector . 11 2.2.1 The Inner Tracking System (ITS) . 11 2.2.2 Zero Degree Calorimeter (ZDC) . 11 2.2.3 The VZERO (V0) . 12 2.2.4 The TZERO (T0) . 12 2.2.5 The Time Projection Chamber (TPC) . 12 2.2.6 The muon arm . 12 2.2.7 Triggering System and Data Acquisition . 14 2.3 The Muon Forward Tracker upgrade . 16 2.3.1 Physics motivations . 16 2.3.2 Overview of the detector . 17 2.4 CMOS prototype characterisation . 22 2.4.1 Measurement techniques . 22 2.4.2 ALPIDE prototypes . 25 3 Elliptic flow 29 3.1 Azimuthal asymmetry . 29 3.2 Observations in A–A collisions . 30 3.3 Heavy-flavour results . 34 3.4 Collectivity in small systems . 39 4 Bound states of heavy quarks as a probe of the QGP 43 4.1 Relevance of heavy quarks in the QGP study . 43 4.2 Charmonium production . 44 4.2.1 Spectroscopy . 44 4.2.2 pp collisions: stringent pQCD test and A–A reference . 45 4.3 Charmonium production in heavy ion collisions: probing the QGP . 45 iii CONTENTS 4.3.1 Cold nuclear matter effects . 46 4.3.2 Hot medium effects . 46 4.4 Charmonium elliptic flow . 53 4.4.1 RHIC results . 53 4.4.2 LHC results at psNN = 2.76TeV . 54 4.5 Theoretical models . 59 5 Analysis 61 5.1 Azimuthal asymmetry analysis . 61 5.1.1 Dectector equalisation . 62 5.1.2 Event selection and implementation .
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