Design and development of vertex reconstruction for CMS analysis Studies of micro strips gas chambers (MSGC) and micro strips silicium detectors

• Main Author: Moreau, Stéphanie
• Other Authors: Département Recherches Subatomiques (DRS-IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Université Louis Pasteur - Strasbourg I, Jean-Marie Brom([e-mail])
• Format: Doctoral or Postdoctoral Thesis
• Language: French
• Published: HAL CCSD 2002
• Subjects: sans; [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]; Orca
• Online Access: https://tel.archives-ouvertes.fr/tel-00392517; https://tel.archives-ouvertes.fr/tel-00392517/document; https://tel.archives-ouvertes.fr/tel-00392517/file/these.pdf

The work presented in this thesis has contributed to the development of the Compact Muon Solenoid detector (CMS) that will be installed at the future Large Hadron Collider (LHC) which will start running in summer 2007. This report is organised in three parts : the study of gaseous detectors and silicon microstrips detectors, and a development of a software for the reconstruction and analysis of CMS data in the framework of ORCA. First, the microstrips gaseous detectors (MSGC) study was on the ultimate critical irradiation test before their substitution in the CMS tracker. This test showed a really small number of lost anodes and a stable signal to noise ratio. This test proved that the described MSGC fulfil all the requirements to be integrated in the CMS tracker. The following contribution described a study of silicon microstrips detectors and its electronics exposed to a 40 MHz bunched LHC like beam. These tests indicated a good behaviour of the data acquisition and control system. The signal to noise ratio, the bunch crossing identification and the cluster finding efficiency had also be analysed. The last study concern the design and the development of an ORCA algorithm dedicates to secondary vertex reconstruction. This iterative algorithm aims to be use for b tagging. This part analyse also primary vertex reconstruction in events without and with pile up. Les études présentées dans cette thèse ont contribuées au développement du détecteur CMS (Compact Muon Solenoid) auprès du futur cllisionneur LHC (Large Hadron Collider) dont la mise en service est prévue pour l'été 2007. Cette thèse se décompose en trois études qui portent respectivement sur l'étude de détecteurs gazeux à micropistes, l'étude de détecteurs silicium à micropistes ainsi que sur O.R.C.A., le logiciel de reconstruction et d'analyse des données du détecteur CMS. L'étude des détecteurs gazeux à micropistes (MSGC) a porté sur les derniers tests sous un faisceau de haute intensité avant leur remplacement dans le trajectographe de CMS. Ces tests ...