Entwicklung von Objekt orientierten C++ Algorithmen zur b-Quark Identifikation
type: CreativeWork
description: In the past thirty years particle physics has developed rapidly resulting in the formulation of the Standard Model, which seems to provide, at least in principle, a microscopic description for all known physical phenomena except gravity. The Standard Model is not complete, e.g. it lacks any explanation for the pattern of particle masses. The Higgs mechanism provides a solution to the problem of how particles acquire their masses. It implies the existence of at least one new particle, the Higgs boson H0, which has not yet been observed. The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) will be switched on in winter 2007. If the Higgs boson exists, the LHC will be able to detect it. Depending on the mass of the Higgs boson, physicists have a clear idea regarding its experimental signature. For quite low masses 50 < mH0 < 130 [GeV] the Higgs will predominantly decay into two b-quarks. The present study describes the investigation of the identification capability of b-quark signatures in the CMS experiment at the LHC. In order to test the b-quark identification methods developed, the data of the ALEPH experiment recorded at the LEP e+e- storage ring from 1992 till 1995 were used. The strategies developed for events from e+e- collisions recorded by the ALEPH experiment were applied to simulated pp events in the CMS detector. The new combined b-tag developed for ALEPH developed uses a combination of observables sensitive to the differences of b-hadron decays from other light quark hadron decays. The b-tag is based on the the ALEPH reconstruction algorithms for tracks and jets optimized for b-hadron identification. It is provided by the QIPBTAG tool of the ALEPH reconstruction tools library ALPHA. QIPBTAG also provides the calibrated resolution function obtained from the significance of the signed 3-dimensional impact parameter and used this to compute the track probabilities and the jet lifetime probability. The developed b-tag for A…
abstract: In the past thirty years particle physics has developed rapidly resulting in the formulation of the Standard Model, which seems to provide, at least in principle, a microscopic description for all known physical phenomena except gravity. The Standard Model is not complete, e.g. it lacks any explanation for the pattern of particle masses. The Higgs mechanism provides a solution to the problem of how particles acquire their masses. It implies the existence of at least one new particle, the Higgs boson H0, which has not yet been observed. The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) will be switched on in winter 2007. If the Higgs boson exists, the LHC will be able to detect it. Depending on the mass of the Higgs boson, physicists have a clear idea regarding its experimental signature. For quite low masses 50 < mH0 < 130 [GeV] the Higgs will predominantly decay into two b-quarks. The present study describes the investigation of the identification capability of b-quark signatures in the CMS experiment at the LHC. In order to test the b-quark identification methods developed, the data of the ALEPH experiment recorded at the LEP e+e- storage ring from 1992 till 1995 were used. The strategies developed for events from e+e- collisions recorded by the ALEPH experiment were applied to simulated pp events in the CMS detector. The new combined b-tag developed for ALEPH developed uses a combination of observables sensitive to the differences of b-hadron decays from other light quark hadron decays. The b-tag is based on the the ALEPH reconstruction algorithms for tracks and jets optimized for b-hadron identification. It is provided by the QIPBTAG tool of the ALEPH reconstruction tools library ALPHA. QIPBTAG also provides the calibrated resolution function obtained from the significance of the signed 3-dimensional impact parameter and used this to compute the track probabilities and the jet lifetime probability. The developed b-tag for A…
author: Heister, Arno
language: ger
keywords: info:eu-repo/classification/ddc/530, Higgs-Modell, Higgs-Teilchen, Higgs-Mechanismus, ALEPH <Teilchendetektor>, CMS-Detektor, LHC, b-Quark, LEP, Physik, b-Tag
date published: 2007
date modified: 2026-07-30T19:43:28Z
provider: RWTH Aachen University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Publikationsserver der RWTH Aachen University