Author: Biljana MitreskaPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Search for New Physics with an Angular Analysis of B0→D*μν Decays and Alignment of the LHCb Vertex Locator
Author: Biljana MitreskaSearching for New Physics in b → sl+l− Transitions at the LHCb Experiment
Author: Luca PescatorePublisher: Springer
ISBN: 3319664239
Category : Science
Languages : en
Pages : 204
Book Description
This thesis presents two analyses of semileptonic b → sl+l− decays using Flavour Changing Neutral Currents (FCNCs) to test for the presence of new physics and lepton flavour universality, and the equality of couplings for different leptons, which on the basis of experimental evidence is assumed to hold in the Standard Model, free from uncertainties as a result of knowledge of the hadronic matrix elements. It also includes the angular analysis of Lambda_b->Lambda mumu decay and the RK* measurement, both of which are first measurements, not yet performed by any other experiment.
Search for New Physics in an Angular Analysis of the B+→K*+μ+μ− Decay at LHCb
Author: David GerickAlignment of the LHCb Vertex Locator and Lifetime Measurements of Two-body Hadronic Final States
Author: Marco GersabeckPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Lifetime measurements offer excellent opportunities for precision tests of the Standard Model of Particle Physics as well as for discovery of effects involving particles beyond the Standard Model. This thesis presents a method for measurements of lifetimes and lifetime ratios and its application to two-body hadronic final states of heavy flavour decays at LHCb. The LHCb experiment is designed to measure heavy flavour particle decays produced in proton-proton collisions at the LHC. Key to high quality vertexing is the spatial alignment of the Vertex Locator. The algorithms designed for this task, including a novel approach for the relative sensor alignment, are discussed in detail. Their performance is presented using test beam data as well as data using the first beam induced tracks from LHC. The precision of these algorithms is found to be of the order of 1-2 microns. A method for lifetime fitting using a Monte Carlo independent approach to determine a lifetime acceptance function on an event-by-event basis is presented. These acceptance functions are crucial to account for a bias caused by the trigger selection. The un-binned maximum likelihood fitter based on this method does not rely on a parametrised model for the lifetime distribution of combinatorial background. The fit of the lifetime measured in Bs->K+K- decays using a simulated data sample equivalent to an integrated luminosity of 0.1/fb would yield tau(Bs->K+K- ) = (1.498+/-0.030(stat.)+/-0.005(syst.))ps with an average input lifetime of 1.500ps. A competitive measurement of DeltaGamma_s extracted from the Bs->K+K- lifetime measurement would require a data set equivalent to about 0.7/fb of luminosity. With an integrated luminosity of only about 0.03/fb it will be possible to make a competitive measurement of the D mixing parameter y_CP. This uses a lifetime ratio measurement with prompt D->h+h - decays. A first event selection for prompt D->h+h - decays is presented. The major hurdle for this measurement is the contribution from secondary D decays. Possible solutions are discussed.
First Observation of Fully Reconstructed B0 and Bs0 Decays into Final States Involving an Excited Neutral Charm Meson in LHCb
Author: Arnau Brossa GonzaloPublisher: Springer Nature
ISBN: 3031227530
Category : Science
Languages : en
Pages : 241
Book Description
This book presents the latest results on the branching fraction and phase space distribution of B0 and Bs0 decays into final states including excited neutral charm mesons. This work represents four years of research, and the book describes in detail all the necessary steps and techniques required to perform a physics analysis of the data recorded by the LHCb experiment in the years 2016–2018. Although the results presented in this book represent the first measurement of such decays, the text is written in a manner accessible to Ph.D. students and early career researchers. Thus, all the contents included in this book are described in a pedagogical way, including technical details that would allow the results to be reproduced in future. In addition to the methodology used to perform these measurements, the book also includes a description of the theoretical background required to interpret the results presented, as well as a technical description of the LHCb detector, which provided the data sample used in this study.
Development of the Lhcb Vertex Locator Readout Electronics
Author: Iouri ErmolinePublisher: LAP Lambert Academic Publishing
ISBN: 9783659129445
Category :
Languages : en
Pages : 108
Book Description
The LHCb experiment is built at the LHC collider at CERN. It is a forward single-arm spectrometer dedicated to precision measurements of CP violation and rare decays in the b quark sector. In the Standard Model, CP violation arises via the complex phase of the 3 x 3 CKM (Cabibbo-Kobayashi-Maskawa) quark mixing matrix. The LHCb experiment will test the unitarity of this matrix by measuring in several theoretically unrelated ways all angles and sides of the so-called "unitary triangle". This will allow to over-constrain the model and - hopefully - to exhibit inconsistencies which will be a signal of physics beyond the Standard Model. The Vertex reconstruction is a fundamental requirement for the LHCb experiment. Displaced secondary vertices are a distinctive feature of b-hadron decays. This signature is used in the LHCb topology trigger. The Vertex Locator (VeLo) has to provide precise measurements of track coordinates close to the interaction region. These are used to reconstruct production and decay vertices of beauty-hadrons and to provide accurate measurements of their decay lifetimes. The VeLo electronics was designed in parallel with the silicon detector development.
Study of Double Charm B Decays with the LHCb Experiment at CERN and Track Reconstruction for the LHCb Upgrade
Author: Renato QuaglianiPublisher: Springer
ISBN: 3030018393
Category : Science
Languages : en
Pages : 277
Book Description
This book discusses the study of double charm B decays and the first observation of B0->D0D0Kst0 decay using Run I data from the LHCb experiment. It also describes in detail the upgrade for the Run III of the LHCb tracking system and the trigger and tracking strategy for the LHCb upgrade, as well as the development and performance studies of a novel standalone tracking algorithm for the scintillating fibre tracker that will be used for the LHCb upgrade. This algorithm alone allows the LHCb upgrade physics program to achieve incredibly high sensitivity to decays containing long-lived particles as final states as well as to boost the physics capabilities for the reconstruction of low momentum particles.
Angular Analysis of B0 -> K*0e+e- Decays at LHCb
Author: Zhenzi WangStudies of CP-Violation in Charmless Three-Body b-Hadron Decays
Author: Daniel O'HanlonPublisher: Springer
ISBN: 3030022064
Category : Science
Languages : en
Pages : 225
Book Description
This book highlights two essential analyses of data collected during the LHCb experiment, based on the Large Hadron Collider at CERN. The first comprises the first observation and studies of matter-antimatter asymmetries in two three-body b-baryon decays, paving the way for more precise measurements of the relatively unknown decay properties of b-baryon decays. The second is an analysis of a charged B meson decay to three charged pions, where previously large matter-antimatter asymmetries were observed in a model-independent analysis. Here a model of the decay amplitude is constructed using the unitarity-conserving ‘K-matrix’ model for the scalar contributions, so as to gain an understanding of how the previously observed matter-antimatter asymmetries arise; further, the model’s construction yields the most precise and comprehensive study of this decay mode to date.
Angles and B-mons
Author: Aleksandra SnochPublisher:
ISBN: 9789464961881
Category :
Languages : en
Pages : 0
Book Description