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Angular Analysis of the decay $B^0 \to \phi K^*(892)^0$

The LHCb experiment is a single-arm forward spectrometer situated at the Large Hadron Collider, CERN. LHCb is optimised for the precision study of beauty and charm flavoured hadrons and in 2011 collected 1 fb$^{-1}$ of proton-proton collision data at a centre-of-mass energy of 7 TeV. The aim of LHC...

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Autor principal: Lambert, Dean Michael
Lenguaje:eng
Publicado: 2016
Materias:
Acceso en línea:http://cds.cern.ch/record/2140465
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author Lambert, Dean Michael
author_facet Lambert, Dean Michael
author_sort Lambert, Dean Michael
collection CERN
description The LHCb experiment is a single-arm forward spectrometer situated at the Large Hadron Collider, CERN. LHCb is optimised for the precision study of beauty and charm flavoured hadrons and in 2011 collected 1 fb$^{-1}$ of proton-proton collision data at a centre-of-mass energy of 7 TeV. The aim of LHCb is to search for rare decays and make precise measurements of Charge-Parity $(\textit{CP})$ violation in the beauty and charm sectors. In the Standard Model the decay $B^0 \to \phi K^*(892)^0$ is described by a loop mediated process, providing a sensitive test for new physics. In this decay, signs of $\textit{CP}$ violation could indicate the presence of physics beyond the Standard Model. This thesis presents a study of the flavour eigenstate $B^0 \to \phi(\to K^+K^-) K^*(892)^0(\to K^+\pi^-)$ and its charge conjugate $\overline{B}^0$-decay. The decay products form an admixture of $\textit{CP}$-even and $\textit{CP}$-odd eigenstates, which can have longitudinal or transverse polarisation. An angular analysis is performed to disentangle these different contributions and the polarisation amplitudes and strong phases are measured. No difference is observed between $B^0$ and $\overline{B}{^0}$ amplitudes, supporting the hypothesis that $\textit{CP}$ is conserved in this decay. In addition, the Triple Product Asymmetries (TPAs) are determined from the products of the polarisation amplitudes and strong phases. $\textit{True}$ TPAs are zero in the event that $\textit{CP}$ symmetry is conserved, while $\textit{fake}$ TPAs can arise due to final-state interactions. Although the measured true TPAs are consistent with zero, several significant fake TPAs are observed.
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spelling cern-21404652019-09-30T06:29:59Zhttp://cds.cern.ch/record/2140465engLambert, Dean MichaelAngular Analysis of the decay $B^0 \to \phi K^*(892)^0$Particle Physics - ExperimentThe LHCb experiment is a single-arm forward spectrometer situated at the Large Hadron Collider, CERN. LHCb is optimised for the precision study of beauty and charm flavoured hadrons and in 2011 collected 1 fb$^{-1}$ of proton-proton collision data at a centre-of-mass energy of 7 TeV. The aim of LHCb is to search for rare decays and make precise measurements of Charge-Parity $(\textit{CP})$ violation in the beauty and charm sectors. In the Standard Model the decay $B^0 \to \phi K^*(892)^0$ is described by a loop mediated process, providing a sensitive test for new physics. In this decay, signs of $\textit{CP}$ violation could indicate the presence of physics beyond the Standard Model. This thesis presents a study of the flavour eigenstate $B^0 \to \phi(\to K^+K^-) K^*(892)^0(\to K^+\pi^-)$ and its charge conjugate $\overline{B}^0$-decay. The decay products form an admixture of $\textit{CP}$-even and $\textit{CP}$-odd eigenstates, which can have longitudinal or transverse polarisation. An angular analysis is performed to disentangle these different contributions and the polarisation amplitudes and strong phases are measured. No difference is observed between $B^0$ and $\overline{B}{^0}$ amplitudes, supporting the hypothesis that $\textit{CP}$ is conserved in this decay. In addition, the Triple Product Asymmetries (TPAs) are determined from the products of the polarisation amplitudes and strong phases. $\textit{True}$ TPAs are zero in the event that $\textit{CP}$ symmetry is conserved, while $\textit{fake}$ TPAs can arise due to final-state interactions. Although the measured true TPAs are consistent with zero, several significant fake TPAs are observed.CERN-THESIS-2014-368oai:cds.cern.ch:21404652016-03-21T09:41:21Z
spellingShingle Particle Physics - Experiment
Lambert, Dean Michael
Angular Analysis of the decay $B^0 \to \phi K^*(892)^0$
title Angular Analysis of the decay $B^0 \to \phi K^*(892)^0$
title_full Angular Analysis of the decay $B^0 \to \phi K^*(892)^0$
title_fullStr Angular Analysis of the decay $B^0 \to \phi K^*(892)^0$
title_full_unstemmed Angular Analysis of the decay $B^0 \to \phi K^*(892)^0$
title_short Angular Analysis of the decay $B^0 \to \phi K^*(892)^0$
title_sort angular analysis of the decay $b^0 \to \phi k^*(892)^0$
topic Particle Physics - Experiment
url http://cds.cern.ch/record/2140465
work_keys_str_mv AT lambertdeanmichael angularanalysisofthedecayb0tophik8920