Model-Independent Measurement of the CKM Angle y in B± [h+h-pi+pi-]Dh'±(h=K,pi) Decays at LHCb and BESIIII

This book presents a striking demonstration of the synergies that exist between particle-physics experiments. A measurement is reported of the weak-phase , which is a fundamental parameter of the Standard Model and can be regarded as quantifying the amount of CP violation that is allowed by the theory. The parameter is measured through a determination of b-meson decays collected by the LHCb experiment at CERN. The b-mesons are reconstructed in a decay to a charm meson and a pion or a kaon, and the charm meson is itself reconstructed in one of two four-body final states (KK or ). This is the first time these decay modes have been used in a measurement, which is itself a notable achievement of the thesis study. In order to interpret the measured observables in a theoretically clean manner, it is necessary to have knowledge of the dynamics of the charm-hadron decays. This knowledge is obtained from a study of charm-meson pair production in e+e- collisions at the psi(3770) resonance, using data collected by the BESIII experiment in Beijing. The quantum-correlations present in these decays give unique access to the required information, which is then imported back into the LHCb measurement. The precision obtained on is competitive with the most sensitive individual measurements so far performed of this parameter in other decay modes.

Nominated as an outstanding thesis by Oxford University Presents a striking demonstration of the synergies that exist between particle and physics experiments Features a measurement of the weak-phase gamma, which is a fundamental parameter of the standard model

Autorentext

Martin Duy Tat obtained his PhD from University of Oxford, working for the LHCb and BESIII experiments, and currently he is the postdoctoral researcher at Heidelberg University working for the LHCb experiment.

Inhalt

Introduction.- Theoretical background.- Optimised binning scheme for D0 K+K+.- The BESIII detector .- Selection of single- and double-tag events.- Measurement of strong-phase differences.- The LHCb detector.- Selection of B± [K+K+]Dh± and [++]Dh± events.- Model-independent measurement of .- Summary and outlook.