This is the first advanced, systematic and comprehensive look at weak decays in the framework of gauge theories. Included is a large spectrum of topics, both theoretical and experimental. In addition to explicit advanced calculations of Feynman diagrams and the study of renormalization group strong interaction effects in weak decays, the book is devoted to the Standard Model Effective Theory, dominating present phenomenology in this field, and to new physics models with the goal of searching for new particles and interactions through quantum fluctuations. This book will benefit theorists, experimental researchers, and Ph.D. students working on flavour physics and weak decays as well as physicists interested in physics beyond the Standard Model. In its concern for the search for new phenomena at short distance scales through the interplay between theory and experiment, this book constitutes a travel guide to physics far beyond the scales explored by the Large Hadron Collider at CERN.

This book explores how machine learning can be used to improve the efficiency of expensive fundamental science experiments. The first part introduces the Belle and Belle II experiments, providing a detailed description of the Belle to Belle II data conversion tool, currently used by many analysts. The second part covers machine learning in high-energy physics, discussing the Belle II machine learning infrastructure and selected algorithms in detail. Furthermore, it examines several machine learning techniques that can be used to control and reduce systematic uncertainties. The third part investigates the important exclusive B tagging technique, unique to physics experiments operating at the Υ resonances, and studies in-depth the novel Full Event Interpretation algorithm, which doubles the maximum tag-side efficiency of its predecessor. The fourth part presents a complete measurement of the branching fraction of the rare leptonic B decay “B→tau nu”, which is used to validate the algorithms discussed in previous parts.

This book offers the first strong evidence of the existence of CP violation in neutral B decays extracted from sophisticated B factories in the US and Japan. It also holds out the expectation of rare B decays and D, K physics in the near future. In addition, new physics beyond the Standard Model is described. Both experimental and theoretical points of view are given.

The Standard Model (SM) of particle physics has withstood thus far every attempt by experimentalists to show that it does not describe data. We discuss the SM in some detail, focusing on the mechanism of fermion mixing, which represents one of its most intriguing aspects. We discuss how this mechanism can be tested in b-quark decays, and how b decays can be used to extract information on physics beyond the SM. We review experimental techniques in b physics, focusing on recent results and highlighting future prospects. Particular attention is devoted to recent results from b decays into a hadron, a lepton and an anti-lepton, that show discrepancies with the SM predictions — the so-called B-physics anomalies — whose statistical significance has been increasing steadily. We discuss these experiments in a detailed manner, and also provide theoretical interpretation of these results in terms of physics beyond the SM.

This volume contains contributions to the XXI International Symposium on Lepton and Photon Interactions at High Energies, held at the Fermi National Accelerator Laboratory. It gives up-to-date reviews of all aspects of particle physics, written by leading practitioners in the field. The review nature of all the articles makes this volume more accessible to students and researchers in other fields of physics. In addition to new experimental data and advances in theory, the future directions and prospects for the field are covered.The proceedings have been selected for coverage in:• Index to Scientific & Technical Proceedings® (ISTP® / ISI Proceedings)• Index to Scientific & Technical Proceedings (ISTP CDROM version / ISI Proceedings)• CC Proceedings — Engineering & Physical Sciences

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.