Describes the technology and engineering of the Large Hadron collider (LHC), one of the greatest scientific marvels of this young 21st century. This book traces the feat of its construction, written by the head scientists involved, placed into the context of the scientific goals and principles.

This book introduces the physics and technology of the High-Luminosity Large Hadron Collider (LHC), highlighting the most recent modifications that shaped the final configuration, which is now in the advanced stages of its construction.This new High-Luminosity configuration of the LHC is the major accelerator project of this decade and will give new life to the LHC after its first fifteen years of operation, allowing for more precise measurements of the Higgs Boson and extending the mass limit reach for new particles.The LHC is such a highly optimized machine that upgrading it requires breakthroughs in many areas. Unsurprisingly, the High-Luminosity LHC required a long R&D period to bring into life an innovative accelerator magnet, based on Nb3Sn and capable of generating fields in the 11-12 T range, as well as many other new accelerator technologies such as superconducting compact RF crab cavities, advanced collimation concepts, a novel powering technology based on high temperature superconducting links, and others.The book is a self-consistent series of papers, which addresses all technology and design issues. Each paper can be read separately as well. The first few papers provide a summary of the whole project, the physics motivation, and the accelerator challenges. Altogether, this book brings the reader to the heart of the technologies that will also be key for the next generation of hadron colliders.This book is an essential reference for physicists and engineers in the field of hadron colliders and LHC related issues and can also be read by postgraduate students.

This book presents the first global interpretation of measurements of jet and top quark production at the Large Hadron Collider, including a simultaneous extraction of the standard model parameters together with constraints on new physics, unbiased from the assumptions on the standard model parameters. As a long-standing problem, any hadron collider search for new physics depends on parton distribution functions, which cannot be predicted but are extracted experimentally. However, performing the extraction in the same kinematic region where physics beyond the standard model is expected to manifest causes the risk of absorbing the new physics effects into the parton distributions. In this book, the issue is addressed by extending the standard model by effective contributions from quark contact interactions describing new physics and extracting the parton distributions and standard model parameters simultaneously with setting limits on the contact interactions. In the process, the most precise single measurement of the strong coupling constant at the LHC is performed, to date. Furthermore, the book details the first investigation of the mass renormalization scale dependence of the top quark mass, highlighting the importance of a proper scale choice for obtaining robust predictions and improving the precision of experimental analyses. The initial chapters provide the reader with a succinct yet accessible introduction to the relevant theoretical and experimental topics. The presented investigations are at the edge of precision in the phenomenology of high-energy physics and serve to pave the road toward a global interpretation of LHC data.

In 1964, a mechanism explaining the origin of particle masses was proposed by Robert Brout, François Englert, and Peter W. Higgs. 48 years later, in 2012, the so-called Higgs boson was discovered in proton-proton collisions recorded by experiments at the LHC. Since then, its ability to interact with quarks remained experimentally unconfirmed. This book presents a search for Higgs bosons produced in association with top quarks tt̄H in data recorded with the CMS detector in 2016. It focuses on Higgs boson decays into bottom quarks H → bb̅ and top quark pair decays involving at least one lepton. In this analysis, a multiclass classification approach using deep learning techniques was applied for the first time. In light of the dominant background contribution from tt̄ production, the developed method proved to achieve superior sensitivity with respect to existing techniques. In combination with searches in different decay channels, the presented work contributed to the first observations of tt̄H production and H → bb̅ decays.