This book gives an introduction to main ideas used in the physics of ultra-relativistic heavy-ion collisions. The links between basic theoretical concepts (discussed gradually from the elementary to more advanced level) and the results of experiments are outlined, so that experimentalists may learn more about the foundations of the models used by them to fit and interpret the data, while theoreticians may learn more about how different theoretical ideas are used in practical applications. The main task of the book is to collect the available information and establish a uniform picture of ultra-relativistic heavy-ion collisions. The properties of hot and dense matter implied by this picture are discussed comprehensively. In particular, the issues concerning the formation of the quark-gluon plasma in present and future heavy-ion experiments are addressed.

This thesis, which won one of the six 2015 ATLAS Thesis Awards, concerns the study of the charmonium and bottomonium bound heavy quark bound states. The first section of the thesis describes the observation of a candidate for the chi_b(3P) bottomonium states. This represented the first observation of a new particle at the LHC and its existence was subsequently confirmed by D0 and LHCb experiments. The second part of the thesis presents measurements of the prompt and non-prompt production of the chi_c1 and chi_c2 charmonium states in proton-proton collisions. These measurements are compared to several theoretical predictions and can be used to inform the development of theoretical models of quarkonium production.

This thesis discusses in detail the measurement of the polarizations of all S-wave vector quarkonium states in LHC proton-proton collisions with the CMS detector. Heavy quarkonium states constitute an ideal laboratory to study non-perturbative effects of quantum chromodynamics and to understand how quarks bind into hadrons. The experimental results are interpreted through an original phenomenological approach, which leads to a coherent picture of quarkonium production cross sections and polarizations within a simple model, dominated by one single color-octet production mechanism. These findings provide new insights into the dynamics of heavy quarkonium production at the LHC, an important step towards a satisfactory understanding of hadron formation within the standard model of particle physics.

Many high-energy collider experiments (including the current Large Hadron Collider at CERN) involve the collision of hadrons. Hadrons are composite particles consisting of partons (quarks and gluons), and this means that in any hadron-hadron collision there will typically be multiple collisions of the constituents — i.e. multiple parton interactions (MPI). Understanding the nature of the MPI is important in terms of searching for new physics in the products of the scatters, and also in its own right to gain a greater understanding of hadron structure. This book aims at providing a pedagogical introduction and a comprehensive review of different research lines linked by an involvement of MPI phenomena. It is written by pioneers as well as young leading scientists, and reviews both experimental findings and theoretical developments, discussing also the remaining open issues.

This concise primer reviews the latest developments in the field of jets. Jets are collinear sprays of hadrons produced in very high-energy collisions, e.g. at the LHC or at a future hadron collider. They are essential to and ubiquitous in experimental analyses, making their study crucial. At present LHC energies and beyond, massive particles around the electroweak scale are frequently produced with transverse momenta that are much larger than their mass, i.e., boosted. The decay products of such boosted massive objects tend to occupy only a relatively small and confined area of the detector and are observed as a single jet. Jets hence arise from many different sources and it is important to be able to distinguish the rare events with boosted resonances from the large backgrounds originating from Quantum Chromodynamics (QCD). This requires familiarity with the internal properties of jets, such as their different radiation patterns, a field broadly known as jet substructure. This set of notes begins by providing a phenomenological motivation, explaining why the study of jets and their substructure is of particular importance for the current and future program of the LHC, followed by a brief but insightful introduction to QCD and to hadron-collider phenomenology. The next section introduces jets as complex objects constructed from a sequential recombination algorithm. In this context some experimental aspects are also reviewed. Since jet substructure calculations are multi-scale problems that call for all-order treatments (resummations), the bases of such calculations are discussed for simple jet quantities. With these QCD and jet physics ingredients in hand, readers can then dig into jet substructure itself. Accordingly, these notes first highlight the main concepts behind substructure techniques and introduce a list of the main jet substructure tools that have been used over the past decade. Analytic calculations are then provided for several families of tools, the goal being to identify their key characteristics. In closing, the book provides an overview of LHC searches and measurements where jet substructure techniques are used, reviews the main take-home messages, and outlines future perspectives.

The exploration of the subnuclear world is done through increasingly complex experiments covering a wide range of energy and performed in a large variety of environments ranging from particle accelerators, underground detectors to satellites and the space laboratory. Among recent advances one has to indicate, for instance, first results obtained from space and LHC experiments and progress done in preparation of the latter experiments upgrades, including plans for the LHC machine upgrade. The achievement of these research programs calls for novel techniques, new materials and instrumentation to be used in detectors, often of large scale. Therefore, fundamental physics is at the forefront of technological advance and also leads to many applications. Among these, medical applications have a particular importance due to health and social benefits they bring to the public. Sample Chapter(s). Science highlights from the Fenni Observatory (5,046 KB). Contents: Space Experiments and Cosmic Rays Observations; Production and Propagation of Cosmic Rays in the Galaxy and Heliosphere; Dark Matter Searches, Underwater and Underground Experiments; High Energy Physics Experiments; Tracker and Position Sensitive Detectors; Calorimetry; Advanced Detectors, Particles Identication, Devices and Materials in Radiation; Broader Impact Activities, Treatments and Software Application. Readership: Post-graduate students, researchers and engineers.

The Large Hadron Collider (LHC), located at CERN, Geneva, Switzerland, is the world's largest and highest energy and highest intensity particle accelerator. This book provides an overview on the techniques that will be crucial for finding new physics at the LHC, as well as perspectives on the importance and implications of the discoveries. Among the contributors to this book are leaders and visionaries in the field of particle physics beyond the Standard Model, including two Nobel Laureates (Steven Weinberg and Frank Wilczek), and presumably some future Nobel Laureates, plus top younger theorists and experimenters.