Mesons And Baryons Systematization And Methods Of Analysis

This book is devoted to the investigation of the strongly interacting hadrons — to a quark model operating with effective color particles, constituent quarks, massive effective gluons and diquarks. The study of strong interactions based on effective constituent particles requires a solid ground of experimental data, which we now have at our disposal with the serious progress made in the investigation of hadrons, especially meson states.The present understanding of QCD applied to strong interactions can be distorted by prejudices. Therefore, the way followed by the quark model is to rely on the experiment and to restore the effective Hamiltonian on the basis of QCD on the one hand, and, on the other, of the spectral integral method.Baryon-baryon and antibaryon-baryon interactions are studied with the purpose of unambiguous applications of the written formulae to the interpretation of experimental data — to the observation of new meson and baryon resonances. The technique used is the spin-orbital momentum expansion of the amplitude. This method is our basic approach to the proper treatment of experimental data. The photon-induced reactions are also considered and the problem of form factors is discussed.

The necessity of describing three-nucleon and three-quark systems have led to a constant interest in the problem of three particles. The question of including relativistic effects appeared together with the consideration of the decay amplitude in the framework of the dispersion technique. The relativistic dispersion description of amplitudes always takes into account processes connected with the investigated reaction by the unitarity condition or by virtual transitions; in the case of three-particle processes they are, as a rule, those where other many-particle states and resonances are produced. The description of these interconnected reactions and ways of handling them is the main subject of the book.

This work originated in a series of lectures on meson and baryon ex cited states which I gave at the Stanford Linear Accelerator Center in the fall of 1962. The notes of these lectures were issued as a Stanford Uni versity report (SLAC-13) in March, 1963. In the fall of 1963, I gave a revised set of lectures on meson and baryon spectroscopy at Indiana University. In both cases, the talks were given primarily for experi mental physicists. In preparing the notes of these talks for pUblication, I have added some introductory material on pions, nucleons, kaons, and hyperons. My main emphasis is on the experimental facts concerning the spectros copy of the mesons and baryons and on the use of conservation laws in their interpretation. I have either mentioned briefly or omitted entirely explanations which depend on dynamical models. Although I have given a number of facts about the electromagnetic and weak decays of some mesons and baryons, I have not discussed the theory of these decays. This is not a comprehensive review of the subject of the strongly interacting particles, and the list of references is not complete. Also, I have not always devoted time to a subject in proportion to its impor tance, but have spent more time on topics which have particularly interested me. Nevertheless, I hope that I have provided a useful summary of the most important facts about the spectroscopy of the mesons and baryons.

This is an updated version of the book published in 1985. QCD-motivated, it gives a detailed description of hadron structure and soft interactions in the additive quark model, where hadrons are regarded as composite systems of dressed quarks.In the past decade it has become clear that nonperturbative QCD, responsible for soft hadronic processes, may differ rather drastically from perturbative QCD. The understanding of nonperturbative QCD requires a detailed investigation of the experiments and the theoretical approaches. Bearing this in mind, the book has been rewritten paying special attention to the interplay of soft hadronic collisions and the quark model. It is at the crossroads of these domains that peculiar features of strong QCD reveal themselves.The book discusses constituent quarks, diquarks, the massive effective gluons and the problem of scalar isoscalar mesons. The quark-gluonium classification of meson states is also given. Experimentally observed properties of hadrons are presented together with the corresponding theoretical interpretation in the framework of the composite hadron structure.The text includes a large theoretical part, which shows how to treat composite systems (including relativistic ones) with a technique based on spectral integration. This technique provides the possibility of handling hadrons as weakly bound systems of quarks and, at the same time, takes into account confinement.Attention is focused on the composite structure revealing itself in high energy hadron collisions. Fields of applicability of the additive quark model are discussed, as is colour screening in hadronic collisions at high and superhigh energies. Along with a detailed presentation of hadron-hadron collisions, a description of hadron-nucleus collisions is given.

This book provides a comprehensive overview of modern particle physics accessible to anyone with a true passion for wanting to know how the universe works. We are introduced to the known particles of the world we live in. An elegant explanation of quantum mechanics and relativity paves the way for an understanding of the laws that govern particle physics. These laws are put into action in the world of accelerators, colliders and detectors found at institutions such as CERN and Fermilab that are in the forefront of technical innovation. Real world and theory meet using Feynman diagrams to solve the problems of infinities and deduce the need for the Higgs boson.Facts and Mysteries in Elementary Particle Physics offers an incredible insight from an eyewitness and participant in some of the greatest discoveries in 20th century science. From Einstein's theory of relativity to the spectacular discovery of the Higgs particle, this book will fascinate and educate anyone interested in the world of quarks, leptons and gauge theories.This book also contains many thumbnail sketches of particle physics personalities, including contemporaries as seen through the eyes of the author. Illustrated with pictures, these candid sketches present rare, perceptive views of the characters that populate the field.The Chapter on Particle Theory, in a pre-publication, was termed 'superbly lucid' by David Miller in Nature (Vol. 396, 17 Dec. 1998, p. 642).