Spin in particle physics (Q2748479)

In the book the exposition of the modern spin (proper angular momentum) theory and the history of its crucial role in the elementary particle physics are presented in the systematical extended form. The basic theoretical investigations and development as well as the experimental achievements of recent years in the spin physics are considered in detail. Exciting plans for the future experimental research are also discussed. The importance of spin-dependent experiments in testing of the quantum chromodynamics (QCD) and the standard model of electroweak interactions (SM) is especially outlined. NEWLINENEWLINENEWLINEThe following main peculiarities of the book are indicated by the author: (i) An approach based upon helicity formalism is developed which leads to a unified treatment for arbitrary exclusive and inclusive interaction processes of polarized particles. (ii) An attempt is made to present and explain some of the last dramatic achievements in the experimental spin physics, first of all, related to the known extraordinary results (``spin crisis'') obtained in CERN in studying electron-proton deep inelastic scattering (1987-89, European Muon Collaboration).NEWLINENEWLINENEWLINEThe book is organized as follows: 1. Spin and helicity (pp. 1-17): spin in non-relativistic and relativistic quantum mechanics, physical interpretation of helicity and canonical spin states, particles with non-zero and zero masses. 2. The effect of Lorentz and discrete symmetry transformations of helicity states, fields and wave functions (18-37): examples of Wick and Wigner transformations, transformation from center of masses (CM) to laboratory (Lab) reference frames; space parity, time reversal and charge conjugation transformations; isospin multiplets for antiparticles. 3. The spin density matrix (38-72): non-relativistic and relativistic cases, choice of reference frames for a reaction, covariant spin vectors. 4. Transition amplitudes (73-91): helicity amplitudes for elastic and pseudo-elastic reactions, symmetry properties of helicity amplitudes, structure of interaction matrix elements, vector and axial vector couplings. 5. The observables of reactions (92-128): generalized optical theorem, CM (Lab) observables and experimental determination of CM (Lab) parameters, applications, multiparticle and inclusive reactions. 6. The production of polarized hadrons (129-164): polarized proton sources and targets, acceleration of polarized particles, polarized secondary and tertiary beams. 7. The production of polarized electrons and positrons (165-184): natural electron polarization in storage rings, polarization on LEP, HERA and SLAC. 8. Analysis of polarized states: polarimetry (185-233): stable and unstable particles, cases of understood and unknown reactions mechanisms; two- and three-particle decays of \(J\)-resonance. 9. Electroweak interactions (234-257): summary and precision tests of SM, productions of fermion-antifermion and quark-antiquark pairs in electron-positron annihilation. 10. Quantum chromodynamics: spin in the world of massless partons (258-297): brief introduction and local gauge invariance in QCD, Feynman rules and helicity theorem for massless fermions, spin structure from a fermion line, massive spinors, polarization vectors, shorthand notation for spinor products, gluon and multigluon amplitudes, colour structure and colour sums. 11. The spin of the nucleon: polarized deep inelastic scattering (298-347): general formalism and structure functions \(g_1(x)\) and \(g_2(x)\) in deep inelastic scattering, simple parton model and its field-theoretical generalization, moments of the structure functions, spin rules and the spin crisis, QCD corrections and evolution, phenomenological polarized parton distributions, general partonic structure of the nucleon. 12. Two-spin and parity violating single-spin asymmetries at large scale (348-381): inclusive and semi-inclusive reactions, longitudinal asymmetries in Drell-Yan reactions and in gauge weak boson production, transverse two-spin asymmetries. 13. One-particle inclusive transverse single-spin asymmetries (382-412): standard and beyond the standard QCD-parton models, Collins mechanism, phenomenological Lund and Thomas precession models. 14. Elastic scattering at high energies (413-432): small momentum transfer, electromagnetic interference effects, asymptotic behavior and complication of exclusive reactions in elastic scattering at large momentum transfer.NEWLINENEWLINENEWLINEAppendices (435-485): irreducible rotation group representation matrices and rotation functions, homogeneous Lorentz transformations and their representations, spin properties of fields and wave equations, transversity and helicity amplitudes; Cartesian, Argonne Lab and linearly independent parameters for various reactions and their relations to helicity amplitudes; Feynmann rules for QCD, Dirac spinors and matrix elements. NEWLINENEWLINENEWLINEReferences 302. The book is addressed to graduate students and researchers working in elementary particle and high energy physics.