Related papers: Hadron Structure and Modern Spectroscopy
The current status of the accepted glueball candidates is reviewed. The difference between bare and dressed hadrons is emphasised. What two photon processes, both production and decay, have taught us about these is discussed.
A brief survey is presented of recently discovered hadrons, some of them presumably demonstrating a new kind of internal structure. This includes : spin-singlet quarkonium, mesons with unexpected mass or width, baryons with two heavy…
I review some outstanding issues in meson spectroscopy. The most important qualitative issue is whether hadrons with explicit gluonic degrees of freedom exist. To answer this question requires a much better understanding of conventional…
States beyond those expected in the simple constituent quark model are now emerging. I focus on the scalar glueball and its mixing with states in the $q\bar{q}$ nonet, and also on correlations in Strong QCD that may form diquarks and seed…
We present preliminary results from a high statistics study of 2-color QCD at low temperature and non-zero baryon density. The simulations are carried out on a 6^3*12 lattice and use a standard hybrid molecular dynamics algorithm for…
In this talk the pomeron conjecture is reviewed and constituent gluon models are derived. In a simple two-gluon glueball spectrum the pomeron trajectory and the daughter trajectories are computed. The open problems of two-gluon glueballs…
A new phenomenological cluster-hadronization model is presented. Its specific features are the incorporation of soft colour reconnection, a more general treatment of diquarks including their spin and giving rise to clusters with baryonic…
For some experimental guidelines of the next millenium, I review the determinations of the masses, decays and mixings of the gluonia, scalar and hybrid mesons from QCD spectral sum rules and low-energy theorems, and compare them with the…
The use of lattice QCD to understand hadron structure is described, with particular emphasis on exploring the role of glue.
Glueballs are particles whose valence degrees of freedom are gluons and therefore in their description the gauge field plays a dominant role. We review recent results in the physics of glueballs with the aim set on phenomenology and discuss…
We suggest a theoretical framework for the description of double photon and proton-antiproton photoproduction off the proton gamma + p -> 2 gamma + p and gamma + p -> antip + p + p which takes into account the contribution of the scalar…
Based on the general analysis of branching ratio of two pseudoscalar meson channels, discriminants between mesons and glueballs for $I=0, J^{PC}=even^{++}$ unflavored hadrons with mass between 1.2 GeV and 2.9 GeV are suggested. Known $I=0,…
Hadron structure advances provided by the Coulomb gauge model are summarized. Highlights include a realistic description of the vacuum and meson spectrum with chiral symmetry and dynamical flavor mixing, accurate hyperfine splittings for…
A review of the theoretical and experimental status of hybrid hadrons is presented. The states $\pi_1(1400)$, $\pi_1(1600)$, and $\pi_1(2015)$ are thoroughly reviewed, along with experimental results from GAMS, VES, Obelix, COMPASS, KEK,…
This compact review about gluonium focuses on a slate of theoretical efforts; among the many standing works, I have selected several that are meant to assist in the identification, among ordinary mesons, of the few Yang-Mills glueball…
Glueballs and Hybrids are solid predictions of QCD, but none have this far been identified in an undisputable way. We list several strategies, including the very promising search for "cascade" decays of glueballs and hybrids into each…
An elementary introduction is presented to the study of hadron structure using lattice QCD. Following a brief review of relevant aspects of path integrals, the discrete lattice path integral is presented for gluon and quark fields and used…
The mixing between the $f_2(1270)$, the $f_2(1525)$, and the $2^{++}$ glueball is determined and tested. The mass and the hadronic decay widths of the $G_2$ and the branching ratio $B(J/\psi\rightarrow\gamma G_2)$ are predicted.
Central exclusive production in hadron-hadron collisions at high energies, for example p + p -> p + X + p, where the "+" represents a large rapidity gap, is a valuable process for spectroscopy of mesonic states X. At collider energies the…
Results of experiments probing the structure of the pomeron at hadron colliders and at HERA are reviewed. By renormalizing the pomeron flux factor in diffraction dissociation as dictated by unitarity, a picture emerges from the data in…