Related papers: Issues of Spin Physics at RHIC
This talk gives a very short overview of some of the important physical phenomena observed at the Relativistic Heavy Ion Collider (RHIC). The emphasis is put on the multiplicities, hard probes and the properties of the initial state.
The STAR collaboration aims to study polarized proton-proton collisions at RHIC. The emphasis of the spin run this year is on transverse single spin asymmetries. Beyond 2001, we aim to determine directly and precisely the gluon…
I discuss the present situation with regard to a variety of theoretical topics in hadronic spin physics: (a) global analysis of the g1 data---positivity at leading and next-to-leading order, renormalisation-scheme dependence,…
Spin is commonly thought to reflect the true quantum nature of microphysics. We show that spin is related to intrinsic and field-like properties of single particles. These properties change continuously in external magnetic fields.…
We present a recent calculation of the Wigner distributions of quarks and gluons in a perturbative model. We also present the results for the orbital angular momentum and the spin-orbit correlations.
The STAR experiment uses polarized p+p collisions at RHIC to determine the contributions to the spin of the proton from gluon spin and from orbital angular momentum of the quarks and gluons. Selective STAR measurements of the longitudinal…
The proton spin budget is discussed. Results are presented from inclusive and semi-inclusive deep inelastic scattering and from deeply virtual Compton scattering. They permit interpretations towards the determination of various…
Analytical and numerical results, for the orbital and spin content carried by different quark flavors in the baryons, are given in the chiral quark model with symmetry breaking. The reduction of the quark spin, due to the spin dilution in…
The relativistic treatment of spin is a fundamental subject which has an old history. In various physical contexts it is necessary to separate the relativistic total angular momentum into an orbital and spin contribution. However, such…
This paper analyzes the algebraic and physical properties of the spin and orbital angular momenta of light in the quantum mechanical framework. The consequences of the fact that these are not angular momenta in the quantum mechanical sense…
We discuss the tremendous progress that has been towards an understanding of how the spin of the proton is distributed on its quark and gluon constituents. This is a problem that began in earnest twenty years ago with the discovery of the…
The 2(2s+1)-component relativistic basis spinors for the arbitrary spin particles are established in position, momentum and four-dimensional spaces, where s=0,1 / 2,1, 3 / 2, 2, ... . These spinors for integral- and half-integral spins are…
The self-gravitating, spherically symmetric thin shells built of orbiting particles are sstudied. Two new features are found. One is the minimal possible value for an angular momentum of particles, above which elleptic orbits become…
Polarized proton-proton collisions at the Relativistic Heavy Ion Collider (RHIC) provide unique opportunities to study the spin structure of the nucleon. We will highlight recent results on the nucleon spin structure from the STAR and…
The relatively small fraction of the spin of the proton carried by its quarks presents a major challenge to our understanding of the strong interaction. Traditional efforts to explore this problem have involved new and imaginative…
The discovery of the topological nature of free-space light and its quantum chiral behavior has recently raised large attention. This important scientific endeavor features spin-based integrated quantum technologies. Herein, we discuss a…
Angular momentum is important concept in physics, and its phase space properties are important in various applications. In this work phase space analysis of the angular momentum is made from its classical definition, and by imposing…
I describe a few of the most exciting open questions in high energy spin physics. After a brief look at (g-2)_\mu and the muon electric dipole moment, I concentrate on QCD spin physics. Pressing questions include the interpretation of new…
We consider impact parameter dependence of the polarized and unpolarized structure functions. Unitarity does not allow factorization of the structure functions over the Bjorken x and the impact parameter b variables. On the basis of the…
Status, open questions, and future prospects of the physics of excited nucleons are discussed. Emphasis is on the study of the structure of nucleons via measurements of their electromagnetic transition form factors, the search for "missing"…