We derive new positivity constraints on the spin-dependent structure functions of nucleon. These model independent results reduce conside\-rably their domain allowed values, in particular for chiral-odd parton distribution $h_1 (x)$.

Colliding beams of 70% polarized protons at up to $\sqrt{s}$=500 GeV, with high luminosity, L=2$\times10^{\rm 32}$ cm$^{-2}$sec$^{-1}$, will represent a new and unique laboratory for studying the proton. RHIC-Spin be first polarized-proton collider capable copious production jets, directly produced photons, $W$ $Z$ bosons. Features include direct precise measurements polarization gluons $\bar{u}$, $\bar{d}$, $u$, $d$ quarks in Parity violation searches physics beyond standard model...

We improve significantly the impact picture that was used several years ago to predict increase of total and integrated differential cross sections at high energies. The major improvements consist following: (1) dependence Pomeron term on momentum transfer is taken from a modified version relation between matter distribution charge distribution, (2) Regge backgrounds are properly into account, (3) simple nontrivial form for hadronic-matter current in proton. For proton-proton elastic...

Regge phenomenology is used to infer the positivity of certain helicity-dependent quark distribution functions with their low-$x$ behavior subtracted out. These forms adequately describe data for muon scattering from polarized protons but violate Ellis-Jaffe sum rule, casting doubt on reliability perturbative QCD. Predictions made earlier theory geometrodynamics are in agreement data.

Motivated by the need for an absolute polarimeter to determine beam polarization forthcoming BNL RHIC spin program, we study dependence of proton-proton elastic scattering amplitudes at high energy and small momentum transfer. In particular, examine experimental evidence existence asymptotic part helicity-flip amplitude ${\ensuremath{\varphi}}_{5}$ which is not negligible relative largely imaginary average nonflip...

We propose a novel mechanism for exclusive diffractive Higgs production $pp\ensuremath{\rightarrow}pHp$ in which the boson carries significant fraction of projectile proton momentum. This will provide clear experimental signal due to small background this kinematic region. The key assumption underlying our analysis is presence intrinsic heavy flavor components bound state, whose existence at high light-cone momentum $x$ has growing and theoretical support. also discuss implications picture...

The recent data at \ensuremath{\surd}s =0.546 TeV from the CERN pp\ifmmode\bar\else\textasciimacron\fi{} collider confirm once more predictions of impact picture, which is based on quantum field theory. These pp and total elastic differential cross sections are extended to higher energies up =40 TeV. They direct interest for future experiments CERN, Fermilab, superconducting super collider.

We show that the strong ${\mathit{Q}}^{2}$ dependence of Gerasimov-Drell-Hearn sum rule is naturally described by using Schwinger rules and contribution ${\mathit{g}}_{2}$ structure function. The deep inelastic proton longitudinal asymmetry expected to change sign around ${\mathit{Q}}^{2}$=0.2 ${\mathrm{GeV}}^{2}$; this important result should be checked experimentally.

We consider the inclusive reaction pp\ensuremath{\rightarrow}\ensuremath{\Lambda}X in fragmentation region and present a dynamical mechanism which leads to fair description of all basic features observed \ensuremath{\Lambda} spectrum. also show simple manner why it generates nonzero polarization whose magnitude $sign--- are consistent with existing data.

A generalization of the Goldberger-Trieman relation for singlet channel is obtained. This gives a new between total quark contribution to proton spin (\ensuremath{\Delta}\ensuremath{\Sigma}) and \ensuremath{\eta}\ensuremath{'}-meson couplign constants (${\mathrm{g}}_{\mathrm{\ensuremath{\eta}}\ensuremath{'}\mathrm{NN}}$ ${\mathrm{f}}_{\mathrm{\ensuremath{\eta}}\ensuremath{'}}$). Using these we find \ensuremath{\Delta}\ensuremath{\Sigma}\ensuremath{\approx}1, precisely as in naive model....

We consider the extension of statistical parton distributions to include their transverse momentum dependence, by using two different methods, one is based on our quantum approach, other a relativistic covariant method. take into account effects Melosh-Wigner rotation for polarized distributions. The results obtained can be compared with recent semi-inclusive deep inelastic scattering (DIS) data cross section and double longitudinal-spin asymmetries from JLab. also give some predictions...

The generalized Gerasimov-Drell-Hearn sum rule is known to be very sensitive QCD radiative and power corrections. We improve the previously developed QCD-inspired model for ${Q}^{2}$ dependence of rule. take into account higher order higher-twist corrections extracted from precise Jefferson Lab data on lowest moment spin-dependent proton structure function ${\ensuremath{\Gamma}}_{1}^{p}({Q}^{2})$ Bjorken ${\ensuremath{\Gamma}}_{1}^{p\ensuremath{-}n}({Q}^{2})$. By using singularity-free...