Υ\Upsilon Polarization at HERA-BB

The production of $\Upsilon$ mesons in fixed target $pN$ collisions is considered. It is shown that Non-Relativistic QCD predicts $\Upsilon$ states to be produced with sizeable transverse polarization. The possibility of a measurement of the $\Upsilon$ polarization at the HERA-$B$ experiment is discussed.Comment: 9 pages, LaTeX, with 3 eps figs included with epsfig.st

Bottomonium Polarization in Hadroproduction

The polarization of the $\Upsilon$ and $\chi_{b2}$ mesons in hadron collisions is considered. It is shown that both states are produced with a noticeable polarization which allows to use forthcoming data of DESY HERA-B and of the RHIC collider experiments to discriminate between the different mechanisms of heavy quarkonia production

Target Mass Corrections to the Spin-dependent Structure Functions

The target mass corrections to the twist-2 contributions of the spin-dependent structure functions are calculated using operator product expansion in lowest order in QCD. The influence of such corrections to the different relations between the structure functions is considered.Comment: 2 pages LATEX, contract number adde

Color Octet Contribution to J/ψJ/\psi Production at a Photon Linear Collider

We investigate $J/\psi$ production at a Photon Linear Collider (PLC) in the framework of NRQCD factorization approach. It was shown that color octet contribution is dominating in charmonium production at PLC. The main fraction of $J/\psi$ comes from the single and double resolved photon processes. Expected cross sections of charmonium states production are large enough even at $p_T>5$ GeV to expect several hundreds of $J/\psi$'s through the leptonic decays channel for a projected integral PLC luminosity of $50 fb^{-1}$}Comment: 10 pages, LaTeX, with 4 eps figs included with epsfig.st

Color Octet Contribution to J/psi Photoproduction Asymmetries

We investigate $J/\psi$ photoproduction asymmetries in the framework of the NRQCD factorization approach. It is shown that the color octet contribution leads to large uncertainties in the predicted asymmetries which rules out the possibility to precisely measure the gluon polarization in the nucleon through this final state. For small values of the color octet parameters being compatible with $J/\psi$ photoproduction data it appears possible that a measurement of $J/\psi$ asymmetries could provide a new test for the NRQCD factorization approach, on one hand, or a measurement of the polarized gluon distribution from low inelasticity events $(z<0.7)$, on the otherComment: 12 pages, LaTeX, with 6 figs. Final version published in Phys.Rev.