Some mass relations for mesons and baryons in Regge phenomenology

In the quasilinear Regge trajectory ansatz, some useful linear mass inequalities, quadratic mass inequalities and quadratic mass equalities are derived for mesons and baryons. Based on these relations, mass ranges of some mesons and baryons are given. The masses of bc-bar and ss-bar belonging to the pseudoscalar, vector and tensor meson multiplets are also extracted. The J^P of the baryon Xi_cc(3520) is assigned to be 1/2^+. The numerical values for Regge slopes and intercepts of the 1/2^+ and 3/2^+ SU(4) baryon trajectories are extracted and the masses of the orbital excited baryons lying on the 1/2^+ and 3/2^+ trajectories are estimated. The J^P assignments of baryons Xi_c(2980), Xi_c(3055), Xi_c(3077) and Xi_c(3123) are discussed. The predictions are in reasonable agreement with the existing experimental data and those suggested in many other different approaches. The mass relations and the predictions may be useful for the discovery of the unobserved meson and baryon states and the J^P assignment of these states.Comment: 41 pages, 1 figure, Late

Associated J/ψ+γJ/\psi + \gamma production as a probe of the polarized gluon distribution

Associated production of $J/\psi$ and a $\gamma$ has recently been proposed as clean probe of the gluon distribution. The same mechanism can be used to probe the polarized gluon content of the proton in polarized proton-proton collisions. We study $J/\psi + \gamma$ production at both polarized fixed target and polarized collider energies.Comment: 16 pages (10 figures available from M.A.D.), MAD/PH/745, SNUTP 93-6, YUMS 93-

Asymmetry in Charmed Particles Production in Σ−\Sigma^{-} beam

We present the calculation of the inclusive $x_F$-distributions of charmed hadrons, produced in high-energy $\Sigma^-$-beam. The calculation is based on the modified mechanism of charmed quarks fragmentation as well as on the mechanism of $c$-quark recombination with the valence quarks from initial hadrons. We predict the additional asymmetry in the production of charmed hadrons due to the different distributions of the valence s and d quarks in $\Sigma^-$-beam.Comment: 19 pages, Latex, 6 figure

Hadronic WW production and the Gottfried Sum Rule

The difference in production rate between $W^+$ and $W^-$ at hadron colliders is very sensitive to the the difference between up- and down-quark distributions in the proton. This sensitivity allows for a variety of useful measurements. We consider the difference $d_s(x,Q^2) - u_s(x,Q^2)$ in the sea distributions and the difference $\Delta u(x,Q^2) - \Delta d(x,Q^2)$ in the polarized parton distribution functions. In both cases we construct an asymmetry to reduce systematic uncertainties. Although we discuss measurements at the Tevatron and future hadron colliders, we find that the Brookhaven Relativistic Heavy Ion Collider (RHIC) is the most appropriate hadron collider for these measurements.Comment: 19 pages (20 figures available from the authors), MAD/PH/74

Aspects of χ\chi and ψ\psi Production in Polarized Proton-Proton Collisions

Several topics of relevance to low transverse momentum $\psi$ and $\chi_{1,2}(c\overline{c})$ production in polarized proton-proton collisions are discussed. The leading ${\cal O}(\alpha_S^3)$ contributions to the low $p_T$ $\chi_1$ production cross-sections via $gg$, $qg$, and $q\overline{q}$ initial states are calculated as well as the corresponding spin-spin asymmetries. We find that $\chi_1$ production increases relative to direct $\psi$ and $\chi_2$ production, providing up to $25\%$ of the observable $e^+e^-$ pairs arising from $\psi$ decays in $pp$ collisions at $\sqrt{s} = 500\,GeV$. The spin-dependence of $\chi_1$ production, however, is much smaller than for either direct $\psi$ or $\chi_2$ production and so will likely be far less useful than either process in probing the polarized gluon structure function of the proton. A subset of the ${\cal O}(\alpha_S^3)$ radiative corrections to $\chi_2$ production involving initial state quarks are also performed and compared to leading order $gg \rightarrow \chi_2$ predictions.Comment: 21 pages + 5 postscript figures (included), OCIP/C-94-