We calculate the lowest order hadronic cross sections for producing colored heavy quark-antiquark pairs in L = S = 0 and L = S = 1 configurations. J ] long distance matrix elements which can be extracted from the data are generally consistent with NRQCD scaling rules. 4/961

The rare radiative decay b → sγ is studied in SU (2) L × SU (2) R × U (1) extensions of the Standard Model. Matching conditions for coefficients of operators appearing in the low energy effective Hamiltonian for this process are derived, and QCD corrections to these coefficients are analyzed. The b → sγ decay rate is then calculated and compared with the corresponding Standard Model result. We find that observable deviations from Standard Model predictions can occur in SU (2) L × SU (2) R × U (1) theories for a reasonable range of parameter values. 10/93 †

We calculate in closed form the complete O(α 2 s ) color-singlet differential cross section for e + e − → γ * → ψ Q + X scattering. The cross section reduces at high energies to a heavy quark fragmentation form. We find that the energy scale at which the approximate fragmentation result becomes reliable exceeds the ψ Q mass by more than an order of magnitude. We also discuss the colorsinglet model's predictions for direct J/ψ angular and energy distributions at CLEO.

We investigate the implications of spin symmetry for heavy quarkonia production and decay. We first compare spin symmetry predictions for charmonia and bottomonia radiative transitions with data and find they agree quite well. We next use spin symmetry along with nonrelativistic QCD power counting to determine the leading order alignment of P and D-wave orthoquarkonia that are produced through gluon fragmentation. Finally, we discuss a mechanism which may resolve the current factor of 30 discrepancy between theoretical predictions and experimental measurements of prompt $\psi'$ production at the Tevatron. This mechanism involves gluon fragmentation to a subleading Fock component in the $\psi'$ wavefunction and yields 100\% transversely aligned $\psi'$'s to lowest order. Observation of such a large alignment would provide strong support for this resolution to the $\psi'$ problem.Comment: 13 pages, harvmac, 2 uuencoded figure

Two recently discovered excited charm baryons are studied within the framework of heavy hadron chiral perturbation theory. We interpret these new baryons which lie 308 MeV and 340 MeV above the A, as I = 0 members of a P-wave spin doublet. Differential and total decay rates for their double pion transitions down to the A, ground state are calculated. Estimates for their radiative decay rates are also discussed. We find that the experimentally determined characteristics of the A,' baryons may be simply understood within the effective theory.