Magnetic moments of octet baryons and sea antiquark polarizations

Using generalized Sehgal equations for magnetic moments of baryon octet and taking into account $\Sigma^{0}-\Lambda$ mixing and two particle corrections to independent quark contributions we obtain very good fit using experimental values for errors of such moments. We present sum rules for quark magnetic moments ratios and for integrated spin dendities ratios. Due to the SU(3) structure of our equations the results for magnetic moments of quarks and their densities depend on two additional parameters. Using information from deep inelastic scattering and baryon $\beta$-decays we discuss the dependence of antiquark polarizations on introduced parameters. For some plausible values of these parameters we show that these polarizations are small if we neglect angular momenta of quarks. Our very good fit to magnetic moments of baryon octet can still be improved by using specific model for angular momentum of quarks.Comment: Latex, 19 pages 5 eps figures, 2 references added, changes in text to apear in Phys. Rev.

Strong exciton-plasmon coupling in semiconducting carbon nanotubes

We study theoretically the interactions of excitonic states with surface electromagnetic modes of small-diameter (~1 nm) semiconducting single-walled carbon nanotubes. We show that these interactions can result in strong exciton-surface-plasmon coupling. The exciton absorption line shape exhibits Rabi splitting ~0.1 eV as the exciton energy is tuned to the nearest interband surface plasmon resonance of the nanotube. We also show that the quantum confined Stark effect may be used as a tool to control the exciton binding energy and the nanotube band gap in carbon nanotubes in order, e.g., to bring the exciton total energy in resonance with the nearest interband plasmon mode. The exciton-plasmon Rabi splitting we predict here for an individual carbon nanotube is close in its magnitude to that previously reported for hybrid plasmonic nanostructures artificially fabricated of organic semiconductors on metallic films. We expect this effect to open up paths to new tunable optoelectronic device applications of semiconducting carbon nanotubes.Comment: 22 pages, 8 figures, accepted for PR

Desulfurization Effects on a Light-Duty Diesel Vehicle NOx Adsorber Exhaust Emission Control System

Analyzes the effects on gaseous emissions, before and after desulfurization, on a light-duty diesel vehicle with a NOx adsorber catalyst