Next-to-leading order QCD corrections to Higgs production at a future lepton-proton collider

Crucial information on the coupling of the Higgs boson to bottom quarks is expected from Higgs production in association with a forward tagging jet at a future high-energy lepton-proton collider. In order to control the theoretical uncertainties of the signal process, the impact of radiative corrections has to be quantified. We present the full next-to-leading order QCD corrections to e- p -> e- j H and e- p -> nu_e j H in the form of a flexible Monte-Carlo program allowing for the calculation of cross sections and kinematic distributions within experimentally feasible selection cuts. QCD corrections are found to be very small for cross sections, while the shape distortion of distributions can be as large as 20%. Residual scale uncertainties at next-to-leading order are at the permille level.Comment: 15 pages, 14 figure

Hard exclusive photoproduction of Φ\Phi and J/ΨJ/\Psi mesons

We present predictions for differential cross sections for the reaction $\gamma p \to \Phi p$ and give an outlook to which extent our calculations may be generalized to the photoproduction of $J/\Psi$ mesons. Our results are obtained within perturbative QCD treating the proton as a quark-diquark system.Comment: 4 pages, 1 figure, uses Elsevier style espcrc1.st

Effect of polarized gluon distribution on spin asymmetries for neutral and charged pion production

A longitudinal double spin asymmetry for \pi^0 production has been measured by the PHENIX collaboration. The asymmetry is sensitive to the polarized gluon distribution and is indicated to be positive by theoretical predictions. We study a correlation between behavior of the asymmetry and polarized gluon distribution in neutral and charged pion production at RHIC.Comment: 7 pages, 5 eps figures, section added, typos corrected. to be published in PR

Quenches across the self-organization transition in multimode cavities

A cold dilute atomic gas in an optical resonator can be radiatively cooled by coherent scattering processes when the driving laser frequency is tuned close but below the cavity resonance. When sufficiently illuminated, moreover, the atoms' steady state undergoes a phase transition from homogeneous density to crystalline order. We characterize the dynamics of this self-ordering process in the semi-classical regime when distinct cavity modes with commensurate wavelengths are quasi-resonantly driven by laser fields via scattering by the atoms. The lasers are simultaneously applied and uniformly illuminate the atoms, their frequencies are chosen so that the atoms are cooled by the radiative processes, their intensity is either suddenly switched or slowly ramped across the self-ordering transition. Numerical simulations for different ramp protocols predict that the system exhibits long-lived metastable states, whose occurrence strongly depends on initial temperature, ramp speed, and number of atoms.Comment: 15 pages, 20 figure