26,637 research outputs found

    Mixed harmonic charge dependent azimuthal correlations in Pb-Pb collisions at sNN\sqrt{s_{NN}} = 2.76 TeV measured with the ALICE experiment at the LHC

    Full text link
    Mixed harmonic charge dependent azimuthal correlations at mid-rapidity in Pb-Pb collisions at sNN\sqrt{s_{NN}} = 2.76 TeV were measured with the ALICE detector at the LHC. A clear charge dependence for a series of correlations is observed both via the multi-particle cumulant and the event plane methods. Implications from these measurements for the possible effects of the local parity violation in QCD and for models which incorporate the azimuthal anisotropic flow and the local charge conservation on the kinetic freeze-out surface are discussed.Comment: 4 pages, 7 figures, Proceedings for Quark Matter 2012, Washington D.C., Augest 13-18, 201

    Electroweak Sudakov effect on processes at TeV scale

    Get PDF
    In Next Linear Colliders at TeV scale, electroweak double logarithmic corrections, which come from the infrared behaviors of theory can not be neglected. It is well known that in QED and QCD, double logarithmic corrections are resummed to all orders, and these corrections can be exponentiated, resulting in the Sudakov form factor. However it is never trivial that double logarithmic corrections in electroweak theory can be exponentiated, because of the spontaneous breaking of symmetry and the pattern of that. We discuss the electroweak double logarithmic corrections at two loop level and explain the differences of ``Soft'' structure between the electroweak theory and QCD (the unbroken non-abelian gauge theory).Comment: 5 pages, 17 figures;Talk presented at Theory Meeting on Physics at Linear Colliders, March 15 - 17, 2001, KEK, Japa

    Directed search, rationing and wage dispersion

    Get PDF
    This paper develops a microeconomic model of directed search, where firms are heterogeneous in the number of vacancies advertised, and wages affect workers' choices when both applying for jobs and accepting a job. An aggregate matching function is derived, which incorporates workers' preferences for firms. The aggregate level of matches is shown to be independent of the workers' preferences in the job acceptance stage. When firms' labor demands are heterogeneous, the matching market equilibrium outcome is suboptimal. Matching efficiency is, however, attained in equilibrium, when wages are employed as a rationing device. This results in wage dispersion, despite workers being homogeneous

    Mixed harmonic azimuthal correlations in Pb--Pb collisions at \sqrt{s_{NN}}=2.76TeV measured with the ALICE experiment at the LHC

    Full text link
    Mixed harmonic charge dependent azimuthal correlations at mid-rapidity in Pb-Pb collisions at \sqrt{s_{NN}} = 2.76 TeV were measured with the ALICE detector at the LHC. A clear charge dependence for a series of correlations is observed both via the multi-particle cumulant and the event plane methods. Implications from these measurements for the possible effects of local parity violation in QCD and for models which incorporate azimuthal anisotropic flow and "effective" local charge conservation on the kinetic freeze-out surface are discussed.Comment: 6 pages, 5 figures, proceedings of International symposium on multiparticle dynamics 2012 (ISMD2012

    Calculation of transition probabilities and ac Stark shifts in two-photon laser transitions of antiprotonic helium

    Full text link
    Numerical ab initio variational calculations of the transition probabilities and ac Stark shifts in two-photon transitions of antiprotonic helium atoms driven by two counter-propagating laser beams are presented. We found that sub-Doppler spectroscopy is in principle possible by exciting transitions of the type (n,L)->(n-2,L-2) between antiprotonic states of principal and angular momentum quantum numbers n~L-1~35, first by using highly monochromatic, nanosecond laser beams of intensities 10^4-10^5 W/cm^2, and then by tuning the virtual intermediate state close (e.g., within 10-20 GHz) to the real state (n-1,L-1) to enhance the nonlinear transition probability. We expect that ac Stark shifts of a few MHz or more will become an important source of systematic error at fractional precisions of better than a few parts in 10^9. These shifts can in principle be minimized and even canceled by selecting an optimum combination of laser intensities and frequencies. We simulated the resonance profiles of some two-photon transitions in the regions n=30-40 of the \bar{p}^4He^+ and \bar{p} ^3He^+ isotopes to find the best conditions that would allow this.Comment: 18 pages 2 tables 12 figures, submitted to Phys. Rev.
    corecore