234 research outputs found

    Neutrino-nucleon cross sections at energies of Megaton-scale detectors

    Full text link
    An updated set of (anti)neutrino-nucleon charged and neutral current cross sections at 3 GeVEν100 GeV3~{\rm GeV} \lesssim E_\nu \lesssim 100~{\rm GeV} is presented. These cross sections are of particular interest for the detector optimization and data processing and interpretation in the future Megaton-scale experiments like PINGU, ORCA, and Hyper-Kamiokande. Finite masses of charged leptons and target mass corrections in exclusive and deep inelastic (νˉ)νN(\bar\nu)\nu N interactions are taken into account. A new set of QCD NNLO parton density functions, the ABMP15, is used for calculation of the DIS cross sections. The sensitivity of the cross sections to phenomenological parameters and to extrapolations of the nucleon structure functions to small xx and Q2Q^2 is studied. An agreement within the uncertainties of our calculations with experimental data is demonstrated.Comment: 4 pages, 4 figures, accepted for the VLVnT-2015 Conference proceedings, will be published on EPJ Web of Conference

    ANIS: High Energy Neutrino Generator for Neutrino Telescopes

    Full text link
    We present the high-energy neutrino Monte Carlo event generator ANIS (All Neutrino Interaction Simulation). The program provides a detailed and flexible neutrino event simulation for high-energy neutrino detectors, such as AMANDA, ANTARES or ICECUBE. It generates neutrinos of any flavor according to a specified flux and propagates them through the Earth. In a final step neutrino interactions are simulated within a specified volume. All relevant standard model processes are implemented. We discuss strengths and limitations of the program.Comment: 15 pages, 4 figure

    Particle swarm optimization of broadband field enhancement with a grating-assisted plasmonic taper nanoantenna

    Get PDF
    This work is dedicated to the improvement of the near-field enhancement beneath the gold and silver tip apex due to plasmons excitation on a sub-wavelength grating engraved on the tip lateral surface. To study conditions of the maximal enhancement we have performed PSO-based optimization of intensity in search space of two parameters for gold and silver tip with different cone angles. Parameters of search space are period of the grating and its position in respect to the apex. The grating-assisted tip is illuminated with the incident light with wavelengths of 400 to 1000 nm in our model. All the simulations of electromagnetic waves scattering on the nanoantenna are based on the finite difference time domain method

    Longitudinal polarizability and enhancement factor of a tapered optical gold nanoantenna

    Get PDF
    This work focuses on the mechanism of electric field enhancement near a tapered optical antenna and the calculation of a complex field enhancement factor as a function of tip material, its curvature radius and cone angle. In this paper, an analytical model of longitudinal polarizability, taking into account retardation and dynamic polarization effects, is developed for evaluating the field enhancement factor

    Improvement of near-field enhancement with a grating-assisted gold tapered nanoantenna

    Get PDF
    This work is dedicated to the improvement of the near-field enhancement beneath the tip apex due to delocalized plasmons excitation on a sub-wavelength grating engraved on the tip mesoscopic surface. To study conditions of the maximal enhancement we have performed PSO-based optimization of intensity in search space of two parameters. Those parameters are period of the grating and its position in respect to the apex. The grating- patterned tip is illuminated with the incident light with wavelengths of 400 to 1000 nm in our model. All the simulations of electromagnetic waves scattering on the nanoantenna are based on the finite difference time domain method

    Optical near-field scattering in a tip-sample system: A Green's function approach

    Get PDF
    The optical near-field contribution to the total scattered intensity for a spherical metallic nanoparticle close to a dielectric planar interface is analytically calculated using a Green's function formalism. This system is suited for probing a specimen of interest on a dielectric substarte with a taper optical metallic nanoantenna. Based on the effective polarizability model we find a Green's function in the dipolar approximation, that allows one take into account the presence of the dielectric substrate. In particular, we provide evidence that the latter noticably influences the near-field contribution and it should necessarily be included in the generalized formalism for calculating the Green's functions for Raman scattering and fluorescence. A comparative analysis of the analytical model and finite-difference time domain based numerical simulation is performed. © Published under licence by IOP Publishing Ltd

    Improvement of near-field enhancement with a grating-assisted gold tapered nanoantenna

    Get PDF
    This work is dedicated to the improvement of the near-field enhancement beneath the tip apex due to delocalized plasmons excitation on a sub-wavelength grating engraved on the tip mesoscopic surface. To study conditions of the maximal enhancement we have performed PSO-based optimization of intensity in search space of two parameters. Those parameters are period of the grating and its position in respect to the apex. The grating- patterned tip is illuminated with the incident light with wavelengths of 400 to 1000 nm in our model. All the simulations of electromagnetic waves scattering on the nanoantenna are based on the finite difference time domain method

    4.各部門の活動内容 薬局

    Get PDF
    This work is dedicated to the improvement of the near-field enhancement beneath the tip apex due to delocalized plasmons excitation on a sub-wavelength grating engraved on the tip mesoscopic surface. To study conditions of the maximal enhancement we have performed PSO-based optimization of intensity in search space of two parameters. Those parameters are period of the grating and its position in respect to the apex. The grating- patterned tip is illuminated with the incident light with wavelengths of 400 to 1000 nm in our model. All the simulations of electromagnetic waves scattering on the nanoantenna are based on the finite difference time domain method

    Laser field distribution near inclined taper optical antenna

    Get PDF
    © Published under licence by IOP Publishing Ltd. This work focuses on the mechanism of laser field enhancement within a gap between a taper plasmonic nanoantenna and a dielectric substrate in the inverted optical configuration. We show that field enhancement factor depends on several parameters such as: tip-sample distance, radius of curvature of the tip and its inclination angle in respect to the substrate. In particular, a relation between the field enhancement near the tip apex and the inclination angle is deduced. Numerical simulation and optimization were performed within the framework of the FDTD method and the Green function formalism
    corecore