Now showing items 43-62 of 1380

  • Analog wormholes and black hole laser effects in hydrodynamics 

    Peloquin, C; Euvé, L-P; Philbin, T; Rousseaux, G (American Physical Society, 2016-04-18)
    We numerically study water wave packets on a spatially varying countercurrent in the presence of surface tension. Depending on the details of the velocity profile, we show that traversable and bidirectional analogue wormholes ...
  • Analysis of the sign-dependent switching observed in a hybrid aligned nematic cell 

    Cornford, Stephen Leslie; Taphouse, T. S.; Sambles, J. Roy (Institute of Physics and Deutsche Physikalische Gesellschaft, 2009)
    An optical waveguide experiment was used to study the influence of dc electric fields on a hybrid aligned nematic liquid crystal cell. This dc switching differed from ac switching in two ways: first, the equilibrium states ...
  • Analytical core mass function (CMF) from filaments: Under which circumstances can filament fragmentation reproduce the CMF? 

    Lee, Y-N; Hennebelle, P; Chabrier, G (American Astronomical Society / IOP Publishing, 2017-09-28)
    Observations suggest that star formation in filamentary molecular clouds occurs in a two-step process, with the formation of filaments preceding that of prestellar cores and stars. Here, we apply the gravo-turbulent ...
  • Analytical theory for the initial mass function: III time dependence and star formation rate 

    Hennebelle, P; Chabrier, G (American Astronomical Society, 2013-06-06)
    The present paper extends our previous theory of the stellar initial mass function (IMF) by including the time-dependence, and by including the impact of magnetic field. The predicted mass spectra are similar to the time ...
  • The ancient heritage of water ice in the solar system 

    Cleeves, L. Ilsedore; Bergin, Edwin A.; Alexander, Conel M. O’D.; Du, Fujun; Graninger, Dawn; Oberg, Karin I.; Harries, Tim J. (American Association for the Advancement of Science, 2014)
    Identifying the source of Earth's water is central to understanding the origins of life-fostering environments and to assessing the prevalence of such environments in space. Water throughout the solar system exhibits ...
  • Angle-independent microwave absorption by ultrathin microcavity arrays 

    Brown, James R.; Hibbins, Alastair P.; Lockyear, Matthew J.; Lawrence, Christopher R.; Sambles, J. Roy (American Institute of Physics, 2008)
    The resonant absorption of microwave radiation by thin, two-dimensional microcavity arrays has been studied. Resonant modes associated with these structures, formed from copper-clad FR4 laminates, exhibit both an azimuthal ...
  • Angular momentum evolution of young low-mass stars and brown dwarfs: observations and theory 

    Bouvier, Jerome; Matt, Sean P.; Mohanty, Subhanjoy; Scholz, Aleks; Stassun, Keivan G.; Zanni, Claudio (University of Arizona Press, 2014)
    This chapter aims at providing the most complete review of both the emerging concepts and the latest observational results regarding the angular momentum evolution of young low-mass stars and brown dwarfs. In the time since ...
  • Anharmonic effects in the thermoelectric properties of PbTe 

    Al-Otaibi, J; Srivastava, G.P. (American Institute of Physics (AIP), 2014-07-28)
    In this work, we investigate the crystal anharmonic effects in the thermoelectric properties of n-type PbTe. The lattice thermal transport coefficient is computed by employing an isotropic continuum model for the dispersion ...
  • Anisotropy, damping and coherence of magnetization dynamics in a 10 µm square Ni81Fe19 element 

    Barman, A.; Kruglyak, V.V.; Hicken, R.J.; Kundrotaite, A.; Rahman, M. (American Institute of Physics, 2003)
    We have studied magnetization precession in a square Ni81Fe19 element, of 10 μm width, by time-resolved scanning Kerr effect microscopy. From the frequency of precession, we deduce a fourfold in-plane anisotropy of about ...
  • Anomalous electromagnetic coupling via entanglement at the nanoscale 

    Slepyan, G; Boag, A; Mordachev, V; Sinkevich, E; Maksimenko, S; Kuzhir, P; Miano, G; Maffucci, A; Portnoi, ME (IOP Publishing for Deutsche Physikalische Gesellschaft, 2017-02-02)
    Understanding unwanted mutual interactions between devices at the nanoscale is crucial for the study of the electromagnetic compatibility in nanoelectronic and nanophotonic systems. Anomalous electromagnetic coupling ...
  • An anomalous extinction law in the Cep OB3b young cluster: Evidence for dust processing during gas dispersal 

    Allen, TS; Prchlik, JJ; Megeath, ST; Gutermuth, RA; Pipher, JL; Naylor, T; Jeffries, RD (American Astronomical Society, 2014-04-24)
    © 2014. The American Astronomical Society. All rights reserved. We determine the extinction law through Cep OB3b, a young cluster of 3000 stars undergoing gas dispersal. The extinction is measured toward 76 background K ...
  • Anyon exciton revisited 

    Parfitt, D.G.W.; Portnoi, M.E. (2003)
    We review the main results of the anyon exciton model in light of recent criticism by Wojs and Quinn. We show that the appearance of fractionally charged anyon ions at the bottom of their numerically calculated excitation ...
  • Anyon exciton revisited: Exact solutions for a few-particle system 

    Parfitt, D.G.W.; Portnoi, M.E. (American Physical Society, 2003)
    The anyon exciton model is generalized to the case of a neutral exciton consisting of a valence hole and an arbitrary number N of fractionally charged quasielectrons (anyons). A complete set of exciton basis functions is ...
  • Anyon excitons 

    Rashba, E.I.; Portnoi, M.E. (American Physical Society, 1993)
    We propose a model of an anyon exciton consisting of a hole and several anyons, and apply it to the spectroscopy of an incompressible quantum liquid. Fractionalization of the electron charge makes properties of such entities ...
  • The appropriate spatial resolution of future weather files for building simulation 

    Eames, M; Kershaw, T; Coley, D (Taylor & Francis, 2011-08-31)
    Building thermal modelling packages require weather data to predict representative internal conditions. Typically, around the world, reference weather years of various forms are used which are created from observations at ...
  • Architecture design study and technology roadmap for the Planet Formation Imager (PFI) 

    Monnier, JD; Ireland, MJ; Kraus, S; Baron, F; Creech-Eakman, M; Dong, R; Isella, A; Merand, A; Michael, E; Minardi, S; Mozurkewich, D; Petrov, R; Rinehard, S; ten Brummelaar, T; Vasisht, G; Wishnow, E; Young, J; Zhu, Z (Society of Photo-optical Instrumentation Engineers (SPIE), 2016-08-04)
    The Planet Formation Imager (PFI) Project has formed a Technical Working Group (TWG) to explore possible facility architectures to meet the primary PFI science goal of imaging planet formation in situ in nearby starforming ...
  • Are pre-main-sequence stars older than we thought? 

    Naylor, Tim (Oxford University Press / Royal Astronomical Society, 2009)
    We fit the colour–magnitude diagrams of stars between the zero-age main-sequence and terminal-age main sequence in young clusters and associations. The ages we derive are a factor of 1.5–2 longer than the commonly used ...
  • Are pre-MS stars older than we thought? 

    Naylor, T; Mayne, NJ (Cambridge University Press (CUP) for International Astronomical Union (IAU), 2010-10-21)
    We present a consistent age ordering for young clusters and groups determined using the contraction of stars through their pre-main-sequence phase. We compare these with ages derived from the evolution of the upper ...
  • Are turbulent spheres suitable initial conditions for star-forming clouds? 

    Rey-Raposo, Ramon; Dobbs, Clare; Duarte-Cabral, A. (Oxford University Press for Royal Astronomical Society, 2014)
    To date, most numerical simulations of molecular clouds, and star formation within them, assume a uniform density sphere or box with an imposed turbulent velocity field. In this work, we select molecular clouds from galactic ...
  • Arrangement of Photosystem II and ATP Synthase in Chloroplast Membranes of Spinach and Pea 

    Daum, B; Nicastro, D; Austin, J; McIntosh, JR; Kühlbrandt, W (American Society of Plant Biologists, 2010-04)
    We used cryoelectron tomography to reveal the arrangements of photosystem II (PSII) and ATP synthase in vitreous sections of intact chloroplasts and plunge-frozen suspensions of isolated thylakoid membranes. We found that ...