Now showing items 21-40 of 580

  • 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 ...
  • 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 ...
  • 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 ...
  • 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 ...
  • Assessing the risk of climate change for buildings: A comparison between multi-year and probabilistic reference year simulations 

    Kershaw, Tristan; Eames, Matthew E.; Coley, David (Elsevier, 2011)
    Given a changing climate, there is a need to provide data for future years so that practicing engineers can investigate the impact of climate change on particular designs and examine any risk the client might be exposed ...
  • Atmospheric escape from HD 189733b observed in H i Lyman-α: Detailed analysis of HST/STIS September 2011 observations 

    Bourrier, V.; Lecavelier des Etangs, A.; Dupuy, H.; Ehrenreich, D.; Vidal-Madjar, A.; Hebrard, G.; Ballester, G.; Desert, J.-M.; Ferlet, R.; Sing, David K.; Wheatley, P.J. (EDP Sciences for European Southern Observatory (ESO), 2013)
    Observations of transits of the hot giant exoplanet HD 189733b in the unresolved H i Lyman-α line show signs of hydrogen escaping the upper atmosphere of the planet. New resolved Lyman-α observations obtained with the STIS ...
  • Babinet’s principle and the band structure of surface waves on patterned metal arrays 

    Edmunds, James D.; Taylor, Melita C.; Hibbins, Alastair P.; Sambles, J. Roy; Youngs, I.J. (American Institute of Physics, 2010)
    The microwave response of an array of square metal patches and its complementary structure, an array of square holes, has been experimentally studied. The resonant phenomena, which yield either enhanced transmission or ...
  • Backflow in the relaxation of a hybrid aligned nematic cell 

    Jewell, Sharon A.; Sambles, J. Roy (American Institute of Physics, 2003)
    The optical convergent-beam technique has been used to measure the changing director profile in a 4.6 µm ZLI-2293 filled hybrid aligned nematic cell when a 7 Vrms ac voltage was removed. The relaxation process has been ...
  • Bayesian detection of planetary transits. A modified version of the Gregory-Loredo method for Bayesian periodic signal detection 

    Aigrain, Suzanne; Favata, F. (EDP Sciences, 2002)
    The detection of planetary transits in stellar photometric light-curves is poised to become the main method for finding substantial numbers of terrestrial planets. The French-European mission COROT (foreseen for launch in ...
  • Bioavailability of nanoscale metal oxides TiO(2), CeO(2), and ZnO to fish 

    Johnston, B.D.; Scown, Tessa M.; Moger, Julian; Cumberland, Susan A.; Baalousha, Mohamed; Linge, Kathryn; van Aerle, Ronny; Jarvis, Kym; Lead, Jamie R.; Tyler, Charles R. (American Chemical Society, 2010-02-01)
    Nanoparticles (NPs) are reported to be a potential environmental health hazard. For organisms living in the aquatic environment, there is uncertainty on exposure because of a lack of understanding and data regarding the ...
  • Black Hole Lasers Revisited 

    Leonhardt, Ulf; Philbin, Thomas G. (Springer, 2007)
    The production of Hawking radiation by a single horizon is not dependent on the high-frequency dispersion relation of the radiated field. When there are two horizons, however, Corley and Jacobson have shown that superluminal ...
  • Blue, surface-emitting, distributed feedback polyfluorene lasers 

    Heliotis, G.; Xia, R.; Bradley, D. D. C.; Turnbull, G. A.; Samuel, I. D. W.; Andrew, P.; Barnes, William L. (American Institute of Physics, 2003)
    We report the fabrication of optically-pumped solid-state distributed feedback lasers utilizing two blue-light-emitting semiconducting polyfluorenes as gain media. The lasers were readily fabricated by solution deposition ...
  • Broad-band polarization conversion from a finite periodic structure in the microwave regime 

    Hallam, B. T.; Lawrence, Christopher R.; Hooper, Ian R.; Sambles, J. Roy (American Institute of Physics, 2004)
    A reflection grating demonstrating extraordinarily broad-band polarization conversion in a nondiffractive regime has been studied at microwave frequencies. This single-element structure has been fabricated by electrolessly ...
  • Broadband and broadangle extraordinary acoustic transmission through subwavelength apertures surrounded by fluids 

    Carretero-Palacios, S.; Murray, Alasdair R.J.; Martín-Moreno, L.; Hibbins, Alastair P. (IOP Publishing for Deutsche Physikalische Gesellschaft, 2014)
    We present a mechanism for ultra-broadband transmission of acoustic waves through subwavelength hole arrays. Different fluids surrounding (or filling) the holes are considered, which allows tuning of the band of maximum ...
  • Broadband and low loss high refractive index metamaterials in the microwave regime 

    Campbell, T.; Hibbins, Alastair P.; Sambles, J. Roy; Hooper, Ian R. (American Institute of Physics, 2013)
    A broadband, low-loss, isotropic, high refractive index metamaterial comprising an array of close-packed cubic elements of cross-linked square metal plates is demonstrated in the microwave regime. The structuring of the ...
  • Broadband impedance-matched electromagnetic structured ferrite composite in the megahertz range 

    Parke, L.; Youngs, I.J.; Hibbins, Alastair P.; Sambles, J. Roy (American Institute of Physics (AIP), 2014)
    A high refractive-index structured ferrite composite is designed to experimentally demonstrate broadband impedance matching to free-space. It consists of an array of ferrite cubes that are anisotropically spaced, thereby ...