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  • Conference paper
    Daykin-Iliopoulos A, Desai R, 2014,

    Performance evaluation of micropropulsion systems with the application of Active Debris Removal

    Recent micropropulsion developments have increased the operational capabilities of microsatellites (< 100 kg), to the point where they are being considered for demanding missions such as Active Debris Removal (ADR). This study examines the state-of-the-art micropropulsion options that can be applied to a microsatellite performing a range of orbital manoeuvres such as ADR. To this end a generic system architecture is used for this example scenario with ranging delta-v requirements. A variety of propulsion systems are sized accordingly, and the trade-offs between the differing propulsion technologies evaluated with respect to the power requirements, System-Specific Impulse , and technology readiness level (TRL), as well as a ‘newly defined’ volume driven System-Specific Impulse . It was shown that the high specific impulse (> 2000s) and consequent mass and volume savings of miniaturised Electric Propulsion (EP) systems, such as the miniature ion and colloid thrusters, results in optimal ISSP’s and ISSP’s for the ADR scenario examined. Moreover an in-depth combined quantitative and qualitative analysis identifies delta-v regions most suited to both EP and Chemical Propulsion (CP) systems, as well as highlighting the inherent differences in the varying technologies with respect to volume as well as mass.
  • Journal article
    Alconcel LNS, Fox P, Brown P, Oddy TM, Lucek EL, Carr CMet al., 2014,

    An initial investigation of the long-term trends in the fluxgate magnetometer (FGM) calibration parameters on the four Cluster spacecraft

    , GEOSCIENTIFIC INSTRUMENTATION METHODS AND DATA SYSTEMS, Vol: 4, Pages: 43-84, ISSN: 2193-0856
  • Journal article
    Sheldon L, Czaja A, 2014,

    Seasonal and interannual variability of an index of deep atmospheric convection over western boundary currents

    , QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Vol: 140, Pages: 22-30, ISSN: 0035-9009
  • Journal article
    Beth A, Garnier P, Toublanc D, Dandouras I, Mazelle C, Kotova Aet al., 2014,

    Modeling the satellite particle population in the planetary exospheres: Application to Earth, Titan and Mars

    , Icarus, Vol: 227, Pages: 21-36, ISSN: 0019-1035
  • Journal article
    Masters A, Phan TD, Badman SV, Hasegawa H, Fujimoto M, Russell CT, Coates AJ, Dougherty MKet al., 2014,

    The plasma depletion layer in Saturn's magnetosheath

    , JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 119, Pages: 121-130, ISSN: 2169-9380
  • Journal article
    Weiss Z, Steers EBM, Pickering JC, Hoffmann V, Mushtaq Set al., 2014,

    Excitation of higher levels of singly charged copper ions in argon and neon glow discharges

    , JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, Vol: 29, Pages: 2256-2261, ISSN: 0267-9477
  • Conference paper
    Whiteside BJ, Brown P, Beek TJ, Horbury TS, Carr CMet al., 2014,

    TID Response of a Hybrid AMR Vector Magnetometer

    , IEEE Radiation Effects Data Workshop (REDW) is part of the Nuclear and Space Radiation Effect Conference (NSREC), Publisher: IEEE
  • Conference paper
    Fox N, Green P, Brindley H, Russell J, Smith D, Lobb D, Cutter M, Barnes Aet al., 2014,

    TRACEABLE RADIOMETRY UNDERPINNING TERRESTRIAL AND HELIO-STUDIES (TRUTHS): A BENCMARK MISSION FOR CLIMATE

    , International Conference on Space Optics (ICSO), Publisher: SPIE-INT SOC OPTICAL ENGINEERING, ISSN: 0277-786X
  • Book chapter
    Krasnoselskikh V, Balikhin M, Walker SN, Schwartz S, Sundkvist D, Lobzin V, Gedalin M, Bale SD, Mozer F, Soucek J, Hobara Y, Comisel Het al., 2014,

    The Dynamic Quasiperpendicular Shock: Cluster Discoveries

    , MICROPHYSICS OF COSMIC PLASMAS, Editors: Balogh, Bykov, Cargill, Dendy, DeWit, Raymond, Publisher: SPRINGER, Pages: 459-522, ISBN: 978-1-4899-7412-9
  • Book chapter
    Alexandrova O, Chen CHK, Sorriso-Valvo L, Horbury TS, Bale SDet al., 2014,

    Solar Wind Turbulence and the Role of Ion Instabilities

    , MICROPHYSICS OF COSMIC PLASMAS, Editors: Balogh, Bykov, Cargill, Dendy, DeWit, Raymond, Publisher: SPRINGER, Pages: 25-63, ISBN: 978-1-4899-7412-9
  • Journal article
    Nakamura R, Plaschke F, Teubenbacher R, Giner L, Baumjohann W, Magnes W, Steller M, Torbert RB, Vaith H, Chutter M, Fornacon K-H, Glassmeier K-H, Carr Cet al., 2014,

    Interinstrument calibration using magnetic field data from the flux-gate magnetometer (FGM) and electron drift instrument (EDI) onboard Cluster

    , GEOSCIENTIFIC INSTRUMENTATION METHODS AND DATA SYSTEMS, Vol: 3, Pages: 1-11, ISSN: 2193-0856
  • Book chapter
    Ghavamian P, Schwartz SJ, Mitchell J, Masters A, Laming JMet al., 2014,

    Electron-Ion Temperature Equilibration in Collisionless Shocks: The Supernova Remnant-Solar Wind Connection

    , MICROPHYSICS OF COSMIC PLASMAS, Editors: Balogh, Bykov, Cargill, Dendy, DeWit, Raymond, Publisher: SPRINGER, Pages: 557-587, ISBN: 978-1-4899-7412-9
  • Book chapter
    Schwartz SJ, Zweibel EG, Goldman M, 2014,

    Microphysics in Astrophysical Plasmas

    , MICROPHYSICS OF COSMIC PLASMAS, Editors: Balogh, Bykov, Cargill, Dendy, DeWit, Raymond, Publisher: SPRINGER, Pages: 5-23, ISBN: 978-1-4899-7412-9
  • Book chapter
    Mueller-Wodarg ICF, Griffith CA, Lellouch E, Cravens TEet al., 2014,

    TITAN Interior, Surface, Atmosphere, and Space Environment Introduction

    , TITAN: INTERIOR, SURFACE, ATMOSPHERE, AND SPACE ENVIRONMENT, Editors: MullerWodarg, Griffith, Lellouch, Cravens, Publisher: CAMBRIDGE UNIV PRESS, Pages: 1-9
  • Journal article
    O'Connor FM, Johnson CE, Morgenstern O, Abraham NL, Braesicke P, Dalvi M, Folberth GA, Sanderson MG, Telford PJ, Voulgarakis A, Young PJ, Zeng G, Collins WJ, Pyle JAet al., 2014,

    Evaluation of the new UKCA climate-composition model - Part 2: The Troposphere

    , GEOSCIENTIFIC MODEL DEVELOPMENT, Vol: 7, Pages: 41-91, ISSN: 1991-959X
  • Book chapter
    Balogh A, Bykov A, Cargill P, Dendy R, de Wit TD, Raymond Jet al., 2014,

    Microphysics of Cosmic Plasmas: Background, Motivation and Objectives

    , MICROPHYSICS OF COSMIC PLASMAS, Editors: Balogh, Bykov, Cargill, Dendy, DeWit, Raymond, Publisher: SPRINGER, Pages: 1-4, ISBN: 978-1-4899-7412-9
  • Journal article
    Mushtaq S, Steers EBM, Pickering JC, Putyera Ket al., 2013,

    Selective and non-selective excitation/ionization processes in analytical glow discharges: excitation of the ionic spectra in argon/helium mixed plasmas

    , Journal of Analytical Atomic Spectrometry

    The increasing use of mixed gases, including helium mixtures, in glow discharge mass spectrometry has led to a need to understand the resulting signal enhancements due to changes in excitation and ionization processes. To understand more fully these processes in glow discharge, we have carried out complementary optical emission spectrometry experiments. The presence of added gases in the plasma gas can cause major changes in the number density of plasma gas ions and metastable atoms and so affects the intensities of spectral lines involving selective and non-selective excitation & ionization processes. We report the results of an experimental investigation on the effect of Ar/He mixed plasmas on the relative emission intensities of various analyte materials including copper, iron and titanium. Selective and non-selective excitation processes which are mainly dependent on the nature of the plasma gas and analyte material are observed and discussed.
  • Journal article
    Ruffoni MP, Allende Prieto C, Nave G, Pickering JCet al., 2013,

    INFRARED LABORATORY OSCILLATOR STRENGTHS OF Fe I IN THE <i>H</i>-BAND

    , ASTROPHYSICAL JOURNAL, Vol: 779, ISSN: 0004-637X
  • Journal article
    Maruca BA, Bale SD, Sorriso-Valvo L, Kasper JC, Stevens MLet al., 2013,

    Collisional Thermalization of Hydrogen and Helium in Solar-Wind Plasma

    , PHYSICAL REVIEW LETTERS, Vol: 111, ISSN: 0031-9007
  • Journal article
    Hietala H, Plaschke F, 2013,

    On the generation of magnetosheath high-speed jets by bow shock ripples

    , Journal of Geophysical Research: Space Physics, Vol: 118, Pages: 7237-7245, ISSN: 2169-9380

    [1] The terrestrial magnetosheath is embedded with coherent high‒speed jets of about 1RE in scale, predominantly during quasi‒radial interplanetary magnetic field (IMF). When these high dynamic pressure (Pdyn) jets hit the magnetopause, they cause large indentations and further magnetospheric effects. The source of these jets has remained controversial. One of the proposed mechanisms is based on ripples of the quasi‒parallel bow shock. In this paper, we combine for the first time, 4 years of subsolar magnetosheath observations from the Time History of Events and Macroscale Interactions during Substorms mission and corresponding NASA/OMNI solar wind conditions with model calculations of a rippled bow shock. Concentrating on the magnetosheath close to the shock during intervals when the angle between the IMF and the Sun‒Earth line was small, we find that (1) 97% of the observed jets can be produced by local ripples of the shock under the observed upstream conditions; (2) the coherent jets form a significant fraction of the high Pdyn tail of the magnetosheath flow distribution; (3) the magnetosheath Pdyn distribution matches the flow from a bow shock with ripples that have a dominant amplitude to wavelength ratio of about 9% (∼0.1RE/1RE) and are present ∼12% of the time at any given location.
  • Journal article
    Mozer FS, Bale SD, Bonnell JW, Chaston CC, Roth I, Wygant Jet al., 2013,

    Megavolt Parallel Potentials Arising from Double-Layer Streams in the Earth's Outer Radiation Belt

    , PHYSICAL REVIEW LETTERS, Vol: 111, ISSN: 0031-9007
  • Conference paper
    Fox C, Pickering JC, Beeby R, Murray JE, Last A, Green PDet al., 2013,

    Studies of the far IR water vapour continuum from CAVIAR and RHUBC campaigns using TAFTS

    We report results from the participation of the Imperial College TAFTS instrument in the CAVIAR and RHUBC field campaigns, validating a derived water vapor continuum parameterization in the far-IR spectral region. © OSA 2013.
  • Conference paper
    Pickering JC, Ruffoni M, Liggins F, Thorne APet al., 2013,

    Accurate laboratory atomic and molecular data for astrophysics applications by high resolution Fourier transform spectrometry

    Accurate high resolution atomic and molecular data are required for interpretation of many astrophysical spectra. The Imperial College London laboratory astrophysics program using high resolution Fourier Transform spectrometry is described. © 2013 Optical Society of America.
  • Conference paper
    Fox C, Pickering JC, Beeby R, Murray JE, Last A, Green PDet al., 2013,

    Studies of the far IR water vapour continuum from CAVIAR and RHUBC campaigns using TAFTS

    We report results from the participation of the Imperial College TAFTS instrument in the CAVIAR and RHUBC field campaigns, validating a derived water vapor continuum parameterization in the far-IR spectral region. © OSA 2013.
  • Conference paper
    Fox C, Pickering JC, Beeby R, Murray JE, Last A, Green PDet al., 2013,

    Studies of the far IR water vapour continuum from CAVIAR and RHUBC campaigns using TAFTS

    We report results from the participation of the Imperial College TAFTS instrument in the CAVIAR and RHUBC field campaigns, validating a derived water vapor continuum parameterization in the far-IR spectral region. © OSA 2013.
  • Journal article
    Mitchell JJ, Schwartz SJ, 2013,

    Nonlocal electron heating at the Earth's bow shock and the role of the magnetically tangent point

    , JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 118, Pages: 7566-7575, ISSN: 2169-9380
  • Journal article
    Masters A, Stawarz L, Fujimoto M, Schwartz SJ, Sergis N, Thomsen MF, Retino A, Hasegawa H, Zieger B, Lewis GR, Coates AJ, Canu P, Dougherty MKet al., 2013,

    <i>In situ</i> observations of high-Mach number collisionless shocks in space plasmas

    , PLASMA PHYSICS AND CONTROLLED FUSION, Vol: 55, ISSN: 0741-3335
  • Journal article
    Eastwood JP, Phan TD, Oieroset M, Shay MA, Malakit K, Swisdak M, Drake JF, Masters Aet al., 2013,

    Influence of asymmetries and guide fields on the magnetic reconnection diffusion region in collisionless space plasmas

    , PLASMA PHYSICS AND CONTROLLED FUSION, Vol: 55, ISSN: 0741-3335
  • Journal article
    Franci L, De Pietri R, Dionysopoulou K, Rezzolla Let al., 2013,

    Dynamical bar-mode instability in rotating and magnetized relativistic stars

    , PHYSICAL REVIEW D, Vol: 88, ISSN: 1550-7998
  • Journal article
    Pudney MA, Carr CM, Schwartz SJ, Howarth SIet al., 2013,

    Near-magnetic-field scaling for verification of spacecraft equipment

    , Geoscientific Instrumentation, Methods and Data Systems, Vol: 2, Pages: 249-255, ISSN: 2193-0864

    Magnetic-field measurements are essential tothe success of many scientific space missions. Outside ofthe earth’s magnetic field the biggest potential source ofmagnetic-field contamination of these measurements is emittedby the spacecraft. Spacecraft magnetic cleanliness is enforcedthrough the application of strict ground verificationrequirements for spacecraft equipment and instruments. Dueto increasingly strict AC magnetic-field requirements, manyspacecraft units cannot be verified on the ground using existingtechniques. These measurements must instead be takenclose to the equipment under test (EUT) and then extrapolated.A traditional dipole power law of −3 (with a fieldfall-off proportional to r−3) cannot be applied at these closedistances without risk of underestimating the field emitted bythe EUT, but we demonstrate that a power law of −2 is tooconservative. We propose a compromise that uses a powerlaw of −2 up to a distance equal to 3 times the unit size, beyondwhich a dipole power law can be applied. When extrapolatingfrom a distance of 0.20 m to 1.00 m from the centre ofa 0.20 m wide EUT, we demonstrate that this method avoidsan under prediction of the field, and is at least twice as accurateas performing the extrapolation with a fixed power lawof −2.

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

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