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  • Journal article
    Eastwood JP, Kataria DO, McInnes CR, Barnes NC, Mulligan Pet al., 2015,

    Sunjammer

    , WEATHER, Vol: 70, Pages: 27-30, ISSN: 0043-1656
  • Journal article
    Del Zanna L, Matteini L, Landi S, Verdini A, Velli Met al., 2015,

    Parametric decay of parallel and oblique Alfvén waves in the expanding solar wind

    , Journal of Plasma Physics, Vol: 81, ISSN: 0022-3778

    <jats:p>The long-term evolution of large-amplitude Alfvén waves propagating in the solar wind is investigated by performing two-dimensional MHD simulations within the expanding box model. The linear and nonlinear phases of the parametric decay instability are studied for both circularly polarized waves in parallel propagation and for arc-polarized waves in oblique propagation. The non-monochromatic case is also considered. In the oblique case, the direct excitation of daughter modes transverse to the local background field is found for the first time in an expanding environment, and this transverse cascade seems to be favored for monochromatic mother waves. The expansion effect reduces the instability growth rate, and it can even suppress its onset for the lowest frequency modes considered here, possibly explaining the persistence of these outgoing waves in the solar wind.</jats:p>
  • Journal article
    Sparks N, Toumi R, 2015,

    Numerical Simulations of Daytime Temperature and Humidity Crossover Effects in London

    , BOUNDARY-LAYER METEOROLOGY, Vol: 154, Pages: 101-117, ISSN: 0006-8314
  • Journal article
    Masters A, 2015,

    Magnetic reconnection at Neptune's magnetopause

    , JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 120, Pages: 479-493, ISSN: 2169-9380
  • Journal article
    Leitner S, Valavanoglou A, Brown P, Hagen C, Magnes W, Whiteside BJ, Carr CM, Delva M, Baumjohann Wet al., 2015,

    Design of the Magnetoresistive Magnetometer for ESA's SOSMAG Project

    , IEEE TRANSACTIONS ON MAGNETICS, Vol: 51, ISSN: 0018-9464
  • Book chapter
    Cargill P, 2015,

    Magnetic Reconnection in the Solar Corona: Historical Perspective and Modern Thinking

    , MAGNETOSPHERIC PLASMA PHYSICS: THE IMPACT OF JIM DUNGEY'S RESEARCH, Editors: Southwood, Cowley, Mitton, Publisher: SPRINGER, Pages: 221-251, ISBN: 978-3-319-18358-9
  • Journal article
    Sitch S, Friedlingstein P, Gruber N, Jones SD, Murray-Tortarolo G, Ahlstrom A, Doney SC, Graven H, Heinze C, Huntingford C, Levis S, Levy PE, Lomas M, Poulter B, Viovy N, Zaehle S, Zeng N, Arneth A, Bonan G, Bopp L, Canadell JG, Chevallier F, Ciais P, Ellis R, Gloor M, Peylin P, Piao SL, Le Quere C, Smith B, Zhu Z, Myneni Ret al., 2015,

    Recent trends and drivers of regional sources and sinks of carbon dioxide

    , BIOGEOSCIENCES, Vol: 12, Pages: 653-679, ISSN: 1726-4170
  • Journal article
    Mushtaq S, Steers EBM, Whitby JA, Horvath P, Michler J, Pickering JCet al., 2015,

    A glow discharge time-of-flight mass spectrometry (GD-TOFMS) study of the 'hydrogen effect' using copper, iron and titanium cathodes

    , JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, Vol: 30, Pages: 1774-1781, ISSN: 0267-9477
  • Book chapter
    Mitchell DG, Brandt PC, Carbary JF, Kurth WS, Krimigis SM, Paranicas C, Krupp N, Hamilton DC, Mauk BH, Hospodarsky GB, Dougherty MK, Pryor WRet al., 2015,

    Injection, Interchange, and Reconnection: Energetic Particle Observations in Saturn's Magnetosphere

    , MAGNETOTAILS IN THE SOLAR SYSTEM, Editors: Keiling, Jackman, Delamere, Publisher: BLACKWELL SCIENCE PUBL, Pages: 327-343, ISBN: 978-1-118-84234-8
  • Journal article
    Forsyth C, Watt CEJ, Rae IJ, Fazakerley AN, Kalmoni NME, Freeman MP, Boakes PD, Nakamura R, Dandouras I, Kistler LM, Jackman CM, Coxon JC, Carr CMet al., 2014,

    Increases in plasma sheet temperature with solar wind driving during substorm growth phases

    , GEOPHYSICAL RESEARCH LETTERS, Vol: 41, Pages: 8713-8721, ISSN: 0094-8276
  • Journal article
    Banks JR, Brindley HE, Hobby M, Marsham JHet al., 2014,

    The daytime cycle in dust aerosol direct radiative effects observed in the central Sahara during the Fennec campaign in June 2011

    , JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, Vol: 119, Pages: 13861-13876, ISSN: 2169-897X
  • Journal article
    Brown P, Whiteside BJ, Beek TJ, Fox P, Horbury TS, Oddy TM, Archer MO, Eastwood JP, Sanz-Hernndez D, Sample JG, Cupido E, O'Brien H, Carr CMet al., 2014,

    Space magnetometer based on an anisotropic magnetoresistive hybrid sensor

    , Review of Scientific Instruments, Vol: 85, ISSN: 1089-7623
  • Journal article
    Mistry R, Eastwood JP, Hietala H, 2014,

    Detection of small-scale folds at a solar wind reconnection exhaust

    , Journal of Geophysical Research: Space Physics, Vol: 120, Pages: 30-42, ISSN: 2169-9402

    Observations of reconnection in the solar wind over the last few years appear to indicate that the majority of large-scale reconnecting current sheets are roughly planar, and that reconnection itself is quasi-steady. Most studies of solar wind exhausts have used spacecraft with large separations and relatively low time cadence ion measurements. Here we present multipoint Cluster observations of a reconnection exhaust and the associated current sheet at ACE and Wind, enabling it to be studied on multiple length scales and at high time resolution. While analysis shows that on large scales the current sheet is planar, detailed measurements using the four closely spaced Cluster spacecraft show that the trailing edge of the reconnection jet is nonplanar with folds orthogonal to the reconnection plane, with length scales of approximately 230 ion inertial lengths. Our findings thus suggest that while solar wind current sheets undergoing reconnection may be planar on large scales, they may also exhibit complex smaller-scale structure. Such structure is difficult to observe and has rarely been detected because exhausts are rapidly convected past the spacecraft in a single cut; there is therefore a limited set of spacecraft trajectories through the exhaust which would allow the nonplanar features to be intercepted. We consider how such nonplanar reconnection current sheets can form and the processes which may have generated the 3-D structure that was observed.
  • Journal article
    Archer MO, Turner DL, Eastwood JP, Schwartz SJ, Horbury TSet al., 2014,

    Global impacts of a Foreshock Bubble: Magnetosheath, magnetopause and ground-based observations

    , Planetary and Space Science, Vol: 106, Pages: 56-66, ISSN: 1873-5088

    Using multipoint observations we show, for the first time, that Foreshock Bubbles (FBs) have a global impact on Earth׳s magnetosphere. We show that an FB, a transient kinetic phenomenon due to the interaction of backstreaming suprathermal ions with a discontinuity, modifies the total pressure upstream of the bow shock showing a decrease within the FB׳s core and sheath regions. Magnetosheath plasma is accelerated towards the intersection of the FB׳s current sheet with the bow shock resulting in fast, sunward, flows as well as outward motion of the magnetopause. Ground-based magnetometers also show signatures of this magnetopause motion simultaneously across at least 7 h of magnetic local time, corresponding to a distance of 21.5RE transverse to the Sun–Earth line along the magnetopause. These observed global impacts of the FB are in agreement with previous simulations and in stark contrast to the known localised, smaller scale effects of Hot Flow Anomalies (HFAs).
  • Journal article
    Den Hartog EA, Ruffoni MP, Lawler JE, Pickering JC, Lind K, Brewer NRet al., 2014,

    Fe I oscillator strengths for transitions from high-lying even-parity levels

    , Astrophysical Journal Supplement Series, Vol: 215, Pages: 1-13, ISSN: 0067-0049

    New radiative lifetimes, measured to ±5% accuracy, are reported for 31 even-parity levels of Fe I ranging from 45061 cm–1 to 56842 cm–1. These lifetimes have been measured using single-step and two-step time-resolved laser-induced fluorescence on a slow atomic beam of iron atoms. Branching fractions have been attempted for all of these levels, and completed for 20 levels. This set of levels represents an extension of the collaborative work reported in Ruffoni et al. The radiative lifetimes combined with the branching fractions yields new oscillator strengths for 203 lines of Fe I. Utilizing a 1D-LTE model of the solar photosphere, spectral syntheses for a subset of these lines which are unblended in the solar spectrum yields a mean iron abundance of langlog[ε(Fe)]rang = 7.45 ± 0.06.
  • Journal article
    Southwood D, 2014,

    Space science and policy

    , ASTRONOMY & GEOPHYSICS, Vol: 55, Pages: 26-32, ISSN: 1366-8781
  • Journal article
    Genestreti KJ, Fuselier SA, Goldstein J, Nagai T, Eastwood JPet al., 2014,

    The location and rate of occurrence of near-Earth magnetotail reconnection as observed by Cluster and Geotail

    , JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS, Vol: 121, Pages: 98-109, ISSN: 1364-6826
  • Journal article
    Qureshi MNS, Nasir W, Masood W, Yoon PH, Shah HA, Schwartz SJet al., 2014,

    Terrestrial lion roars and non-Maxwellian distribution

    , JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 119, ISSN: 2169-9380
  • Journal article
    Hunt GJ, Cowley SWH, Provan G, Bunce EJ, Alexeev II, Belenkaya ES, Kalegaev VV, Dougherty MK, Coates AJet al., 2014,

    Field-aligned currents in Saturn's southern nightside magnetosphere: Subcorotation and planetary period oscillation components

    , JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 119, ISSN: 2169-9380
  • Journal article
    Masters A, Achilleos N, Agnor CB, Campagnola S, Charnoz S, Christophe B, Coates AJ, Fletcher LN, Jones GH, Lamy L, Marzari F, Nettelmann N, Ruiz J, Ambrosi R, Andre N, Bhardwaj A, Fortney J, Hansen CJ, Helled R, Moragas-Klostermeyer G, Orton G, Ray L, Reynaud S, Sergis N, Srama R, Volwerk Met al., 2014,

    Neptune and Triton: Essential pieces of the Solar System puzzle

    , PLANETARY AND SPACE SCIENCE, Vol: 104, Pages: 108-121, ISSN: 0032-0633
  • Journal article
    Coustenis A, Atreya S, Castillo J, Coll P, Mueller-Wodarg I, Spilker Let al., 2014,

    Surfaces, atmospheres and magnetospheres of the outer planets and their satellites and ring systems: Part X Preface

    , PLANETARY AND SPACE SCIENCE, Vol: 104, Pages: 1-2, ISSN: 0032-0633
  • Journal article
    Balogh A, Hudson HS, Petrovay K, von Steiger Ret al., 2014,

    Introduction to the Solar Activity Cycle: Overview of Causes and Consequences

    , SPACE SCIENCE REVIEWS, Vol: 186, Pages: 1-15, ISSN: 0038-6308
  • Journal article
    Arridge CS, Achilleos N, Agarwal J, Agnor CB, Ambrosi R, Andre N, Badman SV, Baines K, Banfield D, Barthelemy M, Bisi MM, Blum J, Bocanegra-Bahamon T, Bonfond B, Bracken C, Brandt P, Briand C, Briois C, Brooks S, Castillo-Rogez J, Cavalie T, Christophe B, Coates AJ, Collinson G, Cooper JF, Costa-Sitja M, Courtin R, Daglis IA, De Pater I, Desai M, Dirkx D, Dougherty MK, Ebert RW, Filacchione G, Fletcher LN, Fortney J, Gerth I, Grassi D, Grodent D, Grun E, Gustin J, Hedman M, Helled R, Henri P, Hess S, Hillier JK, Hofstadter MH, Holme R, Horanyi M, Hospodarsky G, Hsu S, Irwin P, Jackman CM, Karatekin O, Kempf S, Khalisi E, Konstantinidis K, Kruger H, Kurth WS, Labrianidis C, Lainey V, Lamy LL, Laneuville M, Lucchesi D, Luntzer A, MacArthur J, Maier A, Masters A, McKenna-Lawlor S, Melin H, Milillo A, Moragas-Klostermeyer G, Morschhauser A, Moses JI, Mousis O, Nettelmann N, Neubauer FM, Nordheim T, Noyelles B, Orton GS, Owens M, Peron R, Plainaki C, Postberg F, Rambaux N, Retherford K, Reynaud S, Roussos E, Russell CT, Rymer A, Sallantin R, Sanchez-Lavega A, Santolik O, Saur J, Sayanagi K, Schenk P, Schubert J, Sergis N, Sittler EC, Smith A, Spahn F, Srama R, Stallard T, Sterken V, Sternovsky Z, Tiscareno M, Tobie G, Tosi F, Trieloff M, Turrini D, Turtle EP, Vinatier S, Wilson R, Zarkat Pet al., 2014,

    The science case for an orbital mission to Uranus: Exploring the origins and evolution of ice giant planets

    , PLANETARY AND SPACE SCIENCE, Vol: 104, Pages: 122-140, ISSN: 0032-0633
  • Journal article
    Chen CHK, Leung L, Boldyrev S, Maruca BA, Bale SDet al., 2014,

    Ion-scale spectral break of solar wind turbulence at high and low beta

    , GEOPHYSICAL RESEARCH LETTERS, Vol: 41, Pages: 8081-8088, ISSN: 0094-8276
  • Journal article
    Vigren E, Galand M, Yelle RV, Wellbrock A, Coates AJ, Snowden D, Cui J, Lavvas P, Edberg NJT, Shebanits O, Wahlund J-E, Vuitton V, Mandt Ket al., 2014,

    Ionization balance in Titan's nightside ionosphere

    , Icarus, Vol: 248, Pages: 539-546, ISSN: 0019-1035
  • Journal article
    Lacombe C, Alexandrova O, Matteini L, Santolik O, Cornilleau-Wehrlin N, Mangeney A, de Conchy Y, Maksimovic Met al., 2014,

    Whistler mode waves and the electron heat flux in the Solar wind: cluster observations

    , The Astrophysical Journal: an international review of astronomy and astronomical physics, Vol: 796, Pages: 1-11, ISSN: 0004-637X

    The nature of the magnetic field fluctuations in the solar wind between the ion and electron scales is still under debate. Using the Cluster/STAFF instrument, we make a survey of the power spectral density and of the polarization of these fluctuations at frequencies f in [1, 400] Hz, during five years (2001-2005), when Cluster was in the free solar wind. In ~10% of the selected data, we observe narrowband, right-handed, circularly polarized fluctuations, with wave vectors quasi-parallel to the mean magnetic field, superimposed on the spectrum of the permanent background turbulence. We interpret these coherent fluctuations as whistler mode waves. The lifetime of these waves varies between a few seconds and several hours. Here, we present, for the first time, an analysis of long-lived whistler waves, i.e., lasting more than five minutes. We find several necessary (but not sufficient) conditions for the observation of whistler waves, mainly a low level of background turbulence, a slow wind, a relatively large electron heat flux, and a low electron collision frequency. When the electron parallel beta factor β e∥ is larger than 3, the whistler waves are seen along the heat flux threshold of the whistler heat flux instability. The presence of such whistler waves confirms that the whistler heat flux instability contributes to the regulation of the solar wind heat flux, at least for β e∥ ≥ 3, in slow wind at 1 AU.
  • Journal article
    Weiss Z, Steers EBM, Pickering JC, Mushtaq Set al., 2014,

    Excitation and transition rate diagrams of singly ionized iron in analytical glow discharges in argon, neon and an argon-hydrogen mixture

    , JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, Vol: 29, Pages: 2078-2090, ISSN: 0267-9477
  • Journal article
    Ball WT, Krivova NA, Unruh YC, Haigh JD, Solanki SKet al., 2014,

    A new SATIRE-S spectral solar irradiance reconstruction for solar cycles 21-23 and its implications for stratospheric Ozone

    , Journal of the Atmospheric Sciences, Vol: 71, Pages: 4086-4101, ISSN: 0022-4928

    The authors present a revised and extended total and spectral solar irradiance (SSI) reconstruction, which includes a wavelength-dependent uncertainty estimate, spanning the last three solar cycles using the Spectral and Total Irradiance Reconstruction—Satellite era (SATIRE-S) model. The SSI reconstruction covers wavelengths between 115 and 160 000 nm and all dates between August 1974 and October 2009. This represents the first full-wavelength SATIRE-S reconstruction to cover the last three solar cycles without data gaps and with an uncertainty estimate. SATIRE-S is compared with the Naval Research Laboratory Spectral Solar Irradiance (NRLSSI) model and ultraviolet (UV) observations from the Solar Radiation and Climate Experiment (SORCE) Solar Stellar Irradiance Comparison Experiment (SOLSTICE). SATIRE-S displays similar cycle behavior to NRLSSI for wavelengths below 242 nm and almost twice the variability between 242 and 310 nm. During the decline of the last solar cycle, between 2003 and 2008, the SSI from SORCE SOLSTICE versions 12 and 10 typically displays more than 3 times the variability of SATIRE-S between 200 and 300 nm. All three datasets are used to model changes in stratospheric ozone within a 2D atmospheric model for a decline from high solar activity to solar minimum. The different flux changes result in different modeled ozone trends. Using NRLSSI leads to a decline in mesospheric ozone, while SATIRE-S and SORCE SOLSTICE result in an increase. Recent publications have highlighted increases in mesospheric ozone when considering version 10 SORCE SOLSTICE irradiances. The recalibrated SORCE SOLSTICE version 12 irradiances result in a much smaller mesospheric ozone response than that of version 10, and this smaller mesospheric ozone response is similar in magnitude to that of SATIRE-S. This shows that current knowledge of variations in spectral irradiance is not sufficient to warrant robust conclusions concerning the impact of solar variability on th
  • Journal article
    Mushtaq S, Steers EBM, Pickering JC, Smid Pet al., 2014,

    Enhancement of analyte atomic lines with excitation energies of about 5 eV in the presence of molecular gases in analytical glow discharges

    , JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, Vol: 29, Pages: 2022-2026, ISSN: 0267-9477
  • Journal article
    Mushtaq S, Steers EBM, Pickering JC, Weinstein Vet al., 2014,

    Effect of small quantities of oxygen in a neon glow discharge

    , JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, Vol: 29, Pages: 2027-2041, ISSN: 0267-9477

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