Publications

2021

In situ observations of ions and magnetic field around Phobos: the mass spectrum analyzer (MSA) for the Martian Moons eXploration (MMX) mission
- Yokota Shoichiro
- Terada Naoki
- Matsuoka Ayako
- Murata Naofumi
- Saito Yoshifumi
- Delcourt Dominique
- Futaana Yoshifumi
- Seki Kanako
- Schaible Micah J
- Asamura Kazushi
- Kasahara Satoshi
- Nakagawa Hiromu
- Nishino Masaki N.
- Nomura Reiko
- Keika Kunihiro
- Harada Yuki
- Imajo Shun
Earth Planets and Space, Springer / Terra Scientific Publishing Company, 2021, 73 (1), pp.216. The mass spectrum analyzer (MSA) will perform in situ observations of ions and magnetic fields around Phobos as part of the Martian Moons eXploration (MMX) mission to investigate the origin of the Martian moons and physical processes in the Martian environment. MSA consists of an ion energy mass spectrometer and two magnetometers which will measure velocity distribution functions and mass/charge distributions of low-energy ions and magnetic field vectors, respectively. For the MMX scientific objectives, MSA will observe solar wind ions, those scattered at the Phobos surface, water-related ions generated in the predicted Martian gas torus, secondary ions sputtered from Phobos, and escaping ions from the Martian atmosphere, while monitoring the surrounding magnetic field. MSA will be developed from previous instruments for space plasma missions such as Kaguya, Arase, and BepiColombo/Mio to contribute to the MMX scientific objectives. (10.1186/s40623-021-01452-x)
DOI : 10.1186/s40623-021-01452-x
Re‐analysis of the Cassini RPWS/LP data in Titan’s ionosphere. Part I: detection of several electron populations
- Chatain Audrey
- Wahlund J.-E.
- Shebanits O.
- Hadid L. Z.
- Morooka M.
- Edberg N. J. T.
- Guaitella O.
- Carrasco Nathalie
Journal of Geophysical Research Space Physics, American Geophysical Union/Wiley, 2021, 126 (8), pp.e2020JA028412. Current models of Titan's ionosphere have difficulties in explaining the observed electron density and/or temperature. In order to get new insights, we re-analyzed the data taken in the ionosphere of Titan by the Cassini Langmuir probe (LP), part of the Radio and Plasma Wave Science (RPWS) instrument. This is the first of two papers that present the new analysis method (current paper) and statistics on the whole dataset. We suggest that between 2 and 4 electron populations are necessary to fit the data. Each population is defined by a potential, an electron density and an electron temperature and is easily visualized by a dinstinct peak in the second derivative of the electron current, which is physically related to the electron energy distribution function (Druyvesteyn method). The detected populations vary with solar illumination and altitude. We suggest that the 4 electron populations are due to photo-ionization, magnetospheric particles, dusty plasma and electron emission from the probe boom, respectively. (10.1029/2020JA028412)
DOI : 10.1029/2020JA028412
Re-analysis of the Cassini RPWS/LP data in Titan's ionosphere. Part II: statistics on 57 flybys
- Chatain Audrey
- Wahlund J.-E.
- Shebanits O.
- Hadid L. Z.
- Morooka M.
- Edberg N. J. T.
- Guaitella O.
- Carrasco Nathalie
Journal of Geophysical Research Space Physics, American Geophysical Union/Wiley, 2021, 126 (8), pp.e2020JA028413. The ionosphere of Titan hosts a complex ion chemistry leading to the formation of organic dust below 1200 km. Current models cannot fully explain the observed electron temperature in this dusty environment. To achieve new insight, we have re-analyzed the data taken in the ionosphere of Titan by the Cassini Langmuir probe (LP), part of the Radio and Plasma Wave Science package. A first paper (Chatain et al., n.d.) introduces the new analysis method and discusses the identification of 4 electron populations produced by different ionization mechanisms. In this second paper, we present a statistical study of the whole LP dataset below 1200 km which gives clues on the origin of the 4 populations. One small population is attributed to photo- or secondary electrons emitted from the surface of the probe boom. A second population is systematically observed, at a constant density (∼500 cm-3), and is attributed to background thermalized electrons from the ionization process of precipitating particles fom the surrounding magnetosphere. The two last populations increase in density with pressure, solar illumination and EUV flux. The third population is observed with varying densities at all altitudes and solar zenith angles except on the far nightside (SZA > ∼140°), with a maximum density of 2700 cm-3. It is therefore certainly related to the photo-ionization of the atmospheric molecules. Finally, a fourth population detected only on the dayside and below 1200 km reaching up to 2000 cm-3 could be photo- or thermo-emitted from dust grains. (10.1029/2020JA028413)
DOI : 10.1029/2020JA028413
Saddle-shaped Solar Flare Arcades
- Lörinčík Juraj
- Dudík Jaroslav
- Aulanier Guillaume
The Astrophysical Journal Letters, Bristol : IOP Publishing, 2021, 909 (1), pp.L4. Arcades of flare loops form as a consequence of magnetic reconnection powering solar flares and eruptions. We analyze the morphology and evolution of flare arcades that formed during five well-known eruptive flares. We show that the arcades have a common saddle-like shape. The saddles occur despite the fact that the flares were of different classes (C to X), occurred in different magnetic environments, and were observed in various projections. The saddles are related to the presence of longer, relatively higher, and inclined flare loops, consistently observed at the ends of the arcades, which we term "cantles." Our observations indicate that cantles typically join straight portions of flare ribbons with hooked extensions of the conjugate ribbons. The origin of the cantles is investigated in stereoscopic observations of the 2011 May 9 eruptive flare carried out by the Atmospheric Imaging Assembly and Extreme Ultraviolet Imager. The mutual separation of the instruments led to ideal observational conditions allowing for simultaneous analysis of the evolving cantle and the underlying ribbon hook. Based on our analysis we suggest that the formation of one of the cantles can be explained by magnetic reconnection between the erupting structure and its overlying arcades. We propose that the morphology of flare arcades can provide information about the reconnection geometries in which the individual flare loops originate. (10.3847/2041-8213/abe7f7)
DOI : 10.3847/2041-8213/abe7f7
Fast-ion pressure dominating the mass dependence of the core heat transport in ASDEX Upgrade H-modes
- Schneider P.A.
- Bonanomi N.
- Angioni C.
- Weiland M.
- Cavedon M.
- David P.
- Fischer R.
- Hennequin Pascale
- Hobirk J.
- Kappatou A.
- Kurzan B.
- Mcdermott R.M.
- Plank U.
- Pütterich T.
- Ryter F.
- Willensdorfer M.
Nuclear Fusion, IOP Publishing, 2021, 61 (3), pp.036033. H-mode plasmas in ASDEX Upgrade (AUG) using different hydrogen isotopes are analysed with respect to their core transport properties. The experimental results are discussed and we present gyrokinetic simulations which are able to reproduce the experimental observations. A novel strategy allows us to disentangle core and pedestal physics by mitigating the isotopic dependence of pedestal properties while keeping the heat and particle sources the same. Matched pedestal profiles are obtained between hydrogen (H) and deuterium (D) plasmas when increasing the triangularity in H plasmas with respect to D plasmas. In the core of these plasmas little isotopic dependence is observed when the fast-ion content is low Wfast/Wth < 1/3. Quasi-linear modelling with TGLF reproduces the experimental trends under these conditions. For larger fast-ion fractions an isotope dependence is observed in the core heat transport. This is related to a difference in fast-ion stabilization of turbulent transport. The fast-ion pressure in H and D plasmas is different due to the mass dependence in the fast-ion slowing down time as well as to operational restrictions when heating with H neutral beam injection (H-NBI) or D-NBI. Typically, Wfast,H < 1/2Wfast,D for comparable NBI heating powers in AUG. The gyrokinetic analysis shows that linear growth rates of ITG modes do not show a pure gyro-Bohm mass dependence, but follow the experimentally observed mass dependence when taking collisions, EM-effects and fast ions into account. Non-linear gyrokinetic simulations reproduce the experimental heat fluxes for different isotopes when fast ions are included. This highlights the role of the fast-ion pressure as a key element to explain the observed differences in the core of H and D plasmas. (10.1088/1741-4326/abd95e)
DOI : 10.1088/1741-4326/abd95e
Direct Evidence of a Dual Cascade in Gravitational Wave Turbulence
- Galtier Sebastien
- Nazarenko Sergey V.
Physical Review Letters, American Physical Society, 2021, 127 (13), pp.131101. We present the first direct numerical simulation of gravitational wave turbulence. General relativity equations are solved numerically in a periodic box with a diagonal metric tensor depending on two space coordinates only, <math display="inline"><msub><mi>g</mi><mrow><mi>i</mi><mi>j</mi></mrow></msub><mo>≡</mo><msub><mi>g</mi><mrow><mi>i</mi><mi>i</mi></mrow></msub><mo stretchy="false">(</mo><mi>x</mi><mo>,</mo><mi>y</mi><mo>,</mo><mi>t</mi><mo stretchy="false">)</mo><msub><mi>δ</mi><mrow><mi>i</mi><mi>j</mi></mrow></msub></math>, and with an additional small-scale dissipative term. We limit ourselves to weak gravitational waves and to a freely decaying turbulence. We find that an initial metric excitation at intermediate wave number leads to a dual cascade of energy and wave action. When the direct energy cascade reaches the dissipative scales, a transition is observed in the temporal evolution of energy from a plateau to a power-law decay, while the inverse cascade front continues to propagate toward low wave numbers. The wave number and frequency-wave-number spectra are found to be compatible with the theory of weak wave turbulence and the characteristic timescale of the dual cascade is that expected for four-wave resonant interactions. The simulation reveals that an initially weak gravitational wave turbulence tends to become strong as the inverse cascade of wave action progresses with a selective amplification of the fluctuations <math display="inline"><msub><mi>g</mi><mn>11</mn></msub></math> and <math display="inline"><msub><mi>g</mi><mn>22</mn></msub></math>. (10.1103/PhysRevLett.127.131101)
DOI : 10.1103/PhysRevLett.127.131101
Energetic ions in the Venusian system: Insights from the first Solar Orbiter flyby
- Allen R. C.
- Cernuda I.
- Pacheco D.
- Berger L.
- Xu Z. G.
- Freiherr von Forstner J. L.
- Rodríguez-Pacheco J.
- Wimmer-Schweingruber R. F.
- Ho G. C.
- Mason G. M.
- Vines S. K.
- Khotyaintsev Y.
- Horbury T.
- Maksimovic M.
- Hadid L. Z.
- Volwerk M.
- Dimmock A. P.
- Sorriso-Valvo L.
- Stergiopoulou K.
- Andrews G. B.
- Angelini V.
- Bale S. D.
- Boden S.
- Böttcher S. I.
- Chust T.
- Eldrum S.
- Espada P. P.
- Espinosa Lara F.
- Evans V.
- Gómez-Herrero R.
- Hayes J. R.
- Hellín A. M.
- Kollhoff A.
- Krasnoselskikh V.
- Kretzschmar Matthieu
- Kühl P.
- Kulkarni S. R.
- Lees W. J.
- Lorfèvre E.
- Martin C.
- O'Brien H.
- Plettemeier D.
- Polo O. R.
- Prieto M.
- Ravanbakhsh A.
- Sánchez-Prieto S.
- Schlemm C. E.
- Seifert H.
- Souček J.
- Steller M.
- Štverák Š.
- Terasa J. C.
- Trávníček P.
- Tyagi K.
- Vaivads A.
- Vecchio A.
- Yedla M.
Astronomy & Astrophysics - A&A, EDP Sciences, 2021, 656, pp.11 pp.. The Solar Orbiter flyby of Venus on 27 December 2020 allowed for an opportunity to measure the suprathermal to energetic ions in the Venusian system over a large range of radial distances to better understand the acceleration processes within the system and provide a characterization of galactic cosmic rays near the planet. Bursty suprathermal ion enhancements (up to ∼10 keV) were observed as far as ∼50RV downtail. These enhancements are likely related to a combination of acceleration mechanisms in regions of strong turbulence, current sheet crossings, and boundary layer crossings, with a possible instance of ion heating due to ion cyclotron waves within the Venusian tail. Upstream of the planet, suprathermal ions are observed that might be related to pick-up acceleration of photoionized exospheric populations as far as 5RV upstream in the solar wind as has been observed before by missions such as Pioneer Venus Orbiter and Venus Express. Near the closest approach of Solar Orbiter, the Galactic cosmic ray (GCR) count rate was observed to decrease by approximately 5 percent, which is consistent with the amount of sky obscured by the planet, suggesting a negligible abundance of GCR albedo particles at over 2 RV. Along with modulation of the GCR population very close to Venus, the Solar Orbiter observations show that the Venusian system, even far from the planet, can be an effective accelerator of ions up to ∼30 keV. This paper is part of a series of the first papers from the Solar Orbiter Venus flyby. (10.1051/0004-6361/202140803)
DOI : 10.1051/0004-6361/202140803
Latest experimental and theoretical advances in the production of negative ions in caesium-free plasmas
- Taccogna F.
- Béchu S.
- Aanesland A.
- Agostinetti P.
- Agnello R.
- Aleiferis S.
- Angot T.
- Antoni V.
- Bacal M.
- Barbisan M.
- Bentounes J.
- Bès A.
- Capitelli M.
- Cartry G.
- Cavenago M.
- Celiberto R.
- Chitarin G.
- Delogu R.
- de Lorenzi A.
- Esposito F.
- Fadone M.
- Ferron N.
- Fubiani G.
- Furno I.
- Gavilan L.
- Guittienne P.
- Howling A.
- Jacquier R.
- Laricchiuta A.
- Layet J.M. M
- Lemaire J.L. L
- Longo S.
- Maurice B.
- Minelli P.
- Minissale M.
- Mitrou M.
- Moussaoui R.
- Pimazzoni A.
- Poggi C.
- Rafalskyi D.
- Salomon E.
- Sartori E.
- Sasao M.
- Serianni G.
- Spada E.
- Suweis S.
- Svarnas P.
- Tahri L.
- Ugoletti M.
- Variale V.
- Veltri P.
The European Physical Journal D : Atomic, molecular, optical and plasma physics, EDP Sciences, 2021, 75 (8), pp.227. This topical review gathers the last updates concerning caesium-free negative ion sources presented during the $63{\mathrm {rd}}$ Course of the International school of Quantum Electronics of the Ettore Majorana Foundation and European collaborative works related to these lectures. Hence, beyond the frame of this course this topical review addresses both theoretical and experimental work performed during these last few years and complexities represented by the conception of a negative ion source ranging from the creation of negative ions to their neutralization.[graphic not available: see fulltext][graphic not available: see fulltext] (10.1140/epjd/s10053-021-00228-y)
DOI : 10.1140/epjd/s10053-021-00228-y
Automated Multi-Dataset Analysis (AMDA): An on-line database and analysis tool for heliospheric and planetary plasma data
- Génot Vincent
- Budnik E.
- Jacquey C.
- Bouchemit M.
- Renard B.
- Dufourg N.
- André N.
- Cecconi Baptiste
- Hadj Mohand H. Si
- Tao C.
- Besson B.
- Heulet D.
- Boucon D.
- Durand J.
- Bourrel N.
- Brzustowski Q.
- Jourdane N.
- Hitier R.
- Garnier P.
- Grison B.
- Aunai N.
- Jeandet A.
- Cabrolie F.
Planetary and Space Science, Elsevier, 2021, 201, pp.105214. Accessing, visualizing and analyzing heterogeneous plasma datasets has always been a tedious task that hindered students and senior researchers as well. Offering user friendly and versatile tools to perform basic research tasks is therefore pivotal for data centres including the Centre de Données de la Physique des Plasmas (CDPP http://www.cdpp.eu/) which holds a large variety of plasma data from various Earth, planetary and heliophysics missions and observatories in plasma physics. This clearly helps gaining increased attention, relevant feedback, and enhanced science return on data. These are the key ideas that crystallized at CDPP more than 15 years ago and resulted in the lay-out of the concepts, and then development, of AMDA, the Automated Multi-Dataset Analysis software (http://amda.cdpp.eu/). This paper gives a description of the architecture of AMDA, describes its functionalities, presents some use cases taken from the literature or fruitful collaborations and shows how it offers unique capabilities for educational purposes. (10.1016/j.pss.2021.105214)
DOI : 10.1016/j.pss.2021.105214
Comparison of ionospheric anomalies over African equatorial/low-latitude region with IRI-2016 model predictions during the maximum phase of solar cycle 24
- Amaechi Paul O
- Oyeyemi Elijah O
- Akala Andrew O
- Kaab Mohamed
- Younas Waqar
- Benkhaldoun Zouhair
- Khan Majid
- Mazaudier Christine-Amory
Advances in Space Research, Elsevier, 2021, 68 (3), pp.1473-1484. The capability of IRI-2016 in reproducing the hemispheric asymmetry, the winter and semiannual anomalies has been assessed over the equatorial ionization anomaly (EIA) during quiet periods of years 2013–2014. The EIA reconstructed using Total Electron Content (TEC) derived from Global Navigation Satellite System was compared with that computed using IRI-2016 along longitude 25° − 40oE. These were analyzed along with hemispheric changes in the neutral wind derived from the horizontal wind model and the TIMED GUVI columnar O/N2 data. IRI-2016 clearly captured the hemispheric asymmetry of the anomaly during all seasons albeit with some discrepancies in the magnitude and location of the crests. The winter anomaly in TEC which corresponded with greater O/N2 in the winter hemisphere was also predicted by IRI-2016 during December solstice. The model also captured the semiannual anomaly with stronger crests in the northern hemisphere. Furthermore, it reproduced the variation trend of the asymmetry index (A) in December solstice and equinox during noon. However, in June solstice the model failed to capture the winter anomaly and misrepresented the variation of A. This was linked with its inability to accurately predict the pattern of the neutral wind, the maximum height of the F2 layer and the changes in O/N2 in both hemispheres. The difference between the variations of EUV and F10.7 fluxes was also a potential source of errors in IRI-2016. The results highlight the significance of the inclusion of wind data in IRI-2016 in order to enhance its performance over East Africa. (10.1016/j.asr.2021.03.040)
DOI : 10.1016/j.asr.2021.03.040
Secondary electron emission due to multi-species iodine ion bombardment of different target materials
- Habl L.
- Rafalskyi D.
- Lafleur T.
Journal of Applied Physics, American Institute of Physics, 2021, 129 (15), pp.153302. Ion-induced Secondary Electron Emission (SEE) is a fundamental surface interaction that strongly influences many plasma discharges. Recently, interest in iodine plasmas is growing due to new material processing and space propulsion applications, but data for SEE yields due to iodine ion bombardment remains scarce. Additionally, due to the formation of multiple ion species in typical iodine plasmas, and surface chemical reactions leading to iodide layer formation, the effective SEE yield is expected to differ from that for individual ion species on clean surfaces. In this work, we measure the SEE yield of multi-species iodine ion beams bombarding different target materials (Mo, W, Al, Ti, Cu, carbon-carbon, and steel), in the energy range 0.6-1.4 keV. An ion beam is produced by extracting and accelerating ions from a gridded ion source based on an Inductively Coupled Plasma (ICP). SEE yields of downstream targets are measured using a conventional electrostatic probe technique, and the ion beam composition is determined using time-of-flight spectrometry. The beam is composed predominately of atomic (I +) and molecular (I + 2) ions whose ratio changes depending on the ICP power. Yields depend strongly on the target material and beam composition, and vary between 0.05-0.4 depending on whether potential or kinetic emission processes dominate. (10.1063/5.0048447)
DOI : 10.1063/5.0048447
Poloidally resolved measurements of the perpendicular propagation velocity of density fluctuations in ASDEX Upgrade L-mode plasmas
- Höfler K
- Happel T
- Hennequin Pascale
- Stroth U
- Cavedon M
- Dux R
- Fischer R
- Mcdermott R
- Poli E
- Schuster C
- Wolfrum E
Plasma Physics and Controlled Fusion, IOP Publishing, 2021, 63 (3), pp.035020. Poloidal asymmetries of the propagation velocity of density fluctuations perpendicular to the magnetic field measured with Doppler reflectometry have been reported in several magnetic confinement plasma devices. Careful analysis of a large variety of different low confinement mode plasma scenarios performed at the ASDEX Upgrade tokamak does not reveal such an asymmetry outside the uncertainties of the evaluation process of the measurement data. The perpendicular velocity is investigated between mid-radius and the plasma edge and follows the poloidal dependence of the E × B drift velocity regardless of the probed turbulence structure size. Compared to measurements of a charge exchange recombination spectroscopy diagnostic this points towards a significantly smaller phase velocity than the E × B drift velocity. The analysis technique is presented in a representative discharge together with a sensitivity study of the impact of density, magneto hydrodynamic equilibrium and diagnostic alignment on the interpretation of the measured Doppler shift using ray tracing and thus on poloidal asymmetries. Three more highly different plasma scenarios with poloidally symmetric velocity profiles are shown. (10.1088/1361-6587/abd896)
DOI : 10.1088/1361-6587/abd896
Two‐dimensional velocity of the magnetic structure observed on 11 July 2017 by the Magnetospheric Multiscale spacecraft
- Denton Richard
- Torbert Roy
- Hasegawa Hiroshi
- Genestreti Kevin
- Manuzzo Roberto
- Belmont Gérard
- Rezeau Laurence
- Califano Francesco
- Nakamura Rumi
- Egedal Jan
- Le Contel Olivier
- Burch James
- Gershman Daniel
- Dors Ivan
- Argall Matthew
- Russell Christopher
- Strangeway Robert
- Giles Barbara
Journal of Geophysical Research Space Physics, American Geophysical Union/Wiley, 2021, 126. In order to determine particle velocities and electric field in the frame of the magnetic structure, one first needs to determine the velocity of the magnetic structure in the frame of the spacecraft observations. Here, we demonstrate two methods to determine a two-dimensional magnetic structure velocity for the magnetic reconnection event observed in the magnetotail by the Magnetospheric Multiscale (MMS) spacecraft on July 11, 2017, Spatio-Temporal Difference (STD) and the recently developed polynomial reconstruction method. Both of these methods use the magnetic field measurements; the reconstruction technique also uses the current density measured by the particle instrument. We find rough agreement between the results of our methods and with other velocity determinations previously published. We also explain a number of features of STD and show that the polynomial reconstruction technique is most likely to be valid within a distance of 2 spacecraft spacings from the centroid of the MMS spacecraft. Both of these methods are susceptible to contamination by magnetometer calibration errors. (10.1029/2020JA028705)
DOI : 10.1029/2020JA028705
Comparative Analysis of the Various Generalized Ohm's Law Terms in Magnetosheath Turbulence as Observed by Magnetospheric Multiscale
- Stawarz J.
- Matteini L.
- Parashar T.
- Franci L.
- Eastwood J.
- Gonzalez C. A
- Gingell I. L
- Burch J.
- Ergun R.
- Ahmadi N.
- Giles B. L
- Gershman D. J
- Le Contel O.
- Lindqvist P.-A ‐a
- Russell C. T
- Strangeway R. J
- Torbert R. B
Journal of Geophysical Research Space Physics, American Geophysical Union/Wiley, 2021, 126 (1). Decomposing the electric field (E) into the contributions from generalized Ohm's law provides key insight into both nonlinear and dissipative dynamics across the full range of scales within a plasma. Using high-resolution, multispacecraft measurements of three intervals in Earth's magnetosheath from the Magnetospheric Multiscale mission, the influence of the magnetohydrodynamic, Hall, electron pressure, and electron inertia terms from Ohm's law, as well as the impact of a finite electron mass, on the turbulent E spectrum are examined observationally for the first time. The magnetohydrodynamic, Hall, and electron pressure terms are the dominant contributions to E over the accessible length scales, which extend to scales smaller than the electron gyroradius at the greatest extent, with the Hall and electron pressure terms dominating at sub-ion scales. The strength of the nonideal electron pressure contribution is stronger than expected from linear kinetic Alfvén waves and a partial antialignment with the Hall electric field is present, linked to the relative importance of electron diamagnetic currents in the turbulence. The relative contribution of linear and nonlinear electric fields scale with the turbulent fluctuation amplitude, with nonlinear contributions playing the dominant role in shaping E for the intervals examined in this study. Overall, the sum of the Ohm's law terms and measured E agree to within ∼20% across the observable scales. These results both confirm general expectations about the behavior of E in turbulent plasmas and highlight features that should be explored further theoretically. Plain Language Summary Complex turbulent motions are observed in plasmas throughout the Universe and act to transfer energy from large-scale fluctuations to small-scale fluctuations, which can be more easily dissipated into the thermal energy of the particles. Electric fields in these plasmas play a central role in enabling the exchange of energy between the magnetic field and the motion of the charged particles and are, therefore, important for disentangling the complex nonlinear dynamics and dissipative processes. Using cutting-edge, high-resolution, multispacecraft measurements from NASA's Magnetospheric Multiscale mission, we decompose the electric field in Earth's turbulent magnetosheath into the various terms from generalized Ohm's law, which governs the behavior of the electric field across the wide range of length scales in the plasma. The results confirm a number of general expectations about the relative behavior of the terms in Ohm's law, as well as highlight several new features that are significant for understanding the nonlinear behavior and turbulent dissipation at different scales within the plasma. (10.1029/2020ja028447)
DOI : 10.1029/2020ja028447

Retour aux années