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52. Plasma-neutral gas interactions in various space environments

Author

De Keyser, Johan, Yau, Andrew, Liu, Yong, Tian, Feng, Rong, Zhaojin, Kallio, Esa, Ulich, Thomas, Dandouras, Iannis, Henri, Pierre, Saur, Joachim, Daglis, Ioannis, Oyama, Shin-ichiro, Abe, Takumi, Sakanoi, Takeshi, Tsuda, Takuo, Taguchi, Satoshi, Mann, Ingrid, Marghitu, Octav, Yamauchi, Masatoshi, Shimoyama, Manabu, Ivchenko, Nickolay, Wurz, Peter, Beth, Arnaud, Nicolaou, Georgios, Dunlop, Malcolm, Parks, George, Kucharek, Harald, Tsurutani, Bruce, Turner, Drew, Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Finnish Meteorological Institute (FMI), Sodankylä Geophysical Observatory, University of Oulu, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institute for Geophysics and Meteorology [Köln] (IGM), University of Cologne, Swedish Institute of Space Physics [Kiruna] (IRF), Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE), Space Science and Technology Department [Didcot] (RAL Space), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC), Space Sciences Laboratory [Berkeley] (SSL), University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Universität Bern [Bern], University of California [Berkeley], University of California-University of California, and California Institute of Technology (CALTECH)-NASA

Subjects
[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph]
Published
2019

54. Atmospheric loss from the dayside open polar region and its dependence on geomagnetic activity: implications for atmospheric escape on evolutionary timescales

Author

Slapak, Rikard, Schillings, Audrey, Nilsson, Hans, Yamauchi, Masatoshi, Westerberg, Lars-Göran, Dandouras, Iannis, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU]Sciences of the Universe [physics], TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY
Abstract

International audience; We have investigated the total O+ escape rate from the dayside open polar region and its dependence on geomagnetic activity, specifically Kp. Two different escape routes of magnetospheric plasma into the solar wind, the plasma mantle, and the high-latitude dayside magnetosheath have been investigated separately. The flux of O+ in the plasma mantle is sufficiently fast to subsequently escape further down the magnetotail passing the neutral point, and it is nearly 3 times larger than that in the dayside magnetosheath. The contribution from the plasma mantle route is estimated as ∼ 3. 9 × 1024exp(0. 45 Kp) [s-1] with a 1 to 2 order of magnitude range for a given geomagnetic activity condition. The extrapolation of this result, including escape via the dayside magnetosheath, indicates an average O+ escape of 3 × 1026 s-1 for the most extreme geomagnetic storms. Assuming that the range is mainly caused by the solar EUV level, which was also larger in the past, the average O+ escape could have reached 1027-28 s-1 a few billion years ago. Integration over time suggests a total oxygen escape from ancient times until the present roughly equal to the atmospheric oxygen content today.

Published
2018
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55. Relative outflow enhancements during major geomagnetic storms – Cluster observations

Author

Schillings, Audrey, Nilsson, Hans, Slapak, Rikard, Yamauchi, Masatoshi, and Westerberg, Lars-Göran

Abstract

The rate of ion outflow from the polar ionosphere is known to vary by orders of magnitude, depending on the geomagnetic activity. However, the upper limit of the outflow rate during the largest geomagnetic storms is not well constrained due to poor spatial coverage during storm events. In this paper, we analyse six major geomagnetic storms between 2001 and 2004 using Cluster data. The six major storms fulfil the criteria of Dst 7+. Since the shape of the magnetospheric regions (plasma mantle, lobe and inner magnetosphere) are distorted during large magnetic storms, we use both plasma beta (β) and ion characteristics to define a spatial box where the upward O+ flux scaled to an ionospheric reference altitude for the extreme event is observed. The relative enhancement of the scaled outflow in the spatial boxes as compared to the data from the full year when the storm occurred is estimated. Only O+ data were used because H+ may have a solar wind origin. The storm time data for most cases showed up as a clearly distinguishable separate peak in the distribution toward the largest fluxes observed. The relative enhancement in the outflow region during storm time is 1 to 2 orders of magnitude higher compared to less disturbed time. The largest relative scaled outflow enhancement is 83 (7 November 2004) and the highest scaled O+ outflow observed is 2 × 1014 m−2 s−1 (29 October 2003).

Published
2018

56. Corrigendum to 'Atmospheric loss from the dayside open polar region and its dependence on geomagnetic activity: implications for atmospheric escape on evolutionary timescales' published in Ann. Geophys., 35, 721–731, 2017

Author

Slapak, Rikard, Schillings, Audrey, Nilsson, Hans, Yamauchi, Masatoshi, and Westerberg, Lars-Göran

Subjects
Rymd- och flygteknik, Fluid Mechanics and Acoustics, Aerospace Engineering, Strömningsmekanik och akustik
Abstract

Erratum in: Annales Geophysicae, vol. 35, iss. 3, p. 721–731, DOI: 10.5194/angeo-35-721-2017

Published
2018

65. Quantification of the total ion transport in the near-Earth plasma sheet

Author

Slapak, Rikard, Hamrin, Maria, Pitkänen, Timo, Yamauchi, Masatoshi, Nilsson, Hans, Karlsson, Tomas, and Schillings, Audrey

Subjects
Fusion, plasma och rymdfysik, plasma sheet), TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Astrophysics::High Energy Astrophysical Phenomena, Physics::Space Physics, Fusion, Plasma and Space Physics, Magnetospheric physics (magnetospheric configuration and dynamics
Abstract

Recent studies strongly suggest that a majority of the observed O+ cusp outflows will eventually escape into the solar wind, rather than be transported to the plasma sheet. Therefore, an investigation of plasma sheet flows will add to these studies and give a more complete picture of magnetospheric ion dynamics. Specifically, it will provide a greater understanding of atmospheric loss. We have used Cluster spacecraft 4 to quantify the H+ and O+ total transports in the near-Earth plasma sheet, using data covering 2001–2005. The results show that both H+ and O+ have earthward net fluxes of the orders of 1026 and 1024 s−1, respectively. The O+ plasma sheet return flux is 1 order of magnitude smaller than the O+ outflows observed in the cusps, strengthening the view that most ionospheric O+ outflows do escape. The H+ return flux is approximately the same as the ionospheric outflow, suggesting a stable budget of H+ in the magnetosphere. However, low-energy H+, not detectable by the ion spectrometer, is not considered in our study, leaving the complete magnetospheric H+ circulation an open question. Studying tailward flows separately reveals a total tailward O+ flux of about 0. 5 × 1025 s−1, which can be considered as a lower limit of the nightside auroral region O+ outflow. Lower velocity flows ( −1) contribute most to the total transports, whereas the high-velocity flows contribute very little, suggesting that bursty bulk flows are not dominant in plasma sheet mass transport.

Published
2017

69. Preface

Author

Halekas, Jasper, Modolo, Ronan, Watanabe, Shigeto, and Yamauchi, Masatoshi

Published
2012
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70. Atmospheric loss from the dayside open polar region and its dependence on geomagnetic activity: implications for atmospheric escape on evolutionary timescales

Author

Slapak, Rikard, Schillings, Audrey, Nilsson, Hans, Yamauchi, Masatoshi, Westerberg, Lars-Göran, Dandouras, Iannis, Slapak, Rikard, Schillings, Audrey, Nilsson, Hans, Yamauchi, Masatoshi, Westerberg, Lars-Göran, and Dandouras, Iannis

Abstract

We have investigated the total O+ escape rate from the dayside open polar region and its dependence on geomagnetic activity, specifically Kp. Two different escape routes of magnetospheric plasma into the solar wind, the plasma mantle, and the high-latitude dayside magnetosheath have been investigated separately. The flux of O+ in the plasma mantle is sufficiently fast to subsequently escape further down the magnetotail passing the neutral point, and it is nearly 3 times larger than that in the dayside magnetosheath. The contribution from the plasma mantle route is estimated as ∼ 3. 9 × 1024exp(0. 45 Kp) [s−1] with a 1 to 2 order of magnitude range for a given geomagnetic activity condition. The extrapolation of this result, including escape via the dayside magnetosheath, indicates an average O+ escape of 3 × 1026 s−1 for the most extreme geomagnetic storms. Assuming that the range is mainly caused by the solar EUV level, which was also larger in the past, the average O+ escape could have reached 1027–28 s−1 a few billion years ago. Integration over time suggests a total oxygen escape from ancient times until the present roughly equal to the atmospheric oxygen content today., Validerad;2017;Nivå 2;2017-06-30 (andbra);License fulltext: CC BY;Please read the corrigendum first before accessing the article.

Published
2017
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71. Evolution of the ion environment of comet 67P during the Rosetta mission as seen by RPC-ICA

Author

Nilsson, Hans, Wieser, Gabriella Stenberg, Behar, Etienne, Gunell, Herbert, Wieser, Martin, Galand, Marina, Wedlund, Cyril Simon, Alho, Markku, Goetz, Charlotte, Yamauchi, Masatoshi, Henri, Pierre, Odelstad, Elias, Vigren, Erik, Nilsson, Hans, Wieser, Gabriella Stenberg, Behar, Etienne, Gunell, Herbert, Wieser, Martin, Galand, Marina, Wedlund, Cyril Simon, Alho, Markku, Goetz, Charlotte, Yamauchi, Masatoshi, Henri, Pierre, Odelstad, Elias, and Vigren, Erik

Abstract

Rosetta has followed comet 67P from low activity at more than 3.6 au heliocentric distance to high activity at perihelion (1.24 au) and then out again. We provide a general overview of the evolution of the dynamic ion environment using data from the RPC-ICA ion spectrometer. We discuss where Rosetta was located within the evolving comet magnetosphere. For the initial observations, the solar wind permeated all of the coma. In 2015 mid-April, the solar wind started to disappear from the observation region, to re-appear again in 2015 December. Low-energy cometary ions were seen at first when Rosetta was about 100 km from the nucleus at 3.6 au, and soon after consistently throughout the mission except during the excursions to farther distances from the comet. The observed flux of low-energy ions was relatively constant due to Rosetta's orbit changing with comet activity. Accelerated cometary ions, moving mainly in the antisunward direction gradually became more common as comet activity increased. These accelerated cometary ions kept being observed also after the solar wind disappeared from the location of Rosetta, with somewhat higher fluxes further away from the nucleus. Around perihelion, when Rosetta was relatively deep within the comet magnetosphere, the fluxes of accelerated cometary ions decreased, as did their maximum energy. The disappearance of more energetic cometary ions at close distance during high activity is suggested to be due to a flow pattern where these ions flow around the obstacle of the denser coma or due to charge exchange losses.

Published
2017
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72. Mars Under Primordial Solar Wind Conditions: Mars Express Observations of the Strongest CME Detected at Mars Under Solar Cycle #24 and its Impact on Atmospheric Ion Escape

Author

Ramstad, Robin, Barabash, Stas, Futaana, Yoshifumi, Yamauchi, Masatoshi, Nilsson, Hans, Holmström, Mats, Ramstad, Robin, Barabash, Stas, Futaana, Yoshifumi, Yamauchi, Masatoshi, Nilsson, Hans, and Holmström, Mats

Abstract

An extremely strong Coronal Mass Ejection (CME) impacted Mars on 12 July 2011, while theMars Express spacecraft was present inside the nightside ionosphere. Estimated solar wind density andspeed during the event are 39 particles cm−3 and 730 km/s, corresponding to nominal solar wind fluxat Mars when the solar system was ∼1.1 Ga old. Comparing with expected average atmospheric heavy ionfluxes under similar XUV conditions, the CME impact is found to have no significant effect on the escaperate 3.3 × 1024 s−1, with an upper limit at 1025 s−1 if the observed tail contraction is not taken into account.On the subsequent orbit, 7 h later after magnetosphere response, fluxes were only 2.4% of average. As such,even under primordial solar wind conditions we are unable to find support for a strong solar wind-driven ion escape, rather the main effect appears to be acceleration of the escaping ions by ×10–×20 typicalcharacteristic energy.

Published
2017
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77. Erratum: Evolution of the ion environment of comet 67P during the Rosetta mission as seen by RPC-ICA

Author

Nilsson, Hans, primary, Wieser, Gabriella Stenberg, additional, Behar, Etienne, additional, Gunell, Herbert, additional, Wieser, Martin, additional, Galand, Marina, additional, Simon Wedlund, Cyril, additional, Alho, Markku, additional, Goetz, Charlotte, additional, Yamauchi, Masatoshi, additional, Henri, Pierre, additional, Odelstad, Elias, additional, and Vigren, Erik, additional

Published
2017
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78. Evolution of the ion environment of comet 67P during the Rosetta mission as seen by RPC-ICA

Author

Nilsson, Hans, primary, Wieser, Gabriella Stenberg, additional, Behar, Etienne, additional, Gunell, Herbert, additional, Wieser, Martin, additional, Galand, Marina, additional, Simon Wedlund, Cyril, additional, Alho, Markku, additional, Goetz, Charlotte, additional, Yamauchi, Masatoshi, additional, Henri, Pierre, additional, Odelstad, Elias, additional, and Vigren, Erik, additional

Published
2017
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80. Birth of a comet magnetosphere : A spring of water ions

Author

Nilsson, Hans, Wieser, Gabriella Stenberg, Behar, Etienne, Wedlund, Cyril Simon, Gunell, Herbert, Yamauchi, Masatoshi, Lundin, Rickard, Barabash, Stas, Wieser, Martin, Carr, Chris, Cupido, Emanuele, Burch, James L., Fedorov, Andrei, Sauvaud, Jean-Andre, Koskinen, Hannu, Kallio, Esa, Lebreton, Jean-Pierre, Eriksson, Anders, Edberg, Niklas, Goldstein, Raymond, Henri, Pierre, Koenders, Christoph, Mokashi, Prachet, Nemeth, Zoltan, Richter, Ingo, Szego, Karoly, Volwerk, Martin, Vallat, Claire, Rubin, Martin, Nilsson, Hans, Wieser, Gabriella Stenberg, Behar, Etienne, Wedlund, Cyril Simon, Gunell, Herbert, Yamauchi, Masatoshi, Lundin, Rickard, Barabash, Stas, Wieser, Martin, Carr, Chris, Cupido, Emanuele, Burch, James L., Fedorov, Andrei, Sauvaud, Jean-Andre, Koskinen, Hannu, Kallio, Esa, Lebreton, Jean-Pierre, Eriksson, Anders, Edberg, Niklas, Goldstein, Raymond, Henri, Pierre, Koenders, Christoph, Mokashi, Prachet, Nemeth, Zoltan, Richter, Ingo, Szego, Karoly, Volwerk, Martin, Vallat, Claire, and Rubin, Martin

Abstract

The Rosetta mission shall accompany comet 67P/Churyumov-Gerasimenko from a heliocentric distance of >3.6 astronomical units through perihelion passage at 1.25 astronomical units, spanning low and maximum activity levels. Initially, the solar wind permeates the thin comet atmosphere formed from sublimation, until the size and plasma pressure of the ionized atmosphere define its boundaries: A magnetosphere is born. Using the Rosetta Plasma Consortium ion composition analyzer, we trace the evolution from the first detection of water ions to when the atmosphere begins repelling the solar wind (similar to 3.3 astronomical units), and we report the spatial structure of this early interaction. The near-comet water population comprises accelerated ions (<800 electron volts), produced upstream of Rosetta, and lower energy locally produced ions; we estimate the fluxes of both ion species and energetic neutral atoms.

Published
2015
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81. O+ Escape During the Extreme Space Weather Event of 4–10 September 2017.

Author

Schillings, Audrey, Nilsson, Hans, Slapak, Rikard, Wintoft, Peter, Yamauchi, Masatoshi, Wik, Magnus, Dandouras, Iannis, and Carr, Chris M.

Subjects
SPACE environment, IONOSPHERE, SOLAR flares, MAGNETIC storms, CORONAL mass ejections
Abstract

We have investigated the consequences of extreme space weather on ion outflow from the polar ionosphere by analyzing the solar storm that occurred early September 2017, causing a severe geomagnetic storm. Several X‐flares and coronal mass ejections were observed between 4 and 10 September. The first shock—likely associated with a coronal mass ejection—hit the Earth late on 6 September, produced a storm sudden commencement, and began the initial phase of the storm. It was followed by a second shock, approximately 24 hr later, that initiated the main phase and simultaneously the Dst index dropped to Dst = −142 nT and Kp index reached Kp = 8. Using COmposition DIstribution Function data on board Cluster satellite 4, we estimated the ionospheric O+ outflow before and after the second shock. We found an enhancement in the polar cap by a factor of 3 for an unusually high ionospheric O+ outflow (mapped to an ionospheric reference altitude) of 1013 m−2 s−1. We suggest that this high ionospheric O+ outflow is due to a preheating of the ionosphere by the multiple X‐flares. Finally, we briefly discuss the space weather consequences on the magnetosphere as a whole and the enhanced O+ outflow in connection with enhanced satellite drag. Key Points: Multiple X‐flares and three CMEs occurred in 4‐10 September 2017, CMEs are the driver of the storm, whereas the X‐flares might have preheated the ionosphereThe O+ outflow in the polar cap and cusp is estimated to be 1013 m‐2s‐1 during the main phase of the geomagnetic stormThe entire magnetosphere is affected by space weather event, and the O+ enhancement in the cusp might be a good indicator for satellite drag fluctuations [ABSTRACT FROM AUTHOR]

Published
2018
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82. Equatorially confined warm trapped ions at around 100 eV near the plasmapause

Author

Yamauchi, Masatoshi, Dandouras, Iannis, Rème, Henri, El-Lemdani Mazouz, Farida, Swedish Institute of Space Physics [Kiruna] (IRF), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), HELIOS - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Swedish National Space Board, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Wave-particle interaction, Inner magnetosphere, Ring distribution, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], Warm Ion, Plasmapause
Abstract

International audience; Near the equatorial plasmapause at around 4-5 Earth radius (RE) geocentric distance, pancake distributed tens of eV ions are sometimes found, as previously reported by Olsen et al. (1987). Cluster CIS data during perigee traversals in 2001-2002 (nearly 200 traversals) revealed new features of these equatorially-trapped warm ions. (1) The characteristic energy of He+ is often higher than that of H+. (2) Some events show non-thermal ring distribution for He+ rather than superthermal pancake distribution. H+ can also have the ring distribution in such events. (3) While majority of the events are dispersion-free, some events show energy-time dispersion, indicating drifts from different local times. (4) The time scale of the development is about an hour, which is much shorter than the drifting time of these ions around the Earth. Cluster statistics also confirmed some results from the previous studies: (5) These ions are confined within a few degrees of latitudinal range near the equator, and have nearly 90{degree sign} pitch angles. (6) At a geocentric distance of about 4-4.5 RE where Cluster traversed the equator during its perigee, the probability of observing clear events is about 40-45% in the noon and dusk sectors and about 20-25% in the night-to-dawn sector. (7) They are dominated by H+ with variable content of He+. The He+/H+ ratio is much less than 5% for the majority of the cases.

Published
2012
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83. Birth of a comet magnetosphere: A spring of water ions

Author

Nilsson, Hans, primary, Stenberg Wieser, Gabriella, additional, Behar, Etienne, additional, Wedlund, Cyril Simon, additional, Gunell, Herbert, additional, Yamauchi, Masatoshi, additional, Lundin, Rickard, additional, Barabash, Stas, additional, Wieser, Martin, additional, Carr, Chris, additional, Cupido, Emanuele, additional, Burch, James L., additional, Fedorov, Andrei, additional, Sauvaud, Jean-André, additional, Koskinen, Hannu, additional, Kallio, Esa, additional, Lebreton, Jean-Pierre, additional, Eriksson, Anders, additional, Edberg, Niklas, additional, Goldstein, Raymond, additional, Henri, Pierre, additional, Koenders, Christoph, additional, Mokashi, Prachet, additional, Nemeth, Zoltan, additional, Richter, Ingo, additional, Szego, Karoly, additional, Volwerk, Martin, additional, Vallat, Claire, additional, and Rubin, Martin, additional

Published
2015
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84. Towards low-cost Swedish planetary missions

Author

Barabash, Stas, Norberg, Olle, Wahlund, Jan-Erik, Yamauchi, Masatoshi, Grahn, Sven, Persson, Staffan, and Blomberg, Lars

Subjects
Fusion, plasma och rymdfysik, Fusion, Plasma and Space Physics
Abstract

As a continuation of the Swedish tradition of designing small and high-quality spacecrafts such as Freja, Astrid, Munin, and SMART-1, Swedish scientists and engineers have proposed aggressive but feasible missions as the next national-level target: (1) an interplanetary plasma module (or subsatellite) Saga, and (2) a technology mission Prisma. The Saga micro-satellite contains a separation mechanism, technologically-challenging communication package, and plasma payload with an estimated total mass of 37kg to make the mission possible with a piggy-back launch or by attaching to another planetary mission. The Prisma mission consists of a semi-coordinated dual micro- and nano-satellites flying together in Earth orbit with state-of-art instruments to test. Both projects aim to develop and test new key spacecraft technologies. Qc 20120321

Published
2004

85. Outflowing protons and heavy ions as a source for the sub-keV ringcurrent

Author

Giang, Tony, Hamrin, Maria, Yamauchi, Masatoshi, Lundin, Rickard, Nilsson, Hans, Ebihara, Yusuke, Rème, Henri, Dandouras, Iannis, Vallat, C., Bavassano-Cattaneo, M. B., Klecker, B., Korth, A., Kistler, L. M., McCarthy, M., Giang, Tony, Hamrin, Maria, Yamauchi, Masatoshi, Lundin, Rickard, Nilsson, Hans, Ebihara, Yusuke, Rème, Henri, Dandouras, Iannis, Vallat, C., Bavassano-Cattaneo, M. B., Klecker, B., Korth, A., Kistler, L. M., and McCarthy, M.

Abstract

Data from the Cluster CIS instrument have been used for studying proton and heavy ion (O+ and He+ ) char- acteristics of the sub-keV ring current. Thirteen events with dispersed heavy ions (O+ and He+ ) were identified out of two years (2001 and 2002) of Cluster data. Allevents took place during rather geomagnetically quiet periods. Three of those events have been investigated in detail: 21 August 2001, 26 November 2001 and 20 February 2002. These events were chosen from varying magnetic local times (MLT), and they showed different characteristics. In this article, we discuss the potential source for sub-keV ring current ions. We show that: (1) outflows of terrestrialsub-keV ions are supplied to the ring current also during quiet geomagnetic conditions; (2) the composition of the out-flow implies an origin that covers an altitude interval from the low-altitude ionosphere to the plasmasphere, and (3) terrestrial ions are moving upward along magnetic field lines, at times forming narrow collimated beams, but frequently also as broad beams. Over time, the ion beams are expected to gradually become isotropised as a result of wave-particleinteraction, eventually taking the form of isotropic drifting sub-keV ion signatures. We argue that the sub-keV energy-time dispersed signatures originate from field-aligned terrestrial ion energising and outflow, which may occur at all local times and persist also during quiet times.

Published
2009
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90. Cusp and boundary layer observations by INTERBALL

Author

Sandahl, Ingrid, primary, Lundin, Rickard, additional, Yamauchi, Masatoshi, additional, Eklund, Ulrik, additional, Safrankova, Jana, additional, Nemecek, Zdenek, additional, Kudela, Karel, additional, Lepping, Ronald P., additional, Lin, Robert P., additional, Lutsenko, Volt N., additional, and Sauvaud, Jean-André, additional

Published
1997
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