Articles | Volume 35, issue 4
https://doi.org/10.5194/angeo-35-869-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/angeo-35-869-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Quantification of the total ion transport in the near-Earth plasma sheet
Division of Space Technology, Luleå University of Technology, Kiruna, Sweden
Maria Hamrin
Department of Physics, Umeå University, Umeå, Sweden
Timo Pitkänen
Department of Physics, Umeå University, Umeå, Sweden
Masatoshi Yamauchi
Swedish Institute of Space Physics, Kiruna, Sweden
Hans Nilsson
Division of Space Technology, Luleå University of Technology, Kiruna, Sweden
Swedish Institute of Space Physics, Kiruna, Sweden
Tomas Karlsson
Space and Plasma Physics, School of Electrical Engineering, Royal Institute of Technology, Stockholm, Sweden
Audrey Schillings
Division of Space Technology, Luleå University of Technology, Kiruna, Sweden
Swedish Institute of Space Physics, Kiruna, Sweden
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Audrey Schillings, Herbert Gunell, Hans Nilsson, Alexandre De Spiegeleer, Yusuke Ebihara, Lars G. Westerberg, Masatoshi Yamauchi, and Rikard Slapak
Ann. Geophys., 38, 645–656, https://doi.org/10.5194/angeo-38-645-2020, https://doi.org/10.5194/angeo-38-645-2020, 2020
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The Earth's atmosphere is constantly losing molecules and charged particles, amongst them oxygen ions or O+. Quantifying this loss provides information about the evolution of the atmosphere on geological timescales. In this study, we investigate the final destination of O+ observed with Cluster satellites in a high-altitude magnetospheric region (plasma mantle) by tracing the particles forward in time using simulations. We find that approximately 98 % of O+ escapes the Earth's magnetosphere.
Patrik Krcelic, Stein Haaland, Lukas Maes, Rikard Slapak, and Audrey Schillings
Ann. Geophys., 38, 491–505, https://doi.org/10.5194/angeo-38-491-2020, https://doi.org/10.5194/angeo-38-491-2020, 2020
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In this paper we have used Cluster EDI data in combination with the CODIF cusp dataset from Slapak et al. (2017) to obtain parallel and convection velocities for oxygen ions; 69 % of total oxygen outflow from the high-altitude cusps escapes the magnetosphere on average; 50 % escapes tailward beyond the distant X-line. The oxygen capture-versus-escape ratio is highly dependent on geomagnetic conditions. During active conditions, the majority of oxygen outflow is convected to the plasma sheet.
Masatoshi Yamauchi and Rikard Slapak
Ann. Geophys., 36, 1–12, https://doi.org/10.5194/angeo-36-1-2018, https://doi.org/10.5194/angeo-36-1-2018, 2018
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Extraction of the solar wind kinetic energy (∆K) by mass loading of escaping O+ is modelled in the exterior cusp and plasma mantle of the Earth. We found ∆K proportional to mass flux of escaping ions and square of solar wind velocity, but independent to the other parameters. The amount is sufficient to power the cusp field-aligned currents, further enhancing ion escape through Joule heating of the ionospheric ions, completing positive feedback to enhance escape with geomagnetic activities.
Audrey Schillings, Hans Nilsson, Rikard Slapak, Masatoshi Yamauchi, and Lars-Göran Westerberg
Ann. Geophys., 35, 1341–1352, https://doi.org/10.5194/angeo-35-1341-2017, https://doi.org/10.5194/angeo-35-1341-2017, 2017
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The Earth's atmosphere is constantly losing ions and in particular oxygen ions. This phenomenon is important to understand the atmospheric evolution on a large timescale. In this study, the O+ outflow is estimated during six extreme geomagnetic storms using the European Cluster mission data. These estimations are compared with average magnetospheric conditions and show that during those six extreme storms, the O+ outflow is approximately 2 orders of magnitude higher.
Rikard Slapak, Audrey Schillings, Hans Nilsson, Masatoshi Yamauchi, Lars-Göran Westerberg, and Iannis Dandouras
Ann. Geophys., 35, 721–731, https://doi.org/10.5194/angeo-35-721-2017, https://doi.org/10.5194/angeo-35-721-2017, 2017
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In this study, we have used Cluster satellite data to quantify the ionospheric oxygen ion (O+) escape into the solar wind and its dependence on geomagnetic activity. During times of high activity, the escape may be 2 orders of magnitude higher than under quiet conditions, strongly suggesting that the escape rate was much higher when the Sun was young. The results are important for future studies regarding atmospheric loss over geological timescales.
R. Slapak, H. Nilsson, L. G. Westerberg, and R. Larsson
Ann. Geophys., 33, 301–307, https://doi.org/10.5194/angeo-33-301-2015, https://doi.org/10.5194/angeo-33-301-2015, 2015
Sota Nanjo, Masatoshi Yamauchi, Magnar Gullikstad Johnsen, Yoshihiro Yokoyama, Urban Brändström, Yasunobu Ogawa, Anna Naemi Willer, and Keisuke Hosokawa
EGUsphere, https://doi.org/10.5194/egusphere-2024-3277, https://doi.org/10.5194/egusphere-2024-3277, 2024
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Our research explored the "shock aurora," caused by the impact of solar wind particles on Earth's magnetic field. On February 26, 2023, we observed this rare event on the nightside, where such observations are difficult. Ground-based cameras revealed new structural features, including undulating and jumping patterns. These results provide fresh insights into the complex interactions between the solar wind and Earth's magnetosphere, enhancing our understanding of space weather effects.
Adrian Pöppelwerth, Georg Glebe, Johannes Z. D. Mieth, Florian Koller, Tomas Karlsson, Zoltán Vörös, and Ferdinand Plaschke
Ann. Geophys., 42, 271–284, https://doi.org/10.5194/angeo-42-271-2024, https://doi.org/10.5194/angeo-42-271-2024, 2024
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In the magnetosheath, a near-Earth region of space, we observe increases in plasma velocity and density, so-called jets. As they propagate towards Earth, jets interact with the ambient plasma. We study this interaction with three spacecraft simultaneously to infer their sizes. While previous studies have investigated their size almost exclusively statistically, we demonstrate a new method of determining the sizes of individual jets.
Tomas Karlsson, Ferdinand Plaschke, Austin N. Glass, and Jim M. Raines
Ann. Geophys., 42, 117–130, https://doi.org/10.5194/angeo-42-117-2024, https://doi.org/10.5194/angeo-42-117-2024, 2024
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The solar wind interacts with the planets in the solar system and creates a supersonic shock in front of them. The upstream region of this shock contains many complicated phenomena. One such phenomenon is small-scale structures of strong magnetic fields (SLAMS). These SLAMS have been observed at Earth and are important in determining the properties of space around the planet. Until now, SLAMS have not been observed at Mercury, but we show for the first time that SLAMS also exist there.
Henriette Trollvik, Tomas Karlsson, and Savvas Raptis
Ann. Geophys., 41, 327–337, https://doi.org/10.5194/angeo-41-327-2023, https://doi.org/10.5194/angeo-41-327-2023, 2023
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The solar wind is in a plasma state and can exhibit a range of phenomena like waves and instabilities. One observed phenomenon in the solar wind is magnetic holes (MHs). They are localized depressions in the magnetic field. We studied the motion of MHs using the multispacecraft ESA Cluster mission. We derived their velocities in the solar wind frame and found that both linear and rotational MHs are convected with the solar wind.
Masatoshi Yamauchi and Urban Brändström
Geosci. Instrum. Method. Data Syst., 12, 71–90, https://doi.org/10.5194/gi-12-71-2023, https://doi.org/10.5194/gi-12-71-2023, 2023
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Potential users of all-sky aurora images even include power companies, tourists, and aurora enthusiasts. However, these potential users are normally not familiar with interpreting these images. To make them comprehensive for more users, we developed an automatic evaluation system of auroral activity level. The method involves two steps: first making a simple set of numbers that describes the auroral activity and then further simplifying them into several levels (Level 6 is an auroral explosion).
Tomas Karlsson, Henriette Trollvik, Savvas Raptis, Hans Nilsson, and Hadi Madanian
Ann. Geophys., 40, 687–699, https://doi.org/10.5194/angeo-40-687-2022, https://doi.org/10.5194/angeo-40-687-2022, 2022
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Magnetic holes are curious localized dropouts of magnetic field strength in the solar wind (the flow of ionized gas continuously streaming out from the sun). In this paper we show that these magnetic holes can cross the bow shock (where the solar wind brake down to subsonic velocity) and enter the region close to Earth’s magnetosphere. These structures may therefore represent a new type of non-uniform solar wind–magnetosphere interaction.
Charlotte Goetz, Herbert Gunell, Fredrik Johansson, Kristie LLera, Hans Nilsson, Karl-Heinz Glassmeier, and Matthew G. G. T. Taylor
Ann. Geophys., 39, 379–396, https://doi.org/10.5194/angeo-39-379-2021, https://doi.org/10.5194/angeo-39-379-2021, 2021
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Boundaries in the plasma around comet 67P separate regions with different properties. Many have been identified, including a new boundary called an infant bow shock. Here, we investigate how the plasma and fields behave at this boundary and where it can be found. The main result is that the infant bow shock occurs at intermediate activity and intermediate distances to the comet. Most plasma parameters behave as expected; however, some inconsistencies indicate that the boundary is non-stationary.
Minna Palmroth, Savvas Raptis, Jonas Suni, Tomas Karlsson, Lucile Turc, Andreas Johlander, Urs Ganse, Yann Pfau-Kempf, Xochitl Blanco-Cano, Mojtaba Akhavan-Tafti, Markus Battarbee, Maxime Dubart, Maxime Grandin, Vertti Tarvus, and Adnane Osmane
Ann. Geophys., 39, 289–308, https://doi.org/10.5194/angeo-39-289-2021, https://doi.org/10.5194/angeo-39-289-2021, 2021
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Magnetosheath jets are high-velocity features within the Earth's turbulent magnetosheath, separating the Earth's magnetic domain from the solar wind. The characteristics of the jets are difficult to assess statistically as a function of their lifetime because normally spacecraft observe them only at one position within the magnetosheath. This study first confirms the accuracy of the model used, Vlasiator, by comparing it to MMS spacecraft, and then carries out the first jet lifetime statistics.
Martin Volwerk, David Mautner, Cyril Simon Wedlund, Charlotte Goetz, Ferdinand Plaschke, Tomas Karlsson, Daniel Schmid, Diana Rojas-Castillo, Owen W. Roberts, and Ali Varsani
Ann. Geophys., 39, 239–253, https://doi.org/10.5194/angeo-39-239-2021, https://doi.org/10.5194/angeo-39-239-2021, 2021
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The magnetic field in the solar wind is not constant but varies in direction and strength. One of these variations shows a strong local reduction of the magnetic field strength and is called a magnetic hole. These holes are usually an indication that there is, or has been, a temperature difference in the plasma of the solar wind, with the temperature along the magnetic field lower than perpendicular. The MMS spacecraft data have been used to study the characteristics of these holes near Earth.
Minna Palmroth, Maxime Grandin, Theodoros Sarris, Eelco Doornbos, Stelios Tourgaidis, Anita Aikio, Stephan Buchert, Mark A. Clilverd, Iannis Dandouras, Roderick Heelis, Alex Hoffmann, Nickolay Ivchenko, Guram Kervalishvili, David J. Knudsen, Anna Kotova, Han-Li Liu, David M. Malaspina, Günther March, Aurélie Marchaudon, Octav Marghitu, Tomoko Matsuo, Wojciech J. Miloch, Therese Moretto-Jørgensen, Dimitris Mpaloukidis, Nils Olsen, Konstantinos Papadakis, Robert Pfaff, Panagiotis Pirnaris, Christian Siemes, Claudia Stolle, Jonas Suni, Jose van den IJssel, Pekka T. Verronen, Pieter Visser, and Masatoshi Yamauchi
Ann. Geophys., 39, 189–237, https://doi.org/10.5194/angeo-39-189-2021, https://doi.org/10.5194/angeo-39-189-2021, 2021
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This is a review paper that summarises the current understanding of the lower thermosphere–ionosphere (LTI) in terms of measurements and modelling. The LTI is the transition region between space and the atmosphere and as such of tremendous importance to both the domains of space and atmosphere. The paper also serves as the background for European Space Agency Earth Explorer 10 candidate mission Daedalus.
Herbert Gunell, Charlotte Goetz, Elias Odelstad, Arnaud Beth, Maria Hamrin, Pierre Henri, Fredrik L. Johansson, Hans Nilsson, and Gabriella Stenberg Wieser
Ann. Geophys., 39, 53–68, https://doi.org/10.5194/angeo-39-53-2021, https://doi.org/10.5194/angeo-39-53-2021, 2021
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When the magnetised solar wind meets the plasma surrounding a comet, the magnetic field is enhanced in front of the comet, and the field lines are draped around it. This happens because electric currents are induced in the plasma. When these currents flow through the plasma, they can generate waves. In this article we present observations of ion acoustic waves, which is a kind of sound wave in the plasma, detected by instruments on the Rosetta spacecraft near comet 67P/Churyumov–Gerasimenko.
Masatoshi Yamauchi, Magnar G. Johnsen, Carl-Fredrik Enell, Anders Tjulin, Anna Willer, and Dmitry A. Sormakov
Ann. Geophys., 38, 1159–1170, https://doi.org/10.5194/angeo-38-1159-2020, https://doi.org/10.5194/angeo-38-1159-2020, 2020
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The paper reports a new finding on space weather effects at around 70–75 ° geographic latitudes. We found that X flares cause an unexpectedly strong ionospheric current driven by solar flares. The effect is as large as a substorm that is known to cause strong auroras and may enhance ongoing substorms. However, it has been overlooked in the past due to the narrow latitudinal range at high latitudes. Since severe magnetic storms often occur with X flares, this may cause geomagnetic hazards.
Markus Battarbee, Xóchitl Blanco-Cano, Lucile Turc, Primož Kajdič, Andreas Johlander, Vertti Tarvus, Stephen Fuselier, Karlheinz Trattner, Markku Alho, Thiago Brito, Urs Ganse, Yann Pfau-Kempf, Mojtaba Akhavan-Tafti, Tomas Karlsson, Savvas Raptis, Maxime Dubart, Maxime Grandin, Jonas Suni, and Minna Palmroth
Ann. Geophys., 38, 1081–1099, https://doi.org/10.5194/angeo-38-1081-2020, https://doi.org/10.5194/angeo-38-1081-2020, 2020
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We investigate the dynamics of helium in the foreshock, a part of near-Earth space found upstream of the Earth's bow shock. We show how the second most common ion in interplanetary space reacts strongly to plasma waves found in the foreshock. Spacecraft observations and supercomputer simulations both give us a new understanding of the foreshock edge and how to interpret future observations.
Audrey Schillings, Herbert Gunell, Hans Nilsson, Alexandre De Spiegeleer, Yusuke Ebihara, Lars G. Westerberg, Masatoshi Yamauchi, and Rikard Slapak
Ann. Geophys., 38, 645–656, https://doi.org/10.5194/angeo-38-645-2020, https://doi.org/10.5194/angeo-38-645-2020, 2020
Short summary
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The Earth's atmosphere is constantly losing molecules and charged particles, amongst them oxygen ions or O+. Quantifying this loss provides information about the evolution of the atmosphere on geological timescales. In this study, we investigate the final destination of O+ observed with Cluster satellites in a high-altitude magnetospheric region (plasma mantle) by tracing the particles forward in time using simulations. We find that approximately 98 % of O+ escapes the Earth's magnetosphere.
Patrik Krcelic, Stein Haaland, Lukas Maes, Rikard Slapak, and Audrey Schillings
Ann. Geophys., 38, 491–505, https://doi.org/10.5194/angeo-38-491-2020, https://doi.org/10.5194/angeo-38-491-2020, 2020
Short summary
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In this paper we have used Cluster EDI data in combination with the CODIF cusp dataset from Slapak et al. (2017) to obtain parallel and convection velocities for oxygen ions; 69 % of total oxygen outflow from the high-altitude cusps escapes the magnetosphere on average; 50 % escapes tailward beyond the distant X-line. The oxygen capture-versus-escape ratio is highly dependent on geomagnetic conditions. During active conditions, the majority of oxygen outflow is convected to the plasma sheet.
Martin Volwerk, Charlotte Goetz, Ferdinand Plaschke, Tomas Karlsson, Daniel Heyner, and Brian Anderson
Ann. Geophys., 38, 51–60, https://doi.org/10.5194/angeo-38-51-2020, https://doi.org/10.5194/angeo-38-51-2020, 2020
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The magnetic field that is carried by the solar wind slowly decreases in strength as it moves further from the Sun. However, there are sometimes localized decreases in the magnetic field strength, called magnetic holes. These are small structures where the magnetic field strength decreases to less than 50 % of the surroundings and the plasma density increases. This paper presents a statistical study of the behaviour of these holes between Mercury and Venus using MESSENGER data.
Masatoshi Yamauchi
Ann. Geophys., 37, 1197–1222, https://doi.org/10.5194/angeo-37-1197-2019, https://doi.org/10.5194/angeo-37-1197-2019, 2019
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Terrestrial ion transport and total escape are synthesized, with stress on the high-latitude polar region and the inner magnetosphere where Custer significantly improved knowledge. After estimating the outflow flux and destinations, complicated ion dynamics in the inner magnetosphere was classified and summarized, through which more than half the O+ is finally lost to space. Together with direct escapes, total O+ escape is high enough to influence the evolution of the biosphere.
Minna Palmroth, Heli Hietala, Ferdinand Plaschke, Martin Archer, Tomas Karlsson, Xóchitl Blanco-Cano, David Sibeck, Primož Kajdič, Urs Ganse, Yann Pfau-Kempf, Markus Battarbee, and Lucile Turc
Ann. Geophys., 36, 1171–1182, https://doi.org/10.5194/angeo-36-1171-2018, https://doi.org/10.5194/angeo-36-1171-2018, 2018
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Magnetosheath jets are high-velocity plasma structures that are commonly observed within the Earth's magnetosheath. Previously, they have mainly been investigated with spacecraft observations, which do not allow us to infer their spatial sizes, temporal evolution, or origin. This paper shows for the first time their dimensions, evolution, and origins within a simulation whose dimensions are directly comparable to the Earth's magnetosphere. The results are compared to previous observations.
Tomas Karlsson, Ferdinand Plaschke, Heli Hietala, Martin Archer, Xóchitl Blanco-Cano, Primož Kajdič, Per-Arne Lindqvist, Göran Marklund, and Daniel J. Gershman
Ann. Geophys., 36, 655–677, https://doi.org/10.5194/angeo-36-655-2018, https://doi.org/10.5194/angeo-36-655-2018, 2018
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We have studied fast plasma jets outside of Earth’s magnetic environment. Such jets are small-scale structures with a limited lifetime, which may be important in determining the properties of the near-Earth space environment, due to their concentrated kinetic energy. We have used data from the NASA Magnetospheric MultiScale (MMS) satellites to study their properties in detail, to understand how these jets are formed. We have found evidence that there are at least two different types of jets.
Masatoshi Yamauchi and Rikard Slapak
Ann. Geophys., 36, 1–12, https://doi.org/10.5194/angeo-36-1-2018, https://doi.org/10.5194/angeo-36-1-2018, 2018
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Extraction of the solar wind kinetic energy (∆K) by mass loading of escaping O+ is modelled in the exterior cusp and plasma mantle of the Earth. We found ∆K proportional to mass flux of escaping ions and square of solar wind velocity, but independent to the other parameters. The amount is sufficient to power the cusp field-aligned currents, further enhancing ion escape through Joule heating of the ionospheric ions, completing positive feedback to enhance escape with geomagnetic activities.
Audrey Schillings, Hans Nilsson, Rikard Slapak, Masatoshi Yamauchi, and Lars-Göran Westerberg
Ann. Geophys., 35, 1341–1352, https://doi.org/10.5194/angeo-35-1341-2017, https://doi.org/10.5194/angeo-35-1341-2017, 2017
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The Earth's atmosphere is constantly losing ions and in particular oxygen ions. This phenomenon is important to understand the atmospheric evolution on a large timescale. In this study, the O+ outflow is estimated during six extreme geomagnetic storms using the European Cluster mission data. These estimations are compared with average magnetospheric conditions and show that during those six extreme storms, the O+ outflow is approximately 2 orders of magnitude higher.
Elisabet Liljeblad and Tomas Karlsson
Ann. Geophys., 35, 879–884, https://doi.org/10.5194/angeo-35-879-2017, https://doi.org/10.5194/angeo-35-879-2017, 2017
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MESSENGER magnetic field data from the magnetosphere of Mercury have been investigated to identify ultra-low-frequency (ULF) waves. ULF waves in the Kelvin–Helmholtz (KH) wave frequency range are frequently observed in the magnetosphere. These ULF waves often have similar characteristics to previously identified, likely KH-driven ULF waves, indicating that ULF waves in a specific frequency band can be used as a detection tool for KH waves on Mercury.
Rikard Slapak, Audrey Schillings, Hans Nilsson, Masatoshi Yamauchi, Lars-Göran Westerberg, and Iannis Dandouras
Ann. Geophys., 35, 721–731, https://doi.org/10.5194/angeo-35-721-2017, https://doi.org/10.5194/angeo-35-721-2017, 2017
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In this study, we have used Cluster satellite data to quantify the ionospheric oxygen ion (O+) escape into the solar wind and its dependence on geomagnetic activity. During times of high activity, the escape may be 2 orders of magnitude higher than under quiet conditions, strongly suggesting that the escape rate was much higher when the Sun was young. The results are important for future studies regarding atmospheric loss over geological timescales.
M. Volwerk, I. Richter, B. Tsurutani, C. Götz, K. Altwegg, T. Broiles, J. Burch, C. Carr, E. Cupido, M. Delva, M. Dósa, N. J. T. Edberg, A. Eriksson, P. Henri, C. Koenders, J.-P. Lebreton, K. E. Mandt, H. Nilsson, A. Opitz, M. Rubin, K. Schwingenschuh, G. Stenberg Wieser, K. Szegö, C. Vallat, X. Vallieres, and K.-H. Glassmeier
Ann. Geophys., 34, 1–15, https://doi.org/10.5194/angeo-34-1-2016, https://doi.org/10.5194/angeo-34-1-2016, 2016
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The solar wind magnetic field drapes around the active nucleus of comet 67P/CG, creating a magnetosphere. The solar wind density increases and with that the pressure, which compresses the magnetosphere, increasing the magnetic field strength near Rosetta. The higher solar wind density also creates more ionization through collisions with the gas from the comet. The new ions are picked-up by the magnetic field and generate mirror-mode waves, creating low-field high-density "bottles" near 67P/CG.
I. Richter, C. Koenders, H.-U. Auster, D. Frühauff, C. Götz, P. Heinisch, C. Perschke, U. Motschmann, B. Stoll, K. Altwegg, J. Burch, C. Carr, E. Cupido, A. Eriksson, P. Henri, R. Goldstein, J.-P. Lebreton, P. Mokashi, Z. Nemeth, H. Nilsson, M. Rubin, K. Szegö, B. T. Tsurutani, C. Vallat, M. Volwerk, and K.-H. Glassmeier
Ann. Geophys., 33, 1031–1036, https://doi.org/10.5194/angeo-33-1031-2015, https://doi.org/10.5194/angeo-33-1031-2015, 2015
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We present a first report on magnetic field measurements made in the coma of comet 67P/C-G in its low-activity state. The plasma environment is dominated by quasi-coherent, large-amplitude, compressional magnetic field oscillations around 40mHz, differing from the observations at strongly active comets where waves at the cometary ion gyro-frequencies are the main feature. We propose a cross-field current instability associated with the newborn cometary ions as a possible source mechanism.
R. Slapak, H. Nilsson, L. G. Westerberg, and R. Larsson
Ann. Geophys., 33, 301–307, https://doi.org/10.5194/angeo-33-301-2015, https://doi.org/10.5194/angeo-33-301-2015, 2015
T. Pitkänen, M. Hamrin, P. Norqvist, T. Karlsson, H. Nilsson, A. Kullen, S. M. Imber, and S. E. Milan
Ann. Geophys., 33, 245–255, https://doi.org/10.5194/angeo-33-245-2015, https://doi.org/10.5194/angeo-33-245-2015, 2015
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An azimuthal velocity shear with a reversal within an earthward magnetotail fast flow is studied using Cluster observations. In addition, ionospheric SuperDARN data and different magnetospheric models (T96 and TF04) are utilized when interpreting the Cluster observations. Untwisting of twisted tail B field lines is a good candidate to explain the observations.
I. A. Barghouthi, H. Nilsson, and S. H. Ghithan
Ann. Geophys., 32, 1043–1057, https://doi.org/10.5194/angeo-32-1043-2014, https://doi.org/10.5194/angeo-32-1043-2014, 2014
H. Gunell, G. Stenberg Wieser, M. Mella, R. Maggiolo, H. Nilsson, F. Darrouzet, M. Hamrin, T. Karlsson, N. Brenning, J. De Keyser, M. André, and I. Dandouras
Ann. Geophys., 32, 991–1009, https://doi.org/10.5194/angeo-32-991-2014, https://doi.org/10.5194/angeo-32-991-2014, 2014
K. Axelsson, T. Sergienko, H. Nilsson, U. Brändström, K. Asamura, and T. Sakanoi
Ann. Geophys., 32, 499–506, https://doi.org/10.5194/angeo-32-499-2014, https://doi.org/10.5194/angeo-32-499-2014, 2014
M. Yamauchi, Y. Ebihara, H. Nilsson, and I. Dandouras
Ann. Geophys., 32, 83–90, https://doi.org/10.5194/angeo-32-83-2014, https://doi.org/10.5194/angeo-32-83-2014, 2014
M. Yamauchi, I. Dandouras, H. Rème, R. Lundin, and L. M. Kistler
Ann. Geophys., 31, 1569–1578, https://doi.org/10.5194/angeo-31-1569-2013, https://doi.org/10.5194/angeo-31-1569-2013, 2013
A. T. Aikio, T. Pitkänen, I. Honkonen, M. Palmroth, and O. Amm
Ann. Geophys., 31, 1021–1034, https://doi.org/10.5194/angeo-31-1021-2013, https://doi.org/10.5194/angeo-31-1021-2013, 2013
R. Slapak, H. Nilsson, and L. G. Westerberg
Ann. Geophys., 31, 1005–1010, https://doi.org/10.5194/angeo-31-1005-2013, https://doi.org/10.5194/angeo-31-1005-2013, 2013
S. Kirkwood, E. Belova, P. Dalin, M. Mihalikova, D. Mikhaylova, D. Murtagh, H. Nilsson, K. Satheesan, J. Urban, and I. Wolf
Ann. Geophys., 31, 333–347, https://doi.org/10.5194/angeo-31-333-2013, https://doi.org/10.5194/angeo-31-333-2013, 2013
I. Mann and M. Hamrin
Ann. Geophys., 31, 39–44, https://doi.org/10.5194/angeo-31-39-2013, https://doi.org/10.5194/angeo-31-39-2013, 2013
K. Axelsson, T. Sergienko, H. Nilsson, U. Brändström, Y. Ebihara, K. Asamura, and M. Hirahara
Ann. Geophys., 30, 1693–1701, https://doi.org/10.5194/angeo-30-1693-2012, https://doi.org/10.5194/angeo-30-1693-2012, 2012
Short summary
The ion total transports in the near-Earth plasma sheet have been investigated and quantified. Specifically, the net O+ transport is about 1024 s−1 in the earthward direction, which is 1 order of magnitude smaller than the typical O+ ionospheric outflows, strongly indicating that most outflow will eventually escape, leading to significant atmospheric loss. The study also shows that low-velocity flows (< 100 km s−1) dominate the mass transport in the near-Earth plasma sheet.
The ion total transports in the near-Earth plasma sheet have been investigated and quantified....