Search

Your search keyword '"N. Fargette"' showing total 10 results
Start Over Author "N. Fargette" Language undetermined
10 results on '"N. Fargette"'

3. Investigation of the Diamagnetic Drift Condition for the Suppression of Magnetic Reconnection in 3D Interlinked Reconnection Events with Magnetic Flux Pileup

Author

K. Maheshwari, T. D. Phan, M. Øieroset, N. Fargette, B. Lavraud, J. L. Burch, R. J. Strangeway, D. J. Gershman, and B. L. Giles

Subjects
Space and Planetary Science, Astronomy and Astrophysics
Abstract

We have performed a statistical survey to investigate possible diamagnetic drift suppression of magnetic reconnection using Magnetospheric Multiscale observations of interlinked magnetic field line events at Earth’s magnetopause. Our goal is to investigate a possible cause for the observed magnetic field pileup on the two sides of the thin reconnecting current sheets, at the interface of the converging field lines. We compare whether the diamagnetic drift condition for the suppression of reconnection is satisfied before and after magnetic field pileup. We find that for a majority of events in our data set, the pre-pileup plasma β gradient and magnetic shear values were in the reconnection-suppressed regime, whereas the post-pileup values were in the reconnection-allowed regime. A possible interpretation is that reconnection was suppressed under the pre-pileup conditions, and this led to magnetic field pileup. The magnetic field pileup subsequently generated boundary conditions at the interlinked current sheet that overcame the diamagnetic drift suppression condition, allowing reconnection to happen in the interlinked field line structure. However, in one third of the events, the pre-pileup conditions were already in the reconnection-allowed regime, indicating that in such events, the diamagnetic suppression condition was probably not responsible for field pileup.

Published
2022
Full Text
View/download PDF

4. Evolution of coronal hole solar wind in the inner heliosphere: Combined observations by Solar Orbiter and Parker Solar Probe

Author

D. Perrone, S. Perri, R. Bruno, D. Stansby, R. D’Amicis, V. K. Jagarlamudi, R. Laker, S. Toledo-Redondo, J. E. Stawarz, D. Telloni, R. De Marco, C. J. Owen, J. M. Raines, A. Settino, B. Lavraud, M. Maksimovic, A. Vaivads, T. D. Phan, N. Fargette, P. Louarn, and I. Zouganelis

Subjects
Space and Planetary Science, Astronomy and Astrophysics
Abstract

We study the radial evolution, from 0.1 AU to the Earth, of a homogeneous recurrent fast wind, coming from the same source on the Sun, by means of new measurements by both Solar Orbiter and Parker Solar Probe. With respect to previous radial studies, we extend, for the first time, the analysis of a recurrent fast stream at distances never reached prior to the Parker Solar Probe mission. Confirming previous findings, the observations show: (i) a decrease in the radial trend of the proton density that is slower than the one expected for a radially expanding plasma, due to the possible presence of a secondary beam in the velocity distribution function; (ii) a deviation for the magnetic field from the Parker prediction, supported by the strong Alfvénicity of the stream at all distances; and (iii) a slower decrease in the proton temperature with respect to the adiabatic prediction, suggesting the local presence of external heating mechanisms. Focusing on the radial evolution of the turbulence, from the inertial to the kinetic range along the turbulent cascade, we find that the slopes, in both frequency ranges, strongly depend on the different turbulence observed by the two spacecraft, namely a mostly parallel turbulence in the Parker Solar Probe data and a mostly perpendicular turbulence in the Solar Orbiter intervals. Moreover, we observe a decrease in the level of intermittency for the magnetic field during the expansion of the stream. Furthermore, we perform, for the first time, a statistical analysis of coherent structures around proton scales at 0.1 AU and we study how some of their statistical properties change from the Sun to the Earth. As expected, we find a higher occurrence of events in the Parker Solar Probe measurements than in the Solar Orbiter data, considering the ratio between the intervals length and the proton characteristic scales at the two radial distances. Finally, we complement this statistical analysis with two case studies of current sheets and vortex-like structures detected at the two radial distances, and we find that structures that belong to the same family have similar characteristics at different radial distances. This work provides an insight into the radial evolution of the turbulent character of solar wind plasma coming from coronal holes.

Published
2022
Full Text
View/download PDF

5. Solar Orbiter observations of magnetic Kelvin-Helmholtz waves in the solar wind

Author

Evans, A. P. Rouillard, Emmanuel Penou, N. Fargette, Timothy S. Horbury, Angelini, Helen O'Brien, Benoit Lavraud, Y. Yang, David Ruffolo, Andrei Fedorov, S. Aizawa, Claire Foullon, Génot, R. Kieokaew, Julia E. Stawarz, P. Louarn, Rui Pinto, Christopher J. Owen, and William H. Matthaeus

Subjects
Physics, Orbiter, symbols.namesake, Solar wind, law, Helmholtz free energy, Physics::Space Physics, symbols, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Geophysics, Heliosphere, law.invention
Abstract

The Kelvin-Helmholtz instability (KHI) is a nonlinear shear-driven instability that develops at the interfaces between shear flows in plasmas. KHI is ubiquitous in plasmas and has been observed in situ at planetary interfaces and at the boundaries of coronal mass ejections in remote-sensing observations. KHI is also expected to develop at flow shear interfaces in the solar wind, but while it was hypothesized to play an important role in the mixing of plasmas and exciting solar wind fluctuations, its direct observation in the solar wind was still lacking. We report first in-situ observations of ongoing KHI in the solar wind using Solar Orbiter during its cruise phase. The KHI is found in a shear layer in the slow solar wind near the Heliospheric Current Sheet. We find that the observed conditions satisfy the KHI onset criterion from linear theory and the steepening of the shear boundary layer is consistent with the development of KH vortices. We further investigate the solar wind source of this event to understand the conditions that support KH growth. In addition, we set up a local MHD simulation using the empirical values to reproduce the observed KHI. This observed KHI in the solar wind provides robust evidence that shear instability develops in the solar wind, with obvious implications in the driving of solar wind fluctuations and turbulence. The reasons for the lack of previous such measurements are also discussed.

Published
2021
Full Text
View/download PDF

7. On the Ubiquity of Magnetic Reconnection Inside Flux Transfer Event‐Like Structures at the Earth's Magnetopause

Author

Michael O. Chandler, Elena Grigorenko, S. M. Petrinec, Hiroshi Hasegawa, Charlie J. Farrugia, Victoria N. Coffey, W. R. Paterson, C. Schiff, John C. Dorelli, Thomas E. Moore, Marit Øieroset, S. Fadanelli, K. J. Trattner, Sergio Toledo-Redondo, Jonathan Eastwood, S. A. Fuselier, T. D. Phan, C. J. Pollock, J. A. Sauvaud, Benoit Lavraud, Yoshitaka Saito, Q. Lenouvel, C. Jacquey, Philippe Garnier, James L. Burch, D. J. Gershman, R. Kieokaew, N. Fargette, D. L. A. Avanov, S. E. Smith, Vincent Génot, Emmanuel Penou, Barbara L. Giles, Science and Technology Facilities Council (STFC), 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), Space Sciences Laboratory [Berkeley] (SSL), University of California [Berkeley], University of California-University of California, Centre de physique moléculaire optique et hertzienne (CPMOH), Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1, Space Science Division [San Antonio], Southwest Research Institute [San Antonio] (SwRI), Lockheed Martin Advanced Technology Center (ATC), Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency [Sagamihara] (JAXA), Laboratoire de microbiologie et génétique moléculaires (LMGM), Centre de Biologie Intégrative (CBI), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), NASA Goddard Space Flight Center (GSFC), Laboratoire de Parasitologie-Mycologie, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Henri Mondor-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), NASA Headquarters, Space Research Institute of the Russian Academy of Sciences (IKI), Russian Academy of Sciences [Moscow] (RAS), Hokkaido University [Sapporo, Japan], Centre d'Immunologie de Marseille - Luminy (CIML), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Joint Global Change Research Institute, Pacific Northwest National Laboratory (PNNL)-University of Maryland [College Park], University of Maryland System-University of Maryland System, 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), University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), Université Sciences et Technologies - Bordeaux 1 (UB)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de microbiologie et génétique moléculaires - UMR5100 (LMGM), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-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), Université Sciences et Technologies - Bordeaux 1-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), and Génot, Vincent

Subjects
Physics, 010504 meteorology & atmospheric sciences, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Magnetic reconnection, Geophysics, 01 natural sciences, Physics::Space Physics, 0103 physical sciences, Meteorology & Atmospheric Sciences, General Earth and Planetary Sciences, Magnetopause, Flux transfer event, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Earth (classical element), 0105 earth and related environmental sciences
Abstract

Flux transfer events (FTEs) are transient phenomena frequently observed at the Earth's magnetopause. Their usual interpretation is a flux rope moving away from the reconnection region. However, the Magnetospheric Multiscale Mission revealed that magnetic reconnection sometimes occurs inside these structures, questioning their flux rope configuration. Here we investigate 229 FTE‐type structures and find reconnection signatures inside 19% of them. We analyze their large‐scale magnetic topology using electron heat flux and find that it is significantly different across the FTE reconnecting current sheets, demonstrating that they are constituted of two magnetically disconnected structures. We also find that the interplanetary magnetic field (IMF) associated with reconnecting FTEs presents a strong By component. We discuss several formation mechanisms to explain these observations. In particular, the maximum magnetic shear model predicts that for large IMF By, two spatially distinct X lines coexist at the magnetopause. They can generate separate magnetic flux tubes that may become interlaced.

Published
2020
Full Text
View/download PDF

8. Flux rope and dynamics of the heliospheric current sheet

Author

V. Réville, N. Fargette, A. P. Rouillard, B. Lavraud, M. Velli, A. Strugarek, S. Parenti, A. S. Brun, C. Shi, A. Kouloumvakos, N. Poirier, R. F. Pinto, P. Louarn, A. Fedorov, C. J. Owen, V. Génot, T. S. Horbury, R. Laker, H. O’Brien, V. Angelini, E. Fauchon-Jones, J. C. Kasper, Science and Technology Facilities Council (STFC), 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), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Travaux et recherches archéologiques sur les cultures, les espaces et les sociétés (TRACES), École des hautes études en sciences sociales (EHESS)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université de Toulouse (UT)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Department of Physics [Imperial College London], and Imperial College London

Subjects
astro-ph.SR, data analysis, Astronomy & Astrophysics, NULL POINTS, magnetohydrodynamics (MHD), CORONA, methods: numerical, methods, numerical, physics.plasm-ph, 0201 Astronomical and Space Sciences, Astrophysics::Solar and Stellar Astrophysics, Science & Technology, 3-DIMENSIONAL MAGNETIC RECONNECTION, SUN, Astronomy and Astrophysics, WIND, methods: data analysis, solar wind, Space and Planetary Science, magnetic reconnection, Physical Sciences, Physics::Space Physics, TURBULENCE, Astrophysics::Earth and Planetary Astrophysics, MAGNETOHYDRODYNAMIC MODELS, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

Context. Solar Orbiter and Parker Solar Probe jointly observed the solar wind for the first time in June 2020, capturing data from very different solar wind streams: calm, Alfvénic wind and also highly dynamic large-scale structures. Context. Our aim is to understand the origin and characteristics of the highly dynamic solar wind observed by the two probes, particularly in the vicinity of the heliospheric current sheet (HCS). Methods. We analyzed the plasma data obtained by Parker Solar Probe and Solar Orbiter in situ during the month of June 2020. We used the Alfvén-wave turbulence magnetohydrodynamic solar wind model WindPredict-AW and we performed two 3D simulations based on ADAPT solar magnetograms for this period. Results. We show that the dynamic regions measured by both spacecraft are pervaded by flux ropes close to the HCS. These flux ropes are also present in the simulations, forming at the tip of helmet streamers, that is, at the base of the heliospheric current sheet. The formation mechanism involves a pressure-driven instability followed by a fast tearing reconnection process. We further characterize the 3D spatial structure of helmet streamer born flux ropes, which appears in the simulations to be related to the network of quasi-separatrices.

Published
2022
Full Text
View/download PDF

9. Solar Orbiter observations of the Kelvin-Helmholtz waves in the solar wind

Author

Y. Yang, David Ruffolo, Julia E. Stawarz, N. Fargette, William H. Matthaeus, Andrei Fedorov, Vincent Génot, Helen O'Brien, P. Louarn, Christopher J. Owen, R. Kieokaew, A. P. Rouillard, Claire Foullon, S. Aizawa, Vincent Evans, V. Angelini, Emmanuel Penou, Timothy S. Horbury, Rui Pinto, Benoit Lavraud, 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), Harvard University [Cambridge], University of Warwick [Coventry], 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), Harvard University, Science and Technology Facilities Council (STFC), and The Royal Society

Subjects
astro-ph.SR, TANGENTIAL DISCONTINUITIES, 010504 meteorology & atmospheric sciences, INSTABILITY, MAGNETOPAUSE, SURFACE-WAVES, Astrophysics, Astronomy & Astrophysics, magnetohydrodynamics (MHD), 01 natural sciences, methods, law.invention, Orbiter, symbols.namesake, law, physics.plasm-ph, RECONNECTION, 0201 Astronomical and Space Sciences, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, observational, Sun: heliosphere, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, Science & Technology, PLASMA, Computer Science::Information Retrieval, Sun, heliosphere, Astronomy, Astronomy and Astrophysics, MAGNETIC SHEAR, CURRENT SHEETS, plasmas, Solar wind, solar wind, physics.space-ph, instabilities, 13. Climate action, Space and Planetary Science, Helmholtz free energy, Physical Sciences, DIRECTIONAL DISCONTINUITIES, Physics::Space Physics, symbols, TURBULENCE, methods: observational, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

Context.The Kelvin-HeImholtz (KH) instability is a nonlinear shear-driven instability that develops at the interface between shear flows in plasmas. KH waves have been inferred in various astrophysical plasmas, and have been observed in situ at the magnetospheric boundaries of solar-system planets and through remote sensing at the boundaries of coronal mass ejections.Aims.KH waves are also expected to develop at flow shear interfaces in the solar wind. While they were hypothesized to play an important role in the mixing of plasmas and in triggering solar wind fluctuations, their direct and unambiguous observation in the solar wind was still lacking.Methods.We report in situ observations of quasi-periodic magnetic and velocity field variations plausibly associated with KH waves using Solar Orbiter during its cruise phase. They are found in a shear layer in the slow solar wind in the close vicinity of the heliospheric current sheet. An analysis was performed to derive the local configuration of the waves. A 2D magnetohydrodynamics simulation was also set up with approximate empirical values to test the stability of the shear layer. In addition, magnetic spectra of the event were analyzed.Results.We find that the observed conditions satisfy the KH instability onset criterion from the linear theory analysis, and its development is further confirmed by the simulation. The current sheet geometry analyses are found to be consistent with KH wave development, albeit with some limitations likely owing to the complex 3D nature of the event and solar wind propagation. Additionally, we report observations of an ion jet consistent with magnetic reconnection at a compressed current sheet within the KH wave interval. The KH activity is found to excite magnetic and velocity fluctuations with power law scalings that approximately followk−5/3andk−2.8in the inertial and dissipation ranges, respectively. Finally, we discuss reasons for the lack of in situ KH wave detection in past data.Conclusions.These observations provide robust evidence of KH wave development in the solar wind. This sheds new light on the process of shear-driven turbulence as mediated by the KH waves with implications for the driving of solar wind fluctuations.

Published
2021
Full Text
View/download PDF

10. Magnetic increases with central current sheets: observations with Parker Solar Probe

Author

T. D. Phan, Stuart D. Bale, Davin Larson, John W. Bonnell, Jasper Halekas, Michael L. Stevens, Matthieu Berthomier, David M. Malaspina, Marit Øieroset, Jonathan Eastwood, Peter Harvey, Benoit Lavraud, Marc Pulupa, A. P. Rouillard, N. Fargette, Kelly E. Korreck, Phyllis Whittlesey, Keith Goetz, Justin C. Kasper, Philippe Louarn, A. W. Case, Robert J. MacDowall, T. Dudok de Wit, Science and Technology Facilities Council (STFC), 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), Department of Physics [Imperial College London], Imperial College London, Space Sciences Laboratory [Berkeley] (SSL), University of California [Berkeley], University of California-University of California, Department of Physics and Astronomy [Iowa City], University of Iowa [Iowa City], Department of Climate and Space Sciences and Engineering (CLaSP), University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Smithsonian Astrophysical Observatory, Smithsonian Institution, University of Colorado [Boulder], GSFC Solar System Exploration Division, NASA Goddard Space Flight Center (GSFC), School of Physics and Astronomy [Minneapolis], University of Minnesota [Twin Cities] (UMN), University of Minnesota System-University of Minnesota System, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), 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), University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES)

Subjects
Physics, 010504 meteorology & atmospheric sciences, Astronomy and Astrophysics, Magnetic reconnection, Astrophysics, Astronomy & Astrophysics, 01 natural sciences, Magnetic field, Strahl, Current sheet, Solar wind, 13. Climate action, Space and Planetary Science, Physics::Space Physics, 0201 Astronomical and Space Sciences, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Magnetopause, Heliospheric current sheet, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Interplanetary spaceflight, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences
Abstract

Aims.We report the observation by Parker Solar Probe (PSP) of magnetic structures in the solar wind that present a strong peak in their magnetic field magnitude with an embedded central current sheet. Similar structures have been observed, either at the Earth’s magnetopause and called interlinked flux tubes, or in the solar wind and called interplanetary field enhancements.Methods.In this work, we first investigate two striking events in detail; one occurred in the regular slow solar wind on November 2, 2018 and the other was observed during a heliospheric current sheet crossing on November 13, 2018. They both show the presence of a central current sheet with a visible ion jet and general characteristics consistent with the occurrence of magnetic reconnection. We then performed a survey of PSP data from encounters 1 to 4 and find 18 additional events presenting an increase in the magnetic field magnitude of over 30% and a central current sheet. We performed a statistical study on the 20 “magnetic increases with central current sheet” (MICCS), with 13 observed in the regular slow solar wind with a constant polarity (i.e., identical strahl direction), and 7 which were specifically observed near a heliospheric current sheet crossing.Results.We analyze and discuss the general properties of the structures, including the duration, location, amplitude, and magnetic topology, as well as the characteristics of their central current sheet. We find that the latter has a preferential orientation in the TN plane of the RTN frame. We also find no significant change in the dust impact rate in the vicinity of the MICCS under study, leading us to conclude that dust probably plays no role in the MICCS formation and evolution. Our findings are overall consistent with a double flux tube-configuration that would result from initially distinct flux tubes which interact during solar wind propagation.

Published
2021
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results