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Zhou Y, Raptis S, Wang S, Shen C, Ren N, Ma L. Magnetosheath jets at Jupiter and across the solar system. Nat Commun 2024; 15:4. [PMID: 38195592 PMCID: PMC10776788 DOI: 10.1038/s41467-023-43942-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 11/23/2023] [Indexed: 01/11/2024] Open
Abstract
The study of jets in the Earth's magnetosheath has been a subject of extensive investigation for over a decade due to their profound impact on the geomagnetic environment and their close connection with shock dynamics. While the variability of the solar wind and its interaction with Earth's magnetosphere provide valuable insights into jets across a range of parameters, a broader parameter space can be explored by examining the magnetosheath of other planets. Here we report the existence of anti-sunward and sunward jets in the Jovian magnetosheath and show their close association with magnetic discontinuities. The anti-sunward jets are possibly generated by a shock-discontinuity interaction. Finally, through a comparative analysis of jets observed at Earth, Mars, and Jupiter, we show that the size of jets scales with the size of bow shock.
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Affiliation(s)
- Yufei Zhou
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, China
| | - Savvas Raptis
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD, USA
| | - Shan Wang
- Institute of Space Physics and Applied Technology, Peking University, Beijing, China
| | - Chao Shen
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, China.
| | - Nian Ren
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, China
- School of Physics and Electronic Science, Hunan Institute of Science and Technology, Yueyang, China
| | - Lan Ma
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, China
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2
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Vuorinen L, LaMoury AT, Hietala H, Koller F. Magnetosheath Jets Over Solar Cycle 24: An Empirical Model. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2023; 128:e2023JA031493. [PMID: 38440390 PMCID: PMC10909464 DOI: 10.1029/2023ja031493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 06/15/2023] [Accepted: 07/10/2023] [Indexed: 03/06/2024]
Abstract
Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft have been sampling the subsolar magnetosheath since the first dayside science phase in 2008, and we finally have observations over a solar cycle. However, we show that the solar wind coverage during these magnetosheath intervals is not always consistent with the solar wind conditions throughout the same year. This has implications for studying phenomena whose occurrence depends strongly on solar wind parameters. We demonstrate this with magnetosheath jets-flows of enhanced earthward dynamic pressure in the magnetosheath. Jets emerge from the bow shock, and some of them can go on and collide into the magnetopause. Their occurrence is highly linked to solar wind conditions, particularly the orientation of the interplanetary magnetic field, as jets are mostly observed downstream of the quasi-parallel shock. We study the yearly occurrence rates of jets recorded by THEMIS over solar cycle 24 (2008-2019) and find that they are biased due to differences in spacecraft orbits and uneven sampling of solar wind conditions during the different years. Thus, we instead use the THEMIS observations and their corresponding solar wind conditions to develop a model of how jet occurrence varies as a function of solar wind conditions. We then use OMNI data of the whole solar cycle to estimate the unbiased yearly jet occurrence rates. For comparison, we also estimate jet occurrence rates during solar cycle 23 (1996-2008). Our results suggest that there is no strong solar cycle dependency in jet formation.
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Affiliation(s)
- Laura Vuorinen
- Department of Physics and AstronomyUniversity of TurkuTurkuFinland
| | | | - Heli Hietala
- Department of Physics and AstronomyUniversity of TurkuTurkuFinland
- Blackett LaboratoryImperial College LondonLondonUK
- Department of Physics and AstronomyQueen Mary University of LondonLondonUK
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3
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Blanco‐Cano X, Rojas‐Castillo D, Kajdič P, Preisser L. Jets and Mirror Mode Waves in Earth's Magnetosheath. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2023; 128:e2022JA031221. [PMID: 38439786 PMCID: PMC10909539 DOI: 10.1029/2022ja031221] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 06/26/2023] [Accepted: 07/04/2023] [Indexed: 03/06/2024]
Abstract
Magnetosheath jets are localized plasma structures with high dynamic pressure which are frequently observed downstream of the Earth's bow shock. In this work we analyze Magnetospheric MultiScale magnetic field and plasma data and show that jets can be found in the quasi-perpendicular magnetosheath in regions permeated by Mirror mode waves (MMWs). We show that structures identified as jets by their enhanced dynamic pressure can have very different internal structure, with variable signatures in magnetic field magnitude and components, velocity, and density and can be associated to ion distribution functions of various types. This suggests that jets observed in the quasi-perpendicular magnetosheath are generated by different mechanisms. We find that jets can be related to traveling foreshocks, flux transfer events, and some have MMWs inside them. Our results suggest that some jets have a local source and their formation does not depend on upstream structures. We find that different types of ion distributions can exist inside the jets, while in some cases anisotropic distributions are present, in others counterstreaming distributions exist. We also show that for jets with MMWs inside them, ion distributions can be modulated. This highlights the importance of using ion distributions to identify and classify different types of jets.
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Affiliation(s)
- X. Blanco‐Cano
- Instituto de GeofísicaUniversidad Nacional Autónoma de MéxicoCircuito de la Investigación Científica s/nCiudad UniversitariaMexico CityMexico
| | - D. Rojas‐Castillo
- Instituto de GeofísicaUniversidad Nacional Autónoma de MéxicoCircuito de la Investigación Científica s/nCiudad UniversitariaMexico CityMexico
| | - P. Kajdič
- Instituto de GeofísicaUniversidad Nacional Autónoma de MéxicoCircuito de la Investigación Científica s/nCiudad UniversitariaMexico CityMexico
| | - L. Preisser
- Space Research InstituteAustrian Academy of SciencesGrazAustria
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Gunell H, Hamrin M, Nesbit-Östman S, Krämer E, Nilsson H. Magnetosheath jets at Mars. SCIENCE ADVANCES 2023; 9:eadg5703. [PMID: 37267367 PMCID: PMC10413640 DOI: 10.1126/sciadv.adg5703] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 04/28/2023] [Indexed: 06/04/2023]
Abstract
Plasma entities, known as magnetosheath jets, with higher dynamic pressure than the surrounding plasma, are often seen at Earth. They generate waves and contribute to energy transfer in the magnetosheath. Affecting the magnetopause, they cause surface waves and transfer energy into the magnetosphere, causing throat auroras and magnetic signatures detectable on the ground. We show that jets exist also beyond Earth's environment in the magnetosheath of Mars, using data obtained by the MAVEN spacecraft. Thus, jets can be created also at Mars, which differs from Earth by its smaller bow shock, and they are associated with an increased level of magnetic field fluctuations. Jets couple large and small scales in magnetosheaths in the solar system and can play a similar part in astrophysical plasmas.
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Affiliation(s)
- Herbert Gunell
- Department of Physics, Umeå University, 901 87 Umeå, Sweden
| | - Maria Hamrin
- Department of Physics, Umeå University, 901 87 Umeå, Sweden
| | | | - Eva Krämer
- Department of Physics, Umeå University, 901 87 Umeå, Sweden
| | - Hans Nilsson
- Swedish Institute of Space Physics, Box 812, 981 28 Kiruna, Sweden
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Koller F, Plaschke F, Temmer M, Preisser L, Roberts OW, Vörös Z. Magnetosheath Jet Formation Influenced by Parameters in Solar Wind Structures. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2023; 128:e2023JA031339. [PMID: 38440351 PMCID: PMC10909547 DOI: 10.1029/2023ja031339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 03/16/2023] [Accepted: 03/23/2023] [Indexed: 03/06/2024]
Abstract
Magnetosheath jets are dynamic pressure enhancements observed in the terrestrial magnetosheath. Their generation mechanisms are currently debated but the majority of jets can be linked to foreshock processes. Recent results showed that jets are less numerous when coronal mass ejections (CMEs) cross the magnetosheath and more numerous when stream interaction regions (SIRs) cross it. Here, we show for the first time how the pronounced substructures of CMEs and SIRs are related to jet production. We distinguish between compression and magnetic ejecta (ME) regions for the CME as well as compression region associated with the stream interface and high-speed streams (HSSs) for the SIR. Based on THEMIS and OMNI data covering 2008-2021, we show the 2D probability distribution of jet occurrence using the cone angle and Alfvén Mach number. We compare this distribution with the values within each solar wind (SW) structure. We find that both high cone angles and low Alfvén Mach numbers within CME-MEs are unfavorable for jet production as they may inhibit a well-defined foreshock region. 1D histograms of all parameters show, which SW parameters govern jet occurrence in each SW structure. In terms of the considered parameters the most favorable conditions for jet generation are found for HSSs due to their associated low cone angles, low densities, and low magnetic field strengths.
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Affiliation(s)
| | - Ferdinand Plaschke
- Institut für Geophysik und Extraterrestrische PhysikTU BraunschweigBraunschweigGermany
| | | | - Luis Preisser
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - Owen W. Roberts
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - Zoltan Vörös
- Space Research InstituteAustrian Academy of SciencesGrazAustria
- Institute of Earth Physics and Space ScienceELRNSopronHungary
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Svenningsson I, Yordanova E, Cozzani G, Khotyaintsev YV, André M. Kinetic Generation of Whistler Waves in the Turbulent Magnetosheath. GEOPHYSICAL RESEARCH LETTERS 2022; 49:e2022GL099065. [PMID: 36247519 PMCID: PMC9541185 DOI: 10.1029/2022gl099065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 07/22/2022] [Accepted: 07/27/2022] [Indexed: 06/16/2023]
Abstract
The Earth's magnetosheath (MSH) is governed by numerous physical processes which shape the particle velocity distributions and contribute to the heating of the plasma. Among them are whistler waves which can interact with electrons. We investigate whistler waves detected in the quasi-parallel MSH by NASA's Magnetospheric Multiscale mission. We find that the whistler waves occur even in regions that are predicted stable to wave growth by electron temperature anisotropy. Whistlers are observed in ion-scale magnetic minima and are associated with electrons having butterfly-shaped pitch-angle distributions. We investigate in detail one example and, with the support of modeling by the linear numerical dispersion solver Waves in Homogeneous, Anisotropic, Multicomponent Plasmas, we demonstrate that the butterfly distribution is unstable to the observed whistler waves. We conclude that the observed waves are generated locally. The result emphasizes the importance of considering complete 3D particle distribution functions, and not only the temperature anisotropy, when studying plasma wave instabilities.
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Affiliation(s)
- I. Svenningsson
- Swedish Institute of Space PhysicsUppsalaSweden
- Department of Physics and AstronomyUppsala UniversityUppsalaSweden
| | | | - G. Cozzani
- Department of PhysicsUniversity of HelsinkiHelsinkiFinland
| | | | - M. André
- Swedish Institute of Space PhysicsUppsalaSweden
- Department of Physics and AstronomyUppsala UniversityUppsalaSweden
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Zhang H, Zong Q, Connor H, Delamere P, Facskó G, Han D, Hasegawa H, Kallio E, Kis Á, Le G, Lembège B, Lin Y, Liu T, Oksavik K, Omidi N, Otto A, Ren J, Shi Q, Sibeck D, Yao S. Dayside Transient Phenomena and Their Impact on the Magnetosphere and Ionosphere. SPACE SCIENCE REVIEWS 2022; 218:40. [PMID: 35784192 PMCID: PMC9239986 DOI: 10.1007/s11214-021-00865-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Accepted: 11/11/2021] [Indexed: 06/15/2023]
Abstract
Dayside transients, such as hot flow anomalies, foreshock bubbles, magnetosheath jets, flux transfer events, and surface waves, are frequently observed upstream from the bow shock, in the magnetosheath, and at the magnetopause. They play a significant role in the solar wind-magnetosphere-ionosphere coupling. Foreshock transient phenomena, associated with variations in the solar wind dynamic pressure, deform the magnetopause, and in turn generates field-aligned currents (FACs) connected to the auroral ionosphere. Solar wind dynamic pressure variations and transient phenomena at the dayside magnetopause drive magnetospheric ultra low frequency (ULF) waves, which can play an important role in the dynamics of Earth's radiation belts. These transient phenomena and their geoeffects have been investigated using coordinated in-situ spacecraft observations, spacecraft-borne imagers, ground-based observations, and numerical simulations. Cluster, THEMIS, Geotail, and MMS multi-mission observations allow us to track the motion and time evolution of transient phenomena at different spatial and temporal scales in detail, whereas ground-based experiments can observe the ionospheric projections of transient magnetopause phenomena such as waves on the magnetopause driven by hot flow anomalies or flux transfer events produced by bursty reconnection across their full longitudinal and latitudinal extent. Magnetohydrodynamics (MHD), hybrid, and particle-in-cell (PIC) simulations are powerful tools to simulate the dayside transient phenomena. This paper provides a comprehensive review of the present understanding of dayside transient phenomena at Earth and other planets, their geoeffects, and outstanding questions.
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Affiliation(s)
- Hui Zhang
- Physics Department & Geophysical Institute, University of Alaska Fairbanks, 2156 Koyukuk Drive, Fairbanks, AK 99775 USA
- Shandong University, Weihai, China
| | - Qiugang Zong
- Institute of Space Physics and Applied Technology, Peking University, Beijing, 100871 China
- Polar Research Institute of China, Shanghai, 200136 China
| | - Hyunju Connor
- Physics Department & Geophysical Institute, University of Alaska Fairbanks, 2156 Koyukuk Drive, Fairbanks, AK 99775 USA
- NASA Goddard Space Flight Center, Greenbelt, MD 20771 USA
| | - Peter Delamere
- Physics Department & Geophysical Institute, University of Alaska Fairbanks, 2156 Koyukuk Drive, Fairbanks, AK 99775 USA
| | - Gábor Facskó
- Department of Informatics, Milton Friedman University, 1039 Budapest, Hungary
- Wigner Research Centre for Physics, Konkoly-Thege Miklós út 29-33, 1121 Budapest, Hungary
| | | | - Hiroshi Hasegawa
- Institute of Space and Astronautical Science, JAXA, Sagamihara, Japan
| | | | - Árpád Kis
- Institute of Earth Physics and Space Science (ELKH EPSS), Sopron, Hungary
| | - Guan Le
- NASA Goddard Space Flight Center, Greenbelt, MD 20771 USA
| | - Bertrand Lembège
- LATMOS (Laboratoire Atmosphères, Milieux, Observations Spatiales), IPSL/CNRS/UVSQ, 11 Bd d’Alembert, Guyancourt, 78280 France
| | - Yu Lin
- Auburn University, Auburn, USA
| | - Terry Liu
- Physics Department & Geophysical Institute, University of Alaska Fairbanks, 2156 Koyukuk Drive, Fairbanks, AK 99775 USA
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, Los Angeles, USA
| | - Kjellmar Oksavik
- Birkeland Centre for Space Science, Department of Physics and Technology, University of Bergen, Bergen, Norway
- Arctic Geophysics, The University Centre in Svalbard, Longyearbyen, Norway
| | | | - Antonius Otto
- Physics Department & Geophysical Institute, University of Alaska Fairbanks, 2156 Koyukuk Drive, Fairbanks, AK 99775 USA
| | - Jie Ren
- Institute of Space Physics and Applied Technology, Peking University, Beijing, 100871 China
| | | | - David Sibeck
- NASA Goddard Space Flight Center, Greenbelt, MD 20771 USA
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Downstream high-speed plasma jet generation as a direct consequence of shock reformation. Nat Commun 2022; 13:598. [PMID: 35105885 PMCID: PMC8807623 DOI: 10.1038/s41467-022-28110-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 01/07/2022] [Indexed: 11/16/2022] Open
Abstract
Shocks are one of nature’s most powerful particle accelerators and have been connected to relativistic electron acceleration and cosmic rays. Upstream shock observations include wave generation, wave-particle interactions and magnetic compressive structures, while at the shock and downstream, particle acceleration, magnetic reconnection and plasma jets can be observed. Here, using Magnetospheric Multiscale (MMS) we show in-situ evidence of high-speed downstream flows (jets) generated at the Earth’s bow shock as a direct consequence of shock reformation. Jets are observed downstream due to a combined effect of upstream plasma wave evolution and an ongoing reformation cycle of the bow shock. This generation process can also be applicable to planetary and astrophysical plasmas where collisionless shocks are commonly found. Several mechanisms exist for formation of jets observed in Earth’s magnetosheath. Here, the authors show evidence of high-speed downstream flows generated at the Earth’s bow shock as a direct consequence of shock reformation, which is different than the proposed mechanisms.
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Plaschke F, Hietala H, Angelopoulos V, Nakamura R. Geoeffective jets impacting the magnetopause are very common. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2016; 121:3240-3253. [PMID: 27478719 PMCID: PMC4950216 DOI: 10.1002/2016ja022534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 03/22/2016] [Accepted: 03/25/2016] [Indexed: 06/06/2023]
Abstract
The subsolar magnetosheath is penetrated by transient enhancements in dynamic pressure. These enhancements, also called high-speed jets, can propagate to the magnetopause, causing large-amplitude yet localized boundary indentations on impact. Possible downstream consequences of these impacts are, e.g., local magnetopause reconnection, impulsive penetration of magnetosheath plasma into the magnetosphere, inner magnetospheric and boundary surface waves, drop outs and other variations in radiation belt electron populations, ionospheric flow enhancements, and magnetic field variations observed on the ground. Consequently, jets can be geoeffective. The extend of their geoeffectiveness is influenced by the amount of mass, momentum, and energy they transport, i.e., by how large they are. Their overall importance in the framework of solar wind-magnetosphere coupling is determined by how often jets of geoeffective size hit the dayside magnetopause. In this paper, we calculate such jet impact rates for the first time. From a large data set of Time History of Events and Macroscale Interactions during Substorms (THEMIS) multispacecraft jet observations, we find distributions of scale sizes perpendicular and parallel to the direction of jet propagation. They are well modeled by an exponential function with characteristic scales of 1.34RE (perpendicular) and 0.71RE (parallel direction), respectively. Using the distribution of perpendicular scale sizes, we derive an impact rate of jets with cross-sectional diameters larger than 2RE on a reference area of about 100RE2 of the subsolar magnetopause. That rate is about 3 per hour in general, and about 9 per hour under low interplanetary magnetic field cone angle conditions (<30°), which are favorable for jet occurrence in the subsolar magnetosheath.
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Affiliation(s)
- F. Plaschke
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - H. Hietala
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - V. Angelopoulos
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
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Hietala H, Plaschke F. On the generation of magnetosheath high-speed jets by bow shock ripples. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2013; 118:7237-7245. [PMID: 26167426 PMCID: PMC4497490 DOI: 10.1002/2013ja019172] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 09/05/2013] [Accepted: 11/02/2013] [Indexed: 06/04/2023]
Abstract
[1]The terrestrial magnetosheath is embedded with coherent high-speed jets of about 1RE in scale, predominantly during quasi-radial interplanetary magnetic field (IMF). When these high dynamic pressure (Pdyn) jets hit the magnetopause, they cause large indentations and further magnetospheric effects. The source of these jets has remained controversial. One of the proposed mechanisms is based on ripples of the quasi-parallel bow shock. In this paper, we combine for the first time, 4 years of subsolar magnetosheath observations from the Time History of Events and Macroscale Interactions during Substorms mission and corresponding NASA/OMNI solar wind conditions with model calculations of a rippled bow shock. Concentrating on the magnetosheath close to the shock during intervals when the angle between the IMF and the Sun-Earth line was small, we find that (1) 97% of the observed jets can be produced by local ripples of the shock under the observed upstream conditions; (2) the coherent jets form a significant fraction of the high Pdyn tail of the magnetosheath flow distribution; (3) the magnetosheath Pdyn distribution matches the flow from a bow shock with ripples that have a dominant amplitude to wavelength ratio of about 9% (∼0.1RE/1RE) and are present ∼12% of the time at any given location.
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Affiliation(s)
- H Hietala
- Blackett Laboratory, Imperial College London London, UK
| | - F Plaschke
- Space Research Institute, Austrian Academy of Sciences Graz, Austria
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