DOCSLIB.ORG

Current Sheets, Magnetic Islands, and Associated Particle Acceleration in the Solar Wind As Observed by Ulysses Near the Ecliptic Plane

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Current Sheets, Magnetic Islands, and Associated Particle Acceleration in the Solar Wind As Observed by Ulysses Near the Ecliptic Plane The Astrophysical Journal, 881:116 (20pp), 2019 August 20 https://doi.org/10.3847/1538-4357/ab289a © 2019. The American Astronomical Society. All rights reserved. Current Sheets, Magnetic Islands, and Associated Particle Acceleration in the Solar Wind as Observed by Ulysses near the Ecliptic Plane Olga Malandraki1 , Olga Khabarova2,17 , Roberto Bruno3 , Gary P. Zank4 , Gang Li4 , Bernard Jackson5 , Mario M. Bisi6 , Antonella Greco7 , Oreste Pezzi8,9,10 , William Matthaeus11 , Alexandros Chasapis Giannakopoulos11 , Sergio Servidio7, Helmi Malova12,13 , Roman Kislov2,13 , Frederic Effenberger14,15 , Jakobus le Roux4 , Yu Chen4 , Qiang Hu4 , and N. Eugene Engelbrecht16 1 IAASARS, National Observatory of Athens, Penteli, Greece 2 Heliophysical Laboratory, Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation of the Russian Academy of Sciences (IZMIRAN), Moscow, Russia; [email protected] 3 Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica (IAPS-INAF), Roma, Italy 4 Center for Space Plasma and Aeronomic Research (CSPAR) and Department of Space Science, University of Alabama in Huntsville, Huntsville, AL 35805, USA 5 University of California, San Diego, CASS/UCSD, La Jolla, CA, USA 6 RAL Space, United Kingdom Research and Innovation—Science & Technology Facilities Council—Rutherford Appleton Laboratory, Harwell Campus, Oxfordshire, OX11 0QX, UK 7 Physics Department, University of Calabria, Italy 8 Gran Sasso Science Institute, Viale F. Crispi 7, I-67100 L’Aquila, Italy 9 INFN/Laboratori Nazionali del Gran Sasso, Via G. Acitelli 22, I-67100 Assergi (AQ), Italy 10 Dipartimento di Fisica, Universita’ della Calabria, I-87036 Cosenza, Italy 11 Department of Physics and Astronomy, University of Delaware, Newark, DE 19716, USA 12 Scobeltsyn Nuclear Physics Institute of Lomonosov Moscow State University, Moscow, Russia 13 Space Research Institute (IKI) RAS, Moscow, Russia 14 Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Potsdam, Germany 15 Bay Area Environmental Research Institute, NASA Research Park, Moffett Field, CA 94035, USA 16 Center for Space Research, North-West University of Potchefstroom, South Africa Received 2018 August 28; revised 2019 May 23; accepted 2019 June 7; published 2019 August 20 Abstract Recent studies of particle acceleration in the heliosphere have revealed a new mechanism that can locally energize particles up to several MeV nucleon–1. Stream–stream interactions, as well as the heliospheric current sheet (CS)— stream interactions, lead to formation of large magnetic cavities, bordered by strong CSs, which in turn produce secondary CSs and dynamical small-scale magnetic islands (SMIs) of ∼0.01 au or less owing to magnetic reconnection. It has been shown that particle acceleration or reacceleration occurs via stochastic magnetic reconnection in dynamical SMIs confined inside magnetic cavities observed at 1 au. The study links the occurrence of CSs and SMIs with characteristics of intermittent turbulence and observations of energetic particles of keV– MeV nucleon–1 energies at ∼5.3 au. We analyze selected samples of different plasmas observed by Ulysses during a widely discussed event, which was characterized by a series of high-speed streams of various origins that interacted beyond Earth’s orbit in 2005 January. The interactions formed complex conglomerates of merged interplanetary coronal mass ejections, stream/corotating interaction regions, and magnetic cavities. We study properties of turbulence and associated structures of various scales. We confirm the importance of intermittent turbulence and magnetic reconnection in modulating solar energetic particle flux and even local particle acceleration. Coherent structures, including CSs and SMIs, play a significant role in the development of secondary stochastic particle acceleration, which changes the observed energetic particle flux time–intensity profiles and increases the final energy level to which energetic particles can be accelerated in the solar wind. Key words: acceleration of particles – magnetic reconnection – solar wind – Sun: heliosphere – Sun: magnetic fields – turbulence Supporting material: animation 1. Introduction heliosphere are known to be accelerated during solar flares and at coronal mass ejection (CME) driven shocks. In the latter Energetic particles in the heliosphere and magnetosphere case, the acceleration process is most effective in the corona. pose significant radiation hazards for astronauts in current and Generated energetic particles are referred to as solar energetic future space missions in our solar system (e.g., to Mars) and for particles (SEPs; Reames 1999; Malandraki et al. 2012; Desai & communication satellites (e.g., Iucci et al. 2006; National Giacalone 2016; Malandraki & Crosby 2018a, 2018b). Another Research Council 2006; Malandraki 2015; Miroshnichenko – –1 / ) source of keV MeV nucleon energetic particles is stream 2015; Malandraki & Crosby 2018a, 2018b . Studies of their corotating interaction regions (SIR/sCIRs). In this case, origin and properties are very important for timely protection of acceleration takes place at SIR/CIR-driven shocks usually onboard equipment and human resources. Protons and formed at 2–3au(Malandraki et al. 2007; Tsubouchi 2014; – electrons of keV MeV energies observed in the inner Richardson 2018). In summary, the dominant paradigm suggests that energetic particles in the keV–MeV energy range 17 Author for correspondence. propagate to 1 au either from the Sun or from distant sources 1 The Astrophysical Journal, 881:116 (20pp), 2019 August 20 Malandraki et al. associated with CIRs, and thus the effect of local processes can accordance with expectations of SEP observations at 1 au, but be neglected. keV–MeV energy ion flux shows variations, increases, and The standard mechanism typically invoked to explain the time delays corresponding to propagation of some solar wind energization of particles locally in the solar wind is that of structures (see Khabarova et al. 2015a and references therein). diffusive shock acceleration (DSA), as shown by Lee & Ryan The role of DSA in local particle acceleration has been found (1986) and Zank et al. (2000), although other mechanisms have not to be of primary importance in many events. Khabarova & been proposed (e.g., Fisk & Gloeckler 2012, 2014; Laurenza Zank (2017) illustrated how to distinguish between effects of et al. 2016; Pallocchia et al. 2017). The basic physics were local DSA and particle energization associated with another elucidated especially well in the seminal papers of Axford local source, which can be more effective, just through the et al. (1982) and Bell (1978a, 1978b) in the context of the visual inspection of time–intensity profiles of the energetic astrophysical problem of cosmic-ray acceleration at supernova particle flux in different energy channels (e.g., see their remnants. However, detailed interplanetary observations are Figure 12). Khabarova & Zank (2017) carried out an extensive not easily interpreted in terms of the simple original steady- analysis of particle energization in the vicinity of reconnecting state models of particle acceleration at shock waves. Three exhausts observed in the supersonic solar wind by the ACE fundamental aspects make the interplanetary problem more spacecraft. Both the case study analysis and the superposed complicated than the typical astrophysical problem: the time epoch analysis of 126 reconnection exhaust events, which dependence of the acceleration and the solar wind background, mainly occurred within interplanetary coronal mass ejections the geometry of the shock, and the long mean free path for (ICMEs), showed that energetic ions are accelerated up to at particle transport away from the shock. Consequently, the least 5 MeV and electrons up to 0.315 MeV within a time shock itself introduces a multiplicity of timescales, ranging interval of ±30 hr around reconnecting current sheets (CSs). from shock propagation timescales to particle acceleration Khabarova & Zank (2017) concluded that the observed long- timescales at parallel and perpendicular shocks. Many of these timescale atypical energetic particle event (AEPE) encompass- — timescales feed into other timescales these can determine ing the reconnection exhausts is very likely related to secondary maximum particle energy scalings or escape timescales, for reacceleration of energetic particles in SMIs or medium-scale example, from which accelerated particle distribution functions magnetic islands surrounding the reconnecting CSs. Their are predicted that can be broken power laws or power laws with results are in a very good agreement with predictions based on exponential rollovers in velocity space. a theory of stochastic particle energization in the supersonic Models describing the acceleration of ions at CME-driven solar wind via numerous dynamically interacting small-scale shocks have become increasingly sophisticated and capable flux ropes (Zank et al. 2014, 2015a, 2015b; le Roux et al. of explaining many observations associated with gradual 2015, 2016, 2018a, 2018b). Initial particle acceleration may events (Zank et al. 2000; Rice et al. 2003; Li et al. 2003; occur in different ways, including acceleration at interplanetary Verkhoglyadova et al. 2015). Only relatively low-energy shocks combined with reconnection at CSs. energetic particles tend to remain localized near the shock Reconnecting small-scale CSs are observed very often where DSA occurs. These spectra,
Load more

Recommended publications
  • Fundamentals of Impulsive Energy Release in the Corona Heliophysics 2050 Workshop White Paper A
    Heliophysics 2050 White Papers (2021) 4093.pdf Fundamentals of impulsive energy release in the corona Heliophysics 2050 Workshop white paper A. Y. Shih (NASA Goddard Space Flight Center), L. Glesener (UMN), S. Krucker (UCB), S. Guidoni (Amer. Univ.), S. Christe (GSFC), K. Reeves (SAO), S. Gburek (PAS), A. Caspi (SwRI), M. Alaoui (GSFC/CUA), J. Allred (GSFC), M. Battaglia (FHNW), W. Baumgartner (MSFC), B. Dennis (GSFC), J. Drake (UMD), K. Goetz (UMN), L. Golub (SAO), I. Hannah (Univ. of Glasgow), L. Hayes (GSFC/USRA), G. Holman (GSFC/Emeritus), A. Inglis (GSFC/CUA), J. Ireland (GSFC), G. Kerr (GSFC/CUA), J. Klimchuk (GSFC), D. McKenzie (MSFC), C. Moore (SAO), S. Musset (Univ. of Glasgow), J. Reep (NRL), D. Ryan (GSFC/AU), P. Saint-Hilaire (UCB), S. Savage (MSFC), R. Schwartz (GSFC/AU), D. Seaton (NOAA), M. Stęślicki (PAS), T. Woods (LASP) Introduction Solar eruptive events are the most energetic and geo-effective space-weather drivers. They originate in the corona near the Sun’s surface as a combination of solar flares (impulsive bursts of radiation across the entire electromagnetic spectrum) and coronal mass ejections (CMEs; expulsions of magnetized plasma into interplanetary space). The radiation and energetic particles they produce can damage satellites, disrupt telecommunications and GPS navigation, and endanger astronauts in space. Many of the processes involved in triggering, driving, and sustaining solar eruptive events–including magnetic reconnection, particle acceleration, plasma heating, and energy transport in magnetized plasmas–also play important roles in phenomena throughout the Universe, such as in magnetospheric substorms, gamma-ray bursts, and accretion disks. The Sun is a unique laboratory to better understand these fundamental physical processes.
    [Show full text]
  • Observations of Solar Wind Penetration Into the Earth's Magnetosphere: the Plasma Mantle
    ENNIO R. SANCHEZ, CHING-I. MENG, and PATRICK T. NEWELL OBSERVATIONS OF SOLAR WIND PENETRATION INTO THE EARTH'S MAGNETOSPHERE: THE PLASMA MANTLE The large database provided by the continuous coverage of the Defense Meteorological Satellite Pro­ gram polar orbiting satellites constitutes an important source of information on particle precipitation in the ionosphere. This information can be used to monitor and map the Earth's magnetosphere (the cavity around the Earth that forms as the stream of particles and magnetic field ejected from the Sun, known as the solar wind, encounters the Earth's magnetic field) and for a large variety of statistical studies of its morphology and dynamics. The boundary between the magnetosphere and the solar wind is pre­ sumably open in some places and at some times, thus allowing the direct entry of solar-wind plasma into the magnetosphere through a boundary layer known as the plasma mantle. The preliminary results of a statistical study of the plasma-mantle precipitation in the ionosphere are presented. The first quan­ titative mapping of the ionospheric region where the plasma-mantle particles precipitate is obtained. INTRODUCTION Polar orbiting satellites are very useful platforms for studying the properties of the environment surrounding the Earth at distances well above the ionosphere. This article focuses on a description of the enormous poten­ tial of those platforms, especially when they are com­ bined with other means of measurement, such as ground-based stations and other satellites. We describe in some detail the first results of the kind of study for which the polar orbiting satellites are ideal instruments.
    [Show full text]
  • Solar and Space Physics: a Science for a Technological Society
    Solar and Space Physics: A Science for a Technological Society The 2013-2022 Decadal Survey in Solar and Space Physics Space Studies Board ∙ Division on Engineering & Physical Sciences ∙ August 2012 From the interior of the Sun, to the upper atmosphere and near-space environment of Earth, and outwards to a region far beyond Pluto where the Sun’s influence wanes, advances during the past decade in space physics and solar physics have yielded spectacular insights into the phenomena that affect our home in space. This report, the final product of a study requested by NASA and the National Science Foundation, presents a prioritized program of basic and applied research for 2013-2022 that will advance scientific understanding of the Sun, Sun- Earth connections and the origins of “space weather,” and the Sun’s interactions with other bodies in the solar system. The report includes recommendations directed for action by the study sponsors and by other federal agencies—especially NOAA, which is responsible for the day-to-day (“operational”) forecast of space weather. Recent Progress: Significant Advances significant progress in understanding the origin from the Past Decade and evolution of the solar wind; striking advances The disciplines of solar and space physics have made in understanding of both explosive solar flares remarkable advances over the last decade—many and the coronal mass ejections that drive space of which have come from the implementation weather; new imaging methods that permit direct of the program recommended in 2003 Solar observations of the space weather-driven changes and Space Physics Decadal Survey. For example, in the particles and magnetic fields surrounding enabled by advances in scientific understanding Earth; new understanding of the ways that space as well as fruitful interagency partnerships, the storms are fueled by oxygen originating from capabilities of models that predict space weather Earth’s own atmosphere; and the surprising impacts on Earth have made rapid gains over discovery that conditions in near-Earth space the past decade.
    [Show full text]
  • THEMIS Telescope Images Analysed for Space Weather Traces
    EPSC Abstracts Vol. 14, EPSC2020-1022, 2020 https://doi.org/10.5194/epsc2020-1022 Europlanet Science Congress 2020 © Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. THEMIS telescope images analysed for space weather traces Melinda Dósa1, Valeria Mangano2, Zsofia Bebesi1, Stefano Massetti2, Anna Milillo2, and Anna Görgei3 1Wigner Research Centre for Physics, Space Physics and Space Technology, Budapest, Hungary ([email protected]) 2INAF/IAPS, Istituto Nazionale di Astrofisica, Roma, Italy 3Eötvös Loránd University, Institute of Physics The THEMIS solar telescope operating on Tenerife (Canary islands) has observed Mercury’s Na exosphere along several campaigns since 2007. A dataset of images taken between 2009 and 2013 are analysed here in relation with propagated solar wind data. A small subset of the images shows a low level of correlation between Na-emission and solar wind dynamic pressure. The amount of data at present is not sufficient to make a clear statement on whether the correlation is a coincidence or can be explained by other factors (position of Mercury and Earth, solar activity, etc.). Nevertheless, the authors present a comprehensive study taking into account all possible factors. Sodium plays a special role in Mercury’s exosphere: due to its strong resonance line it has been observed and monitored by Earth-based telescopes for decades. Different and highly variable patterns of Na-emission have been identified, the most common and recurrent being the high latitude double-peak pattern [1]. It is clear that the exosphere is linked to the surface and influenced by the interstellar medium and the solar wind deviated by the magnetosphere, but the role and weight of the single processes are still under discussion [2].
    [Show full text]
  • Cmes, Solar Wind and Sun-Earth Connections: Unresolved Issues
    CMEs, solar wind and Sun-Earth connections: unresolved issues Rainer Schwenn Max-Planck-Institut für Sonnensystemforschung, Katlenburg-Lindau, Germany [email protected] In recent years, an unprecedented amount of high-quality data from various spaceprobes (Yohkoh, WIND, SOHO, ACE, TRACE, Ulysses) has been piled up that exhibit the enormous variety of CME properties and their effects on the whole heliosphere. Journals and books abound with new findings on this most exciting subject. However, major problems could still not be solved. In this Reporter Talk I will try to describe these unresolved issues in context with our present knowledge. My very personal Catalog of ignorance, Updated version (see SW8) IAGA Scientific Assembly in Toulouse, 18-29 July 2005 MPRS seminar on January 18, 2006 The definition of a CME "We define a coronal mass ejection (CME) to be an observable change in coronal structure that occurs on a time scale of a few minutes and several hours and involves the appearance (and outward motion, RS) of a new, discrete, bright, white-light feature in the coronagraph field of view." (Hundhausen et al., 1984, similar to the definition of "mass ejection events" by Munro et al., 1979). CME: coronal -------- mass ejection, not: coronal mass -------- ejection! In particular, a CME is NOT an Ejección de Masa Coronal (EMC), Ejectie de Maså Coronalå, Eiezione di Massa Coronale Éjection de Masse Coronale The community has chosen to keep the name “CME”, although the more precise term “solar mass ejection” appears to be more appropriate. An ICME is the interplanetry counterpart of a CME 1 1.
    [Show full text]
  • Solar Wind Magnetosphere Coupling
    Solar Wind Magnetosphere Coupling F. Toffoletto, Rice University Figure courtesy T. W. Hill with thanks to R. A. Wolf and T. W. Hill, Rice U. Outline • Introduction • Properties of the Solar Wind Near Earth • The Magnetosheath • The Magnetopause • Basic Physical Processes that control Solar Wind Magnetosphere Coupling – Open and Closed Magnetosphere Processes – Electrodynamic coupling – Mass, Momentum and Energy coupling – The role of the ionosphere • Current Status and Summary QuickTime™ and a YUV420 codec decompressor are needed to see this picture. Introduction • By virtue of our proximity, the Earth’s magnetosphere is the most studied and perhaps best understood magnetosphere – The system is rather complex in its structure and behavior and there are still some basic unresolved questions – Today’s lecture will focus on describing the coupling to the major driver of the magnetosphere - the solar wind, and the ionosphere – Monday’s lecture will look more at the more dynamic (and controversial) aspect of magnetospheric dynamics: storms and substorms The Solar Wind Near the Earth Solar-Wind Properties Observed Near Earth • Solar wind parameters observed by many spacecraft over period 1963-86. From Hapgood et al. (Planet. Space Sci., 39, 410, 1991). Solar Wind Observed Near Earth Values of Solar-Wind Parameters Parameter Minimum Most Maximum Probable Velocity v (km/s) 250 370 2000× Number density n (cm-3) 683 Ram pressure rv2 (nPa)* 328 Magnetic field strength B 0 6 85 (nanoteslas) IMF Bz (nanoteslas) -31 0¤ 27 * 1 nPa = 1 nanoPascal = 10-9 Newtons/m2. Indicates at least one interval with B < 0.1 nT. ¤ Mean value was 0.014 nT, with a standard deviation of 3.3 nT.
    [Show full text]
  • THEMIS Observations of a Hot Flow Anomaly: Solar Wind, Magnetosheath, and Ground-Based Measurements J
    THEMIS observations of a hot flow anomaly: Solar wind, magnetosheath, and ground-based measurements J. Eastwood, D. Sibeck, V. Angelopoulos, T. Phan, S. Bale, J. Mcfadden, C. Cully, S. Mende, D. Larson, S. Frey, et al. To cite this version: J. Eastwood, D. Sibeck, V. Angelopoulos, T. Phan, S. Bale, et al.. THEMIS observations of a hot flow anomaly: Solar wind, magnetosheath, and ground-based measurements. Geophysical Research Letters, American Geophysical Union, 2008, 35 (17), pp.L17S03. 10.1029/2008GL033475. hal- 03086705 HAL Id: hal-03086705 https://hal.archives-ouvertes.fr/hal-03086705 Submitted on 23 Dec 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. GEOPHYSICAL RESEARCH LETTERS, VOL. 35, L17S03, doi:10.1029/2008GL033475, 2008 THEMIS observations of a hot flow anomaly: Solar wind, magnetosheath, and ground-based measurements J. P. Eastwood,1 D. G. Sibeck,2 V. Angelopoulos,3 T. D. Phan,1 S. D. Bale,1,4 J. P. McFadden,1 C. M. Cully,5,6 S. B. Mende,1 D. Larson,1 S. Frey,1 C. W. Carlson,1 K.-H. Glassmeier,7 H. U. Auster,7 A. Roux,8 and O.
    [Show full text]
  • Heliophysics Division Space Weather Strategy HPAC, June 30 – July 1, 2020
    Heliophysics Division Space Weather Strategy HPAC, June 30 – July 1, 2020 1 Heliophysics Space Weather Strategy This strategy outlines the goals and objectives of NASA Heliophysics Division with respect to space weather. It is consistent with the goals and agency responsibilities articulated in the 2019 National Space Weather Strategy and Action Plan, as well as the Agency’s efforts in human and robotic exploration. Context • Understanding space weather is the domain of Heliophysics. Space weather is the applied expression of Heliophysics. In Priority 1 of the 2020 NASA Science Plan, Strategy 1.4 pertains directly to space weather: Develop a Directorate-wide, target-user focused approach to applied programs, including Earth Science Applications, Space Weather, Planetary Defense, and ⁻ Space Situational Awareness. 2 Space Weather Strategy Vision • Advance the science of space weather to empower a technological society safely thriving on Earth and expanding into space. Mission • Establish a preeminent space weather capability that supports robotic and human space exploration and meets national, international, and societal needs by advancing measurement and analysis techniques, and by expanding knowledge and understanding for transitioning into improved operational space weather forecasts and nowcasts. 3 1. Observe • Advance observation techniques, technology, Goals and capability 2. Analyze • NASA plays a vital role in space • Advance research, analysis and modeling weather research by providing capability unique, significant, and exploratory 3. Predict observations and data streams for • Improve space weather forecast and nowcast theory, modeling, and data analysis capabilities research, and for operations. 4. Transition • NASA’s contributions to observing • Transition capabilities to operational and understanding space weather environments are critical for the success of the National and International space 5.
    [Show full text]
  • A Decadal Strategy for Solar and Space Physics
    Space Weather and the Next Solar and Space Physics Decadal Survey Daniel N. Baker, CU-Boulder NRC Staff: Arthur Charo, Study Director Abigail Sheffer, Associate Program Officer Decadal Survey Purpose & OSTP* Recommended Approach “Decadal Survey benefits: • Community-based documents offering consensus of science opportunities to retain US scientific leadership • Provides well-respected source for priorities & scientific motivations to agencies, OMB, OSTP, & Congress” “Most useful approach: • Frame discussion identifying key science questions – Focus on what to do, not what to build – Discuss science breadth & depth (e.g., impact on understanding fundamentals, related fields & interdisciplinary research) • Explain measurements & capabilities to answer questions • Discuss complementarity of initiatives, relative phasing, domestic & international context” *From “The Role of NRC Decadal Surveys in Prioritizing Federal Funding for Science & Technology,” Jon Morse, Office of Science & Technology Policy (OSTP), NRC Workshop on Decadal Surveys, November 14-16, 2006 2 Context The Sun to the Earth—and Beyond: A Decadal Research Strategy in Solar and Space Physics Summary Report (2002) Compendium of 5 Study Panel Reports (2003) First NRC Decadal Survey in Solar and Space Physics Community-led Integrated plan for the field Prioritized recommendations Sponsors: NASA, NSF, NOAA, DoD (AFOSR and ONR) 3 Decadal Survey Purpose & OSTP* Recommended Approach “Decadal Survey benefits: • Community-based documents offering consensus of science opportunities
    [Show full text]
  • Solar Wind Properties and Geospace Impact of Coronal Mass Ejection-Driven Sheath Regions: Variation and Driver Dependence E
    Solar Wind Properties and Geospace Impact of Coronal Mass Ejection-Driven Sheath Regions: Variation and Driver Dependence E. K. J. Kilpua, D. Fontaine, C. Moissard, M. Ala-lahti, E. Palmerio, E. Yordanova, S. Good, M. M. H. Kalliokoski, E. Lumme, A. Osmane, et al. To cite this version: E. K. J. Kilpua, D. Fontaine, C. Moissard, M. Ala-lahti, E. Palmerio, et al.. Solar Wind Properties and Geospace Impact of Coronal Mass Ejection-Driven Sheath Regions: Variation and Driver Dependence. Space Weather: The International Journal of Research and Applications, American Geophysical Union (AGU), 2019, 17 (8), pp.1257-1280. 10.1029/2019SW002217. hal-03087107 HAL Id: hal-03087107 https://hal.archives-ouvertes.fr/hal-03087107 Submitted on 23 Dec 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. RESEARCH ARTICLE Solar Wind Properties and Geospace Impact of Coronal 10.1029/2019SW002217 Mass Ejection-Driven Sheath Regions: Variation and Key Points: Driver Dependence • Variation of interplanetary properties and geoeffectiveness of CME-driven sheaths and their dependence on the E. K. J. Kilpua1 , D. Fontaine2 , C. Moissard2 , M. Ala-Lahti1 , E. Palmerio1 , ejecta properties are determined E.
    [Show full text]
  • Atmospheric Escape from the TRAPPIST-1 Planets\Xmlpi{\\}
    Atmospheric escape from the TRAPPIST-1 planets and implications for habitability Chuanfei Donga,b,1, Meng Jinc, Manasvi Lingamd,e, Vladimir S. Airapetianf, Yingjuan Mag, and Bart van der Holsth aDepartment of Astrophysical Sciences, Princeton University, Princeton, NJ 08544; bPrinceton Center for Heliophysics, Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08544; cLockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94304; dInstitute for Theory and Computation, Harvard–Smithsonian Center for Astrophysics, Cambridge, MA 02138; eJohn A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138; fHeliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771; gInstitute of Geophysics and Planetary Physics, University of California, Los Angeles, CA 90095; and hCenter for Space Environment Modeling, University of Michigan, Ann Arbor, MI 48109 Edited by Neta A. Bahcall, Princeton University, Princeton, NJ, and approved December 4, 2017 (received for review May 15, 2017) The presence of an atmosphere over sufficiently long timescales dence from our own Solar System suggests that the erosion of the is widely perceived as one of the most prominent criteria asso- atmosphere by the stellar wind plays a crucial role, especially for ciated with planetary surface habitability. We address the crucial Earth-sized planets where such losses constitute the dominant question of whether the seven Earth-sized planets transiting the mechanism (13, 14), and the same could also be true for exo- recently discovered ultracool dwarf star TRAPPIST-1 are capable of planets around M dwarfs (15, 16). Recent studies of atmospheric retaining their atmospheres. To this effect, we carry out numerical ion escape rates from Proxima b (and other M-dwarf exoplanets) simulations to characterize the stellar wind of TRAPPIST-1 and the also appear to indicate that the resulting ion losses are signifi- atmospheric ion escape rates for all of the seven planets.
    [Show full text]
  • Interplanetary Conditions Causing Intense Geomagnetic Storms (Dst 100 Nt) During Solar Cycle 23 (1996–2006) E
    JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 113, A05221, doi:10.1029/2007JA012744, 2008 Interplanetary conditions causing intense geomagnetic storms (Dst ÀÀÀ100 nT) during solar cycle 23 (1996–2006) E. Echer,1 W. D. Gonzalez,1 B. T. Tsurutani,2 and A. L. C. Gonzalez1 Received 21 August 2007; revised 24 January 2008; accepted 8 February 2008; published 30 May 2008. [1] The interplanetary causes of intense geomagnetic storms and their solar dependence occurring during solar cycle 23 (1996–2006) are identified. During this solar cycle, all intense (Dst À100 nT) geomagnetic storms are found to occur when the interplanetary magnetic field was southwardly directed (in GSM coordinates) for long durations of time. This implies that the most likely cause of the geomagnetic storms was magnetic reconnection between the southward IMF and magnetopause fields. Out of 90 storm events, none of them occurred during purely northward IMF, purely intense IMF By fields or during purely high speed streams. We have found that the most important interplanetary structures leading to intense southward Bz (and intense magnetic storms) are magnetic clouds which drove fast shocks (sMC) causing 24% of the storms, sheath fields (Sh) also causing 24% of the storms, combined sheath and MC fields (Sh+MC) causing 16% of the storms, and corotating interaction regions (CIRs), causing 13% of the storms. These four interplanetary structures are responsible for three quarters of the intense magnetic storms studied. The other interplanetary structures causing geomagnetic storms were: magnetic clouds that did not drive a shock (nsMC), non magnetic clouds ICMEs, complex structures resulting from the interaction of ICMEs, and structures resulting from the interaction of shocks, heliospheric current sheets and high speed stream Alfve´n waves.
    [Show full text]