Cumulative instabilities of anisotropic protons and electrons in the solar wind: New insights from a quasilinear approach

Mapping Intimacies ◽

10.5194/egusphere-egu21-7565 ◽

2021 ◽

Author(s):

Shaaban Mohammed Shaaban Hamd ◽

Marian Lazar ◽

Rodrigo R. López ◽

Robert F. Wimmer-Schweingruber ◽

Horst Fichtner

Keyword(s):

Solar Wind ◽

Cumulative Effects ◽

Space Plasmas ◽

Physical Processes ◽

Temporal Scales ◽

First Results ◽

Kinetic Instabilities

<p>In collision-poor space plasmas the main physical processes are governed by fluctuations and their interactions with plasma particles. An important <span>source of waves and coherent fluctuations are kinetic instabilities driven </span>by, e.g., protons and electrons exhibiting temperature anisotropies. Unfortunately, such instabilities are generally investigated independently of each other, thereby ignoring their interplay and preventing a realistic treatment of their implications. Here we present the first results of an extended quasilinear approach, which not only confirms linear predictions but also unveils new regimes triggered by cumulative effects of the proton <span>and electron instabilities (e.g., electromagnetic cyclotron, firehose). By </span>comparison to individual excitations combined proton- and electron-induced fluctuations grow and saturate at different intensities as well as different temporal scales in the quasilinear phase. Moreover, the enhanced wave fluctuations can markedly stimulate or inhibit the relaxation of temperature anisotropies, this way highly conditioning the evolution and saturation of instabilities.</p>

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Solar wind temperature anisotropy constraints from streaming instabilities

Astronomy and Astrophysics ◽

10.1051/0004-6361/201731852 ◽

2018 ◽

Vol 613 ◽

pp. A23 ◽

Cited By ~ 3

Author(s):

S. Vafin ◽

M. Lazar ◽

H. Fichtner ◽

R. Schlickeiser ◽

M. Drillisch

Keyword(s):

Solar Wind ◽

Large Deviations ◽

The Other ◽

Space Plasmas ◽

Plasma Stability ◽

Particle Collisions ◽

Temperature Anisotropy ◽

Large Interval ◽

Low Rate ◽

Kinetic Instabilities

Due to the relatively low rate of particle-particle collisions in the solar wind, kinetic instabilities (e.g., the mirror and firehose) play an important role in regulating large deviations from temperature isotropy. These instabilities operate in the high β∥ > 1 plasmas, and cannot explain the other limits of the temperature anisotropy reported by observations in the low beta β∥ < 1 regimes. However, the instability conditions are drastically modified in the presence of streaming (or counterstreaming) components, which are ubiquitous in space plasmas. These effects have been analyzed for the solar wind conditions in a large interval of heliospheric distances, 0.3–2.5 AU. It was found that proton counter-streams are much more crucial for plasma stability than electron ones. Moreover, new instability thresholds can potentially explain all observed bounds on the temperature anisotropy, and also the level of differential streaming in the solar wind.

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Lunar Plasma Environment in Cases with Extreme Solar Wind Conditions: First Results from3-D Hybrid Kinetic Modeling and Comparison with ARTEMIS Observations

10.1002/essoar.10505143.1 ◽

2020 ◽

Author(s):

Alexander Lipatov ◽

Menelaos Sarantos ◽

John Cooper ◽

Jasper Halekas

Keyword(s):

Solar Wind ◽

Kinetic Modeling ◽

Plasma Environment ◽

First Results

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HelioSwarm: The Nature of Turbulence in Space Plasmas

10.5194/egusphere-egu21-12092 ◽

2021 ◽

Author(s):

Harlan Spence ◽

Kristopher Klein ◽

HelioSwarm Science Team

Keyword(s):

Magnetic Field ◽

Solar Wind ◽

Large Scale ◽

Solar Wind Plasma ◽

Turbulent Energy ◽

Space Plasmas ◽

Plasma Parameters ◽

Astrophysical Plasmas ◽

Ion Distributions ◽

Background Magnetic Field

<p>Recently selected for phase A study for NASA&#8217;s Heliophysics MidEx Announcement of Opportunity, the HelioSwarm Observatory proposes to transform our understanding of the physics of turbulence in space and astrophysical plasmas by deploying nine spacecraft to measure the local plasma and magnetic field conditions at many points, with separations between the spacecraft spanning MHD and ion scales.&#160;&#160;HelioSwarm resolves the transfer and dissipation of turbulent energy in weakly-collisional magnetized plasmas with a novel configuration of spacecraft in the solar wind. These simultaneous multi-point, multi-scale measurements of space plasmas allow us to reach closure on two science goals comprised of six science objectives: (1) reveal how turbulent energy is transferred in the most probable, undisturbed solar wind plasma and distributed as a function of scale and time; (2) reveal how this turbulent cascade of energy varies with the background magnetic field and plasma parameters in more extreme solar wind environments; (3) quantify the transfer of turbulent energy between fields, flows, and ion heat; (4) identify thermodynamic impacts of intermittent structures on ion distributions; (5) determine how solar wind turbulence affects and is affected by large-scale solar wind structures; and (6) determine how strongly driven turbulence differs from that in the undisturbed solar wind.&#160;</p>

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Evolution of the MHD turbulence properties in the inner heliosphere with the PSP/SolO alignment data

10.5194/egusphere-egu21-14585 ◽

2021 ◽

Author(s):

Daniele Telloni ◽

Keyword(s):

Solar Wind ◽

High Frequency ◽

Interplanetary Space ◽

Solar Wind Plasma ◽

Radial Dependence ◽

Physical Processes ◽

Temperature Anisotropy ◽

Mhd Turbulence ◽

Radial Evolution ◽

Inner Heliosphere

<p>Radial alignments between pairs of spacecraft is the only way to observationally investigate the turbulent evolution of the solar wind as it expands throughout interplanetary space. On September 2020 Parker Solar Probe (PSP) and Solar Orbiter (SolO) were nearly perfectly radially aligned, with PSP orbiting around its perihelion at 0.1 au (and crossing the nominal Alfv&#233;n point) and SolO at 1 au. PSP/SolO joint observations of the same solar wind plasma allow the extraordinary and unprecedented opportunity to study how the turbulence properties of the solar wind evolve in the inner heliosphere over the wide distance of 0.9 au. The radial evolution of (i) the MHD properties (such as radial dependence of low- and high-frequency breaks, compressibility, Alfv&#233;nic content of the fluctuations), (ii) the polarization status, (iii) the presence of wave modes at kinetic scale as well as their distribution in the plasma instability-temperature anisotropy plane are just few instances of what can be addressed. Of furthest interest is the study of whether and how the cascade transfer and dissipation rates evolve with the solar distance, since this has great impact on the fundamental plasma physical processes related to the heating of the solar wind. In this talk I will present some of the results obtained by exploiting the PSP/SolO alignment data.</p>

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A Global Survey of Geospace Electrons with eVlasiator: First Results

10.5194/egusphere-egu21-10638 ◽

2021 ◽

Author(s):

Markku Alho ◽

Markus Battarbee ◽

Yann Pfau-Kempf ◽

Urs Ganse ◽

Lucile Turc ◽

...

Keyword(s):

Solar Wind ◽

Spatial Resolution ◽

Kinetic Models ◽

Electron Distribution ◽

State Of The Art ◽

Distribution Functions ◽

Upper Atmosphere ◽

Electron Precipitation ◽

Gas Dynamic ◽

First Results

<div> <p>Models of the&#160;geospace&#160;plasma environment have been proceeding towards more realistic descriptions of the solar wind&#8212;magnetosphere interaction, from gas-dynamic to MHD and hybrid ion-kinetic models such as the state-of-the-art&#160;Vlasiator&#160;model.&#160;Advances in computational capabilities have enabled global&#160;simulations of detailed physics, but the electron scale has so far been out of reach in a truly global setting.&#160;</p> </div><div> <p>In this work we present results from eVlasiator, an offshoot of the Vlasiator model, showing first results from a global 2D+3V kinetic electron geospace simulation. Despite truncation of some electron physics and use of ion-scale spatial resolution, we show that realistic electron distribution functions are obtainable within the magnetosphere and describe these in relation to MMS observations. Electron precipitation to the upper atmosphere from these velocity distributions is estimated.</p> </div>

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First Results from Swan Lyman α Solar Wind Mapper on SOHO

The First Results from SOHO ◽

10.1007/978-94-011-5236-5_40 ◽

1997 ◽

pp. 737-770

Author(s):

J. L. Bertaux ◽

E. Quémerais ◽

R. Lallement ◽

E. KyröLä ◽

W. Schmidt ◽

...

Keyword(s):

Solar Wind ◽

First Results

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Modelling the solar wind interaction with Mercury by a quasi-neutral hybrid model

Annales Geophysicae ◽

10.5194/angeo-21-2133-2003 ◽

2003 ◽

Vol 21 (11) ◽

pp. 2133-2145 ◽

Cited By ~ 74

Author(s):

E. Kallio ◽

P. Janhunen

Keyword(s):

Solar Wind ◽

Plasma Physics ◽

Hybrid Model ◽

Space Plasma ◽

Physical Processes ◽

Space Plasma Physics ◽

Solar Wind Interaction ◽

Plasma Parameters ◽

Advantages And Disadvantages ◽

Self Consistent

Abstract. Quasi-neutral hybrid model is a self-consistent modelling approach that includes positively charged particles and an electron fluid. The approach has received an increasing interest in space plasma physics research because it makes it possible to study several plasma physical processes that are difficult or impossible to model by self-consistent fluid models, such as the effects associated with the ions’ finite gyroradius, the velocity difference between different ion species, or the non-Maxwellian velocity distribution function. By now quasi-neutral hybrid models have been used to study the solar wind interaction with the non-magnetised Solar System bodies of Mars, Venus, Titan and comets. Localized, two-dimensional hybrid model runs have also been made to study terrestrial dayside magnetosheath. However, the Hermean plasma environment has not yet been analysed by a global quasi-neutral hybrid model. In this paper we present a new quasi-neutral hybrid model developed to study various processes associated with the Mercury-solar wind interaction. Emphasis is placed on addressing advantages and disadvantages of the approach to study different plasma physical processes near the planet. The basic assumptions of the approach and the algorithms used in the new model are thoroughly presented. Finally, some of the first three-dimensional hybrid model runs made for Mercury are presented. The resulting macroscopic plasma parameters and the morphology of the magnetic field demonstrate the applicability of the new approach to study the Mercury-solar wind interaction globally. In addition, the real advantage of the kinetic hybrid model approach is to study the property of individual ions, and the study clearly demonstrates the large potential of the approach to address these more detailed issues by a quasi-neutral hybrid model in the future.Key words. Magnetospheric physics (planetary magnetospheres; solar wind-magnetosphere interactions) – Space plasma physics (numerical simulation studies)

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Theoretical Interpretation of Traveling Interplanetary Phenomena and Their Solar Origins

Symposium - International Astronomical Union ◽

10.1017/s0074180900067966 ◽

1980 ◽

Vol 91 ◽

pp. 443-458 ◽

Cited By ~ 3

Author(s):

S. T. Wu

Keyword(s):

Solar Wind ◽

Wave Propagation ◽

Interplanetary Shock ◽

Theoretical Interpretation ◽

Theoretical Studies ◽

Interplanetary Shocks ◽

Physical Processes ◽

Mathematical Methods ◽

Microscopic Approach ◽

Alternative Approaches

Recent theoretical studies on Traveling Interplanetary Phenomena (TIP) and their relation or presumed relation to their solar origins will be reviewed. An attempt is made to outline the theoretical studies in the context of mathematical methods and physical processes. The following alternative approaches are examined: analytical vs. numerical methods; magnetohydrodynamics vs. hydrodynamics; processes with or without dissipation; continuum (macroscopic) vs. the kinetic (microscopic) approach. In particular, the flare-generated interplanetary shocks are used as examples to illustrate these theoretical studies within the context of TIP. Some emphasis will be placed on MHD wave propagation through the inner corona and its maturity to a fully-developed interplanetary shock. Further, their propagation and the disturbing effects on the solar wind will be considered. Cases concerning the classification and characteristics of blast-produced shocks and long-lasting ejecta are also discussed in the context of numerical simulations.

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