Magnetic Field Binning and Display of Ion Composition Data.

1995 ◽  
Author(s):  
Dennis E. Delorey ◽  
Paul N. Pruneau ◽  
John R. Palys
Keyword(s):  
Magnetic Field ◽  
Ion Composition ◽  
Composition Data

The effect of plasmaspheric material on magnetopause reconnection

2020 ◽  
Author(s):  
Stephen Fuselier ◽  
Stein Haaland ◽  
Paul Tenfjord ◽  
David Malaspina ◽  
James Burch ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Low Temperature ◽  
Magnetic Reconnection ◽  
Plasma Wave ◽  
Outer Part ◽  
Field Measurements ◽  
Ion Composition ◽  
The Earth ◽  
Magnetospheric Multiscale ◽  
Magnetic Field Measurements

<p>The Earth’s plasmasphere contains cold (~eV energy) dense (>100 cm<sup>-3</sup>) plasma of ionospheric origin. The primary ion constituents of the plasmasphere are H<sup>+ </sup>and He<sup>+</sup>, and a lower concentration of O<sup>+</sup>. The outer part of the plasmasphere, especially on the duskside of the Earth, drains away into the dayside outer magnetosphere when geomagnetic activity increases. Because of its high density and low temperature, this plasma has the potential to modify magnetic reconnection at the magnetopause. To investigate the effect of plasmaspheric material at the magnetopause, Magnetospheric Multiscale (MMS) data are surveyed to identify magnetopause crossings with the highest He<sup>+</sup>densities. Plasma wave, ion, and ion composition data are used to determine densities and mass densities of this plasmaspheric material and the magnetosheath plasma adjacent to the magnetopause. These measurements are combined with magnetic field measurements to determine how the highest density plasmaspheric material in the MMS era may affect reconnection at the magnetopause.</p>

Sulfuric acid vapour derivations from negative ion composition data between 25 and 34 km

1983 ◽  
Vol 10 (4) ◽  
pp. 329-332 ◽  
Author(s):  
E. Arijs ◽  
D. Nevejans ◽  
J. Ingels ◽  
P. Frederick
Keyword(s):  
Sulfuric Acid ◽  
Negative Ion ◽  
Ion Composition ◽  
Composition Data

scholarly journals Variable Ion Compositions of Solar Energetic Particle Events in the Inner Heliosphere: A Field Line Braiding Model with Compound Injections

2022 ◽  
Vol 924 (1) ◽  
pp. 22
Author(s):  
Fan Guo ◽  
Lulu Zhao ◽  
Christina M. S. Cohen ◽  
Joe Giacalone ◽  
R. A. Leske ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Energetic Particle ◽  
Radial Distance ◽  
Solar Energetic Particle ◽  
The Sun ◽  
Ion Composition ◽  
Source Regions ◽  
Solar Energetic Particle Events ◽  
Composition Ratios ◽  
Inner Heliosphere

Abstract We propose a model for interpreting highly variable ion composition ratios in solar energetic particle (SEP) events recently observed by the Parker Solar Probe (PSP) at 0.3–0.45 au. We use numerical simulations to calculate SEP propagation in a turbulent interplanetary magnetic field with a Kolmogorov power spectrum from large scales down to the gyration scale of energetic particles. We show that when the source regions of different species are offset by a distance comparable to the size of the source regions, the observed energetic particle composition He/H can be strongly variable over more than two orders of magnitude, even if the source ratio is at the nominal value. Assuming a 3He/4He source ratio of 10% in impulsive 3He-rich events and the same spatial offset of the source regions, the 3He/4He ratio at observation sites also vary considerably. The variability of the ion composition ratios depends on the radial distance, which can be tested by observations made at different radial locations. We discuss the implications of these results on the variability of ion composition of impulsive events and on further PSP and Solar Orbiter observations close to the Sun.

Thin current sheets of sub-ion scales observed in planetary magnetotails

2021 ◽  
Author(s):  
Elena Grigorenko ◽  
Makar Leonenko ◽  
Lev Zelenyi ◽  
Helmi Malova ◽  
Victor Popov
Keyword(s):  
Magnetic Field ◽  
Larmor Radius ◽  
High Time Resolution ◽  
Current Layer ◽  
Ion Composition ◽  
Kinetic Description ◽  
Small Component ◽  
Current Sheets ◽  
The Earth ◽  
Plasma Characteristics

<p>Current sheets (CSs) play a crucial role in the storage and conversion of magnetic energy in planetary magnetotails. Spacecraft observations in the terrestrial magnetotail reported that the CS thinning and intensification can result in formation of multiscale current structure in which a very thin and intense current layer at the center of the CS is embedded into a thicker sheet. To describe such CSs fully kinetic description taking into account all peculiarities of non-adiabatic particle dynamics is required. Kinetic description brings kinetic scales to the CS models. Ion scales are controlled by thermal ion Larmor radius, while scales of sub-ion embedded CS are controlled by the topology of magnetic field lines until the electron motion is magnetized by a small component of the magnetic field existing in a very center of the CS. MMS observations in the Earth magnetotail as well as MAVEN observations in the Martian magnetotail with high time resolution revealed the formation of similar multiscale structure of the cross-tail CS in spite of very different local plasma characteristics. We revealed that the typical half‐thickness of the embedded Super Thin Current Sheet (STCSs) observed at the center of the CS in the magnetotails of both planets is much less than the gyroradius of thermal protons. The formation of STCS does not depend on ion composition, density and temperature,  but it is controlled by the small value of the normal component of the magnetic field at the neutral plane. Our analysis showed that there is a good agreement between the spatial scaling of multiscale CSs observed in both magnetotails and the scaling predicted by the quasi-adiabatic model of thin anisotropic CS taking into account the coupling between ion and electron currents. Thus, in spite of the significant differences in the CS formation, ion composition, and plasma characteristics in the Earth’s and Martian magnetotails, similar kinetic features are observed in the CS structures in the magnetotails of both planets. This phenomenon can be explained by the universal principles of nature. The CS once has been formed, then it should be self-consistently supported by the internal coupling of the total current carried by particles in the CS and its magnetic configuration, and as soon as the system achieved the quasi-equilibrium state, it “forgets” the mechanisms of its formation, and its following existence is ruled by the general principles of plasma kinetic described by Vlasov–Maxwell equations.</p><p>This work is supported by the Russian Science Foundation grant № 20-42-04418</p>

Statistical analysis of the accelerated H2O ions above 1 keV: the comet 67P/Churyumov–Gerasimenko observed by the Rosetta spacecraft.

2021 ◽  
Author(s):  
Tsubasa Kotani ◽  
Masatoshi Yamauchi ◽  
Hans Nilsson ◽  
Gabriella Stenberg-Wieser ◽  
Martin Wieser ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Statistical Analysis ◽  
The Sun ◽  
Ion Composition ◽  
Solar Winds ◽  
Comet Activity ◽  
Parallel Acceleration ◽  
Comet 67P ◽  
The Magnetic Field

<p>The ESA/Rosetta spacecraft has studied the comet 67P/Churyumov-Gerasimenko for two years. Rosetta Plasma Consortium's Ion Composition Analyser (RPC/ICA) detected comet-origin water ions that are accelerated to > 100 eV.<span>  </span>Majority of them are interpreted as ordinary pick-up acceleration<span>  </span>by the solar wind electric field perpendicular to the magnetic field during low comet activity [1,2]. As the comet approaches the sun, a comet magnetosphere is formed, where solar winds cannot intrude.</p><p>However,  some water ions are accelerated to > 1 keV even in the magnetosphere [3]. Using RPC/ICA data during two years [4], we investigate the acceleration events > 1 keV where solar winds are not observed, and classify dispersion events with respect to the directions of the sun, the comet, and the magnetic field.<span>  </span>Majority of these water ions show reversed energy-angle dispersion. <span>Results of the investigation also show that these ions are flowing along the (enhanced) magnetic field, indicating that the parallel acceleration occurs in the magnetosphere.</span></p><p>In this meeting, we show a statistical analysis and discuss a possible acceleration mechanism.</p><p><strong>References</strong></p><p>[1] H. Nilsson et al., MNRAS 469, 252 (2017), doi:10.1093/mnras/stx1491</p><p>[2] G. Nicolau et al., MNRAS 469, 339 (2017), doi:10.1093/mnras/stx1621</p><p>[3] T. Kotani et al., EPSC, EPSC2020-576 (2020), https://doi.org/10.5194/epsc2020-576</p><p>[4] H. Nilsson et al., Space Sci. Rev., 128, 671 (2007), DOI: 10.1007/s11214-006-9031-z </p>

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