Search Publications

Narrowband Large Amplitude Whistler-mode Waves in the Solar Wind and Their Association with Electrons: STEREO Waveform Capture Observations
DOI: 10.3847/1538-4357/ab961f Bibcode: 2020ApJ...897..126C

Breneman, A. W.; Cattell, C. A.; Short, B. +1 more

Large amplitude (up to 70 mV m-1) whistler-mode waves at frequencies of ∼0.2-0.4 fce (electron cyclotron frequency) are frequently observed in the solar wind. The waves are obliquely propagating at angles close to the resonance cone, resulting in significant electric fields parallel to the background magnetic field, enabling …

2020 The Astrophysical Journal
Cluster 32
Whistler Waves and Electron Properties in the Inner Heliosphere: Helios Observations
DOI: 10.3847/1538-4357/ab94a1 Bibcode: 2020ApJ...897..118J

Alexandrova, Olga; de Wit, Thierry Dudok; Maksimovic, Milan +4 more

We present the analysis of narrowband whistler wave signatures observed in the inner heliosphere (0.3-1 au). These signatures are bumps in the spectral density in the 10-200 Hz frequency range of the AC magnetic field as measured by the search coil magnetometer on board the Helios 1 spacecraft. We show that the majority of whistler signatures are …

2020 The Astrophysical Journal
Cluster 29
Monitoring the Spatio-temporal Evolution of a Reconnection X-line in Space
DOI: 10.3847/2041-8213/abad2c Bibcode: 2020ApJ...899L..34W

Vaivads, A.; Wang, Z.; Cao, J. B. +3 more

Inherently, magnetic reconnection—the process responsible for stellar flares and magnetospheric substorms—is very dynamic in space, owing to magnetic fluctuations and unsteady inflows. However, this process was always explained as a static picture in spacecraft measurements, neglecting the temporal evolution. This picture is not correct. Here we p…

2020 The Astrophysical Journal
Cluster 26
Direct Measurement of the Solar-wind Taylor Microscale Using MMS Turbulence Campaign Data
DOI: 10.3847/1538-4357/ab9ebe Bibcode: 2020ApJ...899...63B

Strangeway, Robert J.; Russell, Christopher T.; Chasapis, Alexandros +7 more

Using the novel Magnetospheric Multiscale (MMS) mission data accumulated during the 2019 MMS Solar Wind Turbulence Campaign, we calculate the Taylor microscale (λT) of the turbulent magnetic field in the solar wind. The Taylor microscale represents the onset of dissipative processes in classical turbulence theory. However, an accurate e…

2020 The Astrophysical Journal
Cluster 23
Magnetosheath Jets and Plasmoids: Characteristics and Formation Mechanisms from Hybrid Simulations
DOI: 10.3847/2041-8213/abad2b Bibcode: 2020ApJ...900L...6P

Blanco-Cano, Xóchitl; Burgess, David; Trotta, Domenico +2 more

Magnetosheath jets and plasmoids are very common phenomena downstream of Earth's quasi-parallel bow shock. As the increase of the dynamic pressure is one of the principal characteristics of magnetosheath jets, the embedded paramagnetic plasmoids have been considered as an special case of the former. Although the properties of both types of structu…

2020 The Astrophysical Journal
Cluster 23
Numerical Modeling of Suprathermal Electron Transport in the Solar Wind: Effects of Whistler Turbulence
DOI: 10.3847/1538-4357/ab7a93 Bibcode: 2020ApJ...892...95T

Zank, Gary P.; Tang, Bofeng; Kolobov, Vladimir I.

The solar wind electron velocity distribution function deviates significantly from an equilibrium Maxwellian distribution and is composed of a Maxwellian core, a suprathermal halo, a field-aligned component strahl, and a higher-energy superhalo. Wave-particle interactions associated with whistler wave turbulence are introduced into the kinetic tra…

2020 The Astrophysical Journal
Cluster Ulysses 18
Electron Temperature Anisotropy and Electron Beam Constraints from Electron Kinetic Instabilities in the Solar Wind
DOI: 10.3847/1538-4357/abb3ca Bibcode: 2020ApJ...902...59S

Xie, Huasheng; Wu, Dejin; Sun, Heyu +2 more

Electron temperature anisotropies and electron beams are nonthermal features of the observed nonequilibrium electron velocity distributions in the solar wind. In collision-poor plasmas these nonequilibrium distributions are expected to be regulated by kinetic instabilities through wave-particle interactions. This study considers electron instabili…

2020 The Astrophysical Journal
Cluster 17
Fluid Theory of Coherent Magnetic Vortices in High-β Space Plasmas
DOI: 10.3847/1538-4357/ab8a45 Bibcode: 2020ApJ...896....8J

Alexandrova, Olga; Maksimović, Milan; Jovanović, Dušan +1 more

In situ observations in Earth's and Saturn's magnetosheaths and in the solar wind reveal the presence of Alfvén vortices as intermittent structures in the range of scales from fluid lengths down to a few ion lengths. The density and the magnetic field associated with them appear to be compressible for higher plasma betas. Until now, only incompres…

2020 The Astrophysical Journal
Cluster 8
Effects of Solar Activity on Taylor Scale and Correlation Scale in Solar Wind Magnetic Fluctuations
DOI: 10.3847/2041-8213/abaaa9 Bibcode: 2020ApJ...899L..32Z

Zhou, G.; Wan, W.; He, H. -Q.

The correlation scale and the Taylor scale are evaluated for interplanetary magnetic field fluctuations from two-point, single time correlation function using the Advanced Composition Explorer (ACE), Wind, and Cluster spacecraft data during the time period from 2001 to 2017, which covers over an entire solar cycle. The correlation scale and the Ta…

2020 The Astrophysical Journal
Cluster 8
Relationship between Current Filaments and Turbulence During a Turbulent Reconnection
DOI: 10.3847/2041-8213/ab61fe Bibcode: 2020ApJ...888L..16C

Yu, Y.; Chen, Z. Z.; Chen, F. +1 more

Both magnetic reconnection and turbulence can play crucial roles in space plasmas. The current layers, developing during magnetic reconnection, can collapse into various small-scale coherent structures, such as current filaments. These current filaments can significantly modulate the kinetic-scale turbulence. However, the quantitative correlation …

2020 The Astrophysical Journal
Cluster 6