Search Publications
Anisotropy of Solar Wind Turbulence in the Inner Heliosphere at Kinetic Scales: PSP Observations
Chen, Christopher H. K.; He, Jiansen; Bale, Stuart D. +5 more
The anisotropy of solar wind turbulence is a critical issue in understanding the physics of energy transfer between scales and energy conversion between fields and particles in the heliosphere. Using the measurement of Parker Solar Probe (PSP), we present an observation of the anisotropy at kinetic scales in the slow, Alfvénic, solar wind in the i…
Characteristics of Magnetic Holes in the Solar Wind Revealed by Parker Solar Probe
Zhang, J.; Huang, S. Y.; Xu, S. B. +6 more
We present a statistical analysis for the characteristics and radial evolution of linear magnetic holes (LMHs) in the solar wind from 0.166 to 0.82 au using Parker Solar Probe observations of the first two orbits. It is found that the LMHs mainly have a duration less than 25 s and the depth is in the range from 0.25 to 0.7. The durations slightly …
Kinetic Alfvén Waves in Space Plasma Environment with κ-electrons
Lakhina, G. S.; Singh, S. V.; Barik, K. C.
A resonant instability of kinetic Alfvén waves (KAWs) driven by ion beam is discussed through a theoretical model encompassing Maxwellian background ions and beam ions and non-Maxwellian κ-electrons. The ion beam velocity alone as a source is able to excite the KAWs up to a significant growth. The non-Maxwellian parameter κ impedes the growth of K…
Acceleration of Ring Current Protons Driven by Magnetosonic Waves: Comparisons of Test Particle Simulations with Quasilinear Calculations
Fu, Song; Ge, Yasong
Wave-particle interactions play important roles in local acceleration and pitch angle scattering loss of charged particle dynamics in astrophysics and space physics, and energy transfer between plasma waves and particles is a key problem in plasma physics. Using full relativistic test particle simulations, we quantitatively evaluate the magnetoson…
Detecting Reconnection Sites Using the Lorentz Transformations for Electromagnetic Fields
Lapenta, Giovanni
We take a pragmatic definition of reconnection to find locations where a reconnection electric field causes an E × B drift that carries two components of the magnetic field toward their elimination. With this in mind as our target, we observe that such locations can be found using a new indicator: the velocity of the Lorentz transformation that el…
Prediction of Soft Proton Intensities in the Near-Earth Space Using Machine Learning
Tiengo, Andrea; Allen, Robert C.; Gastaldello, Fabio +14 more
The spatial distribution of energetic protons contributes to the understanding of magnetospheric dynamics. Based upon 17 yr of the Cluster/RAPID observations, we have derived machine-learning-based models to predict the proton intensities at energies from 28 to 962 keV in the 3D terrestrial magnetosphere at radial distances between 6 and 22 R…
Complexity of Magnetic-field Turbulence at Reconnection Exhausts in the Solar Wind at 1 au
Miranda, Rodrigo A.; Valdivia, Juan A.; Chian, Abraham C. -L. +1 more
Magnetic reconnection is a complex mechanism that converts magnetic energy into particle kinetic energy and plasma thermal energy in space and astrophysical plasmas. In addition, magnetic reconnection and turbulence appear to be intimately related in plasmas. We analyze the magnetic-field turbulence at the exhaust of four reconnection events detec…
The Solar-cycle Variations of the Anisotropy of Taylor Scale and Correlation Scale in the Solar Wind Turbulence
Zhou, G.; He, H. -Q.
The field-aligned anisotropy of the solar wind turbulence, which is quantified by the ratio of the parallel to the perpendicular correlation (and Taylor) length scales, is determined by simultaneous two-point correlation measurements during the time period 2001-2017. Our results show that the correlation scale along the magnetic field is the large…
A Perspective on the Scaling of Magnetosheath Turbulence and Effects of Bow Shock Properties
Voitcu, Gabriel; Echim, Marius; Teodorescu, Eliza
We analyze magnetic field data from two magnetosheath crossings, representative of a larger collection of similar cases in the database of the Cluster spacecraft. We apply a novel data analysis method to identify the power-law behavior of the structure functions and to find the validity range of the power-law scaling. We validate the technique wit…
Radiation Belt Response to Fast Reverse Shock at Geosynchronous Orbit
Kanekal, Shrikanth G.; Sibeck, David; Bhaskar, Ankush +5 more
Fast reverse shocks (FRSs) cause the magnetosphere to expand, by contrast to the well-known compressions caused by the impact of fast forward shocks (FFS). Usually, FFSs are more geoeffective than FRSs, and consequently the inner magnetosphere dynamic responses to both shock types can be quite different. In this study, we investigate for the first…