424 citations · 2.6k across the 108 of their papers we have counts for
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In-situ measurements of space plasma: recent progress and future challenges
Daniel Verscharen
Space plasmas like the solar wind or the Earth's space environment offer unique opportunities to observe fundamental plasma processes and their impact in situ. With modern space in…
Transport of electrons in tangled magnetic fields
Daniel Verscharen, Natasha Jeffrey, Anton Artemyev +6
Cosmic magnetic fields are typically inhomogeneous and often highly tangled due to large-scale plasma flows, turbulence, and instabilities. If the variations in the magnetic field…
Langmuir Wave Excitation in Solar-wind Magnetic Holes
Jingting Liu, Daniel Verscharen, Jesse Coburn +8
Magnetic holes are structures commonly observed in various space plasma environments throughout the solar system, including the solar wind. These structures are characterized by a…
How does the limited resolution of space plasma analyzers affect the accuracy of space plasma measurements?
Georgios Nicolaou, Charalambos Ioannou, Christopher Owen +3
We investigate the systematic errors in measured plasma velocity distribution functions and their corresponding velocity moments, arising from the limited energy and angular resolu…
Temperature anisotropy instabilities driven by intermittent velocity shears in the solar wind
Simon Opie, Daniel Verscharen, Christopher H. K. Chen +5
Where and under what conditions the transfer of energy between electromagnetic fields and particles takes place in the solar wind remains an open question. We investigate the condi…
The impact of non-equilibrium plasma distributions on solar wind measurements by Vigil's Plasma Analyser
Hongjie Zhang, Daniel Verscharen, Georgios Nicolaou
In order to protect society from space weather impacts, we must monitor space weather and obtain early warnings for extreme events if possible. For this purpose, the European Space…
Regulation of Proton- Differential Flow by Compressive Fluctuations and Ion-scale Instabilities in the Solar Wind
Xingyu Zhu, Daniel Verscharen, Jiansen He +2
Large-scale compressive slow-mode-like fluctuations can cause variations in the density, temperature, and magnetic-field magnitude in the solar wind. In addition, they also lead to…
Magnetic reconnection as an erosion mechanism for magnetic switchbacks
G. H. H. Suen, C. J. Owen, D. Verscharen +3
Magnetic switchbacks are localised polarity reversals in the radial component of the heliospheric magnetic field. Observations from Parker Solar Probe (PSP) have shown that they ar…
The essential role of multi-point measurements in investigations of turbulence, three-dimensional structure, and dynamics: the solar wind beyond single scale and the Taylor Hypothesis
W. H. Matthaeus, S. Adhikari, R. Bandyopadhyay +49
Space plasmas are three-dimensional dynamic entities. Except under very special circumstances, their structure in space and their behavior in time are not related in any simple way…
Conditions for proton temperature anisotropy to drive instabilities in the solar wind
Simon Opie, Daniel Verscharen, Christopher H. K. Chen +2
Using high-resolution data from Solar Orbiter, we investigate the plasma conditions necessary for the proton temperature anisotropy driven mirror-mode and oblique firehose instabil…
Electron-driven instabilities in the solar wind
Daniel Verscharen, Benjamin D. G. Chandran, Elisabetta Boella +9
The electrons are an essential particle species in the solar wind. They often exhibit non-equilibrium features in their velocity distribution function. These include temperature an…
The Kinetic Expansion of Solar-Wind Electrons: Transport Theory and Predictions for the very Inner Heliosphere
Seong-Yeop Jeong, Daniel Verscharen, Christian Vocks +9
We propose a transport theory for the kinetic evolution of solar-wind electrons in the heliosphere. We derive a gyro-averaged kinetic transport equation that accounts for the spher…
Observations of rapidly growing whistler waves in front of space plasma shock
Jiansen He, Xingyu Zhu, Qiaowen Luo +8
Whistler mode wave is a fundamental perturbation of electromagnetic fields and plasmas in various environments including planetary space, laboratory and astrophysics. The origin an…
Whistler instability driven by the sunward electron deficit in the solar wind
Laura Berčič, Daniel Verscharen, Christopher J. Owen +18
Solar wind electrons play an important role in the energy balance of the solar wind acceleration by carrying energy into interplanetary space in the form of electron heat flux. The…
Precision Electron Measurements in the Solar Wind at 1 au from NASA's Wind Spacecraft
Chadi S. Salem, Marc Pulupa, Stuart D. Bale +1
This work aims to characterize precisely and systematically the non-thermal characteristics of the electron Velocity Distribution Function (eVDF) in the solar wind at 1 au using da…
The solar-wind angular-momentum flux observed during Solar Orbiter's first orbit
Daniel Verscharen, David Stansby, Adam J. Finley +19
Aims: We present the first measurements of the solar-wind angular-momentum (AM) flux recorded by the Solar Orbiter spacecraft. Our aim is the validation of these measurements to su…
Magnetic Field Reconstruction for a Realistic Multi-Point, Multi-Scale Spacecraft Observatory
Theodore Broeren, Kristopher Klein, Jason TenBarge +3
Future in situ space plasma investigations will likely involve spatially distributed observatories comprised of multiple spacecraft, beyond the four and five spacecraft configurati…
Three-dimensional magnetic reconnection in particle-in-cell simulations of anisotropic plasma turbulence
Jeffersson A. Agudelo Rueda, Daniel Verscharen, Robert T. Wicks +6
We use 3D fully kinetic particle-in-cell simulations to study the occurrence of magnetic reconnection in a simulation of decaying turbulence created by anisotropic counter-propagat…
Possible coexistence of kinetic Alfvén and ion Bernstein modes in sub-ion scale compressive turbulence in the solar wind
Owen Wyn Roberts, Daniel Verscharen, Yasuhito Narita +3
We investigate compressive turbulence at sub-ion scales with measurements from the Magnetospheric MultiScale Mission. The tetrahedral configuration and high time resolution density…
Wave Composition, Propagation, and Polarization of MHD Turbulence within 0.3AU as Observed by PSP
Xingyu Zhu, Jiansen He, Daniel Verscharen +2
Turbulence, a ubiquitous phenomenon in interplanetary space, is crucial for the energy conversion of space plasma at multiple scales. This work focuses on the propagation, polariza…
A Quasi-Linear Diffusion Model for Resonant Wave-Particle Instability in Homogeneous Plasma
Seong-Yeop Jeong, Daniel Verscharen, Robert T. Wicks +1
In this paper, we develop a model to describe the generalized wave-particle instability in a quasi-neutral plasma. We analyze the quasi-linear diffusion equation for particles by e…
Polytropic Behavior of Solar Wind Protons Observed by Parker Solar Probe
Georgios Nicolaou, George Livadiotis, Robert T. Wicks +2
A polytropic process describes the transition of a fluid from one state to another through a specific relationship between the fluid density and temperature. The value of the polyt…
Statistics of Solar Wind Electron Breakpoint Energies Using Machine Learning Techniques
Mayur R. Bakrania, I. Jonathan Rae, Andrew P. Walsh +4
Solar wind electron velocity distributions at 1 au consist of a thermal "core" population and two suprathermal populations: "halo" and "strahl". The core and halo are quasi-isotrop…
Magnetic Energy Transfer and Distribution between Protons and Electrons for Alfvénic Waves at Kinetic Scales in Wavenumber Space
Die Duan, Jiansen He, Honghong wu +1
Turbulent dissipation is considered a main source of heating and acceleration in cosmological plasmas. The alternating current Joule-like term, , is used…