326 citations · 4.6k across the 86 of their papers we have counts for
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Limits on Alpha Particle Temperature Anisotropy and Differential Flow from Kinetic Instabilities: Solar Wind Observations
Sofiane Bourouaine, Daniel Verscharen, Benjamin D. G. Chandran +2
Previous studies have shown that the observed temperature anisotropies of protons and alpha particles in the solar wind are constrained by theoretical thresholds for pressure-aniso…
Direct Numerical Simulations of Reflection-Driven, Reduced MHD Turbulence from the Sun to the Alfven Critical Point
Jean C Perez, Benjamin D. G. Chandran
We present direct numerical simulations of inhomogeneous reduced magnetohydrodynamic (RMHD) turbulence between the Sun and the Alfvén critical point. These are the first such simul…
Perpendicular Ion Heating by Reduced Magnetohydrodynamic Turbulence
Qian Xia, Jean C. Perez, Benjamin D. G. Chandran +1
Recent theoretical studies argue that the rate of stochastic ion heating in low-frequency Alfvén-wave turbulence is given by , where is…
The Efficiency of Second-Order Fermi Acceleration by Weakly Compressible MHD Turbulence
Jacob W. Lynn, Eliot Quataert, Benjamin D. G. Chandran +1
We investigate the effects of pitch-angle scattering on the efficiency of particle heating and acceleration by MHD turbulence using phenomenological estimates and simulations of no…
Instabilities Driven by the Drift and Temperature Anisotropy of Alpha Particles in the Solar Wind
Daniel Verscharen, Sofiane Bourouaine, Benjamin D. G. Chandran
We investigate the conditions under which parallel-propagating Alfvén/ion-cyclotron (A/IC) waves and fast-magnetosonic/whistler (FM/W) waves are driven unstable by the differential…
Stochastic Heating, Differential Flow, and the Alpha-to-Proton Temperature Ratio in the Solar Wind
B. D. G. Chandran, D. Verscharen, E. Quataert +3
We extend previous theories of stochastic ion heating to account for the motion of ions along the magnetic field. We derive an analytic expression for the ion-to-proton perpendicul…
A Parallel-Propagating Alfvénic Ion-Beam Instability in the High-Beta Solar Wind
Daniel Verscharen, Sofiane Bourouaine, Benjamin D. G. Chandran +1
We investigate the conditions under which parallel-propagating Alfvén/ion-cyclotron waves are driven unstable by an isotropic () population of alpha p…
Observational Test of Stochastic Heating in Low- Fast Solar Wind Streams
Sofiane Bourouaine, Benjamin D. G. Chandran
Spacecraft measurements show that protons undergo substantial perpendicular heating during their transit from the Sun to the outer heliosphere. In this paper, we use {\em Helios~2}…
The Dispersion Relations and Instability Thresholds of Oblique Plasma Modes in the Presence of an Ion Beam
Daniel Verscharen, Benjamin D. G. Chandran
An ion beam can destabilize Alfvén/ion-cyclotron waves and magnetosonic/whistler waves if the beam speed is sufficiently large. Numerical solutions of the hot-plasma dispersion rel…