Related papers: Modification of Proton Velocity Distributions by A…
Although the mechanisms responsible for heating the Sun's corona and accelerating the solar wind are still being actively investigated, it is largely accepted that photospheric motions provide the energy source and that the magnetic field…
We solve the problem of propagation and dissipation of Alfvenic turbulence in a model solar atmosphere consisting of a static photosphere and chromosphere, transition region, and open corona and solar wind, using a phenomenological model…
We present a comprehensive model of the global properties of Alfven waves in the solar atmosphere and fast solar wind. Linear non-WKB wave transport equations are solved from the photosphere to 4 AU, and for wave periods ranging from 3…
Stellar winds from active solar type stars can play a crucial role in removal of stellar angular momentum and erosion of planetary atmospheres. However, major wind properties except for mass loss rates cannot be directly derived from…
We present multicomponent solar wind models self-consistently incorporating the contribution from dissipationless, monochromatic, finite-wavelength (non-WKB), hydromagnetic, toroidal Alfv\'en waves, which are coupled to the flow only…
The expanding solar wind plasma ubiquitously exhibits anisotropic non-thermal particle velocity distributions. Typically, proton Velocity Distribution Functions (VDFs) show the presence of a core and a field-aligned beam. Novel observations…
The solar wind is the extension of the Sun's hot and ionized corona, and it exists in a state of continuous expansion into interplanetary space. The radial distance at which the wind's outflow speed exceeds the phase speed of Alfvenic and…
The propagation of dissipationless, hydromagnetic, non-WKB, purely toroidal Alfv\'en waves in a realistic background three-fluid solar wind with axial symmetry and differential proton-alpha flow is investigated. The wave equations are…
This paper employs a recent turbulent heating prescription to predict the ratio of proton-to-total heating due to the kinetic dissipation of Alfvenic turbulence as a function of heliocentric distance. Comparing to a recent empirical…
Nonlinear energy transfer and dissipation in Alfv\'en wave turbulence are analyzed in the first gyrokinetic simulation spanning all scales from the tail of the MHD range to the electron gyroradius scale. For typical solar wind parameters at…
Aims: Propagation and energy transfer of torsional Alfv\'en waves in solar magnetic flux tubes of axial symmetry is studied. Methods: An analytical model of a solar magnetic flux tube of axial symmetry is developed by specifying a magnetic…
Close to Earth the solar wind is usually super-Alfv\'enic, i.e. the speed of the solar wind is much larger than the Alfv\'en speed. However, in the lower coronal regions, the solar wind is mostly sub-Alfv\'enic. With the Parker Solar Probe…
The nature of subproton scale fluctuations in the solar wind is an open question, partly because two similar types of electromagnetic turbulence can occur: kinetic Alfven turbulence and whistler turbulence. These two possibilities, however,…
Understanding the mechanism(s) of the solar wind acceleration is important in astrophysics and geophysics. A promising model of the solar wind acceleration is known as the wave/turbulence-driven (WTD) model, in which Alfv\'en waves feed…
The heating and acceleration of the solar wind remains one of the fundamental unsolved problems in heliophysics. It is usually observed that the proton temperature $T_i$ is highly correlated with the solar wind speed $V_{SW}$, while the…
We study the behaviour and properties of the solar wind using a 2.5D Alfv\'en wave driven wind model. We first systematically compare the results of an Alfv\'en wave (AW) driven wind model with a polytropic approach. Polytropic…
One proposed mechanism for heating the solar wind, from close to the sun to beyond 10 AU, invokes low-frequency, oblique, Alfven-wave turbulence. Because small-scale oblique Alfven waves (kinetic Alfven waves) are compressive, the measured…
Protons in the solar corona and heliosphere exhibit anisotropic velocity distributions, violation of magnetic moment conservation, and a general lack of thermal equilibrium with the other particle species. There is no agreement about the…
An accurate assessment of the Sun's angular momentum (AM) loss rate is an independent constraint for models that describe the rotation evolution of Sun-like stars. In-situ measurements of the solar wind taken by Parker Solar Probe (PSP), at…
Plasma kinetic waves and alpha-proton differential flow are two important subjects on the topic of evolution of the solar wind. Based on the Wind data during 2005-2015, this paper reports that the occurrence of electromagnetic cyclotron…