TT22B:
Solar Wind Turbulence: Latest Advances and New Insights
TT22B:
Solar Wind Turbulence: Latest Advances and New Insights
Solar Wind Turbulence: Latest Advances and New Insights
Submit an Abstract to this Session
Session ID#: 52536
Session Description:
Turbulence plays a fundamental role in the transport and dissipation
of energy and the scattering and acceleration of particles in all
astrophysical plasmas. The solar wind provides the closest example of
a turbulent plasma in which all of the above processes are occurring.
Solar wind streams observed in-situ are dominated by low frequency
fluctuations displaying a power spectrum with clear signatures of an
turbulent cascade. In some instances, the power law indices approach
the well-known values from hydrodynamic turbulence described by
Kolmogorov. However, the velocity and magnetic field fluctuations in
the solar wind are often highly correlated – especially in the fast
solar wind streams at solar minimum - in the sense of large amplitude
Alfvén waves propagating away from the Sun. At the low frequencies
where magnetohydrodynamic turbulence should be valid, the energy
cascade process is mediated by nonlinear interactions between inward
and outward propagating Alfvénic fluctuations, so the presence of
multiple solar wind states, with various degrees of turbulent
relaxation, provides a laboratory in which theories of Alfvénic
turbulence may be tested directly. This tutorial talk will review
theories and observations of solar wind turbulence and its possible
dynamical role in the acceleration of the wind. It will highlight the
open issues and the potential for discovery from Parker Solar Probe
and other inner heliospheric explorers.
of energy and the scattering and acceleration of particles in all
astrophysical plasmas. The solar wind provides the closest example of
a turbulent plasma in which all of the above processes are occurring.
Solar wind streams observed in-situ are dominated by low frequency
fluctuations displaying a power spectrum with clear signatures of an
turbulent cascade. In some instances, the power law indices approach
the well-known values from hydrodynamic turbulence described by
Kolmogorov. However, the velocity and magnetic field fluctuations in
the solar wind are often highly correlated – especially in the fast
solar wind streams at solar minimum - in the sense of large amplitude
Alfvén waves propagating away from the Sun. At the low frequencies
where magnetohydrodynamic turbulence should be valid, the energy
cascade process is mediated by nonlinear interactions between inward
and outward propagating Alfvénic fluctuations, so the presence of
multiple solar wind states, with various degrees of turbulent
relaxation, provides a laboratory in which theories of Alfvénic
turbulence may be tested directly. This tutorial talk will review
theories and observations of solar wind turbulence and its possible
dynamical role in the acceleration of the wind. It will highlight the
open issues and the potential for discovery from Parker Solar Probe
and other inner heliospheric explorers.
Primary Presenter: Marco C M Velli, University of California Los Angeles, Los Angeles, CA, United States
Presenter: Raffaella D'Amicis, INAF-Istituto di Astrofisica e Planetologia Spaziali, Roma, Italy
Cross-Listed:
- NG - Nonlinear Geophysics
- SH - SPA-Solar and Heliospheric Physics
Index Terms:
2149 MHD waves and turbulence [INTERPLANETARY PHYSICS]
2164 Solar wind plasma [INTERPLANETARY PHYSICS]
7863 Turbulence [SPACE PLASMA PHYSICS]
Abstracts Submitted to this Session:
See more of: Tutorial Talks