Observations of cross scale energy transfer in the inner heliosphere by Parker Solar Probe

Abstract

The solar wind, a continuous flow of plasma from the sun, not only shapes the near Earth space environment but also serves as a natural laboratory to study plasma turbulence in conditions that are not achievable in the lab. Starting with the Mariners, for more than five decades, multiple space missions have enabled in-depth studies of solar wind turbulence. Parker Solar Probe (PSP) was launched to explore the origins and evolution of the solar wind. With its state-of-the-art instrumentation and unprecedented close approaches to the sun, PSP is starting a new era of inner heliospheric exploration. In this review we discuss observations of turbulent energy flow across scales in the inner heliosphere as observed by PSP. After providing a quick theoretical overview and a quick recap of turbulence before PSP, we discuss in detail the observations of energy at various scales on its journey from the largest scales to the internal degrees of freedom of the plasma. We conclude with some open ended questions, many of which we hope that PSP will help answer.

On Calculating Diffusion Coefficients Numerically in Synthetic Turbulence Using Particle Pushers

“…approach to generating synthetic turbulence also remains highly relevant. The many recent studies of turbulence as observed by, e.g., Parker Solar Probe (see, e.g., Adhikari et al 2020;Telloni 2021;Parashar & Matthaeus 2022;Huang et al 2023;Lotz et al 2023) provide valuable inputs whereby the transport coefficients of solar energetic particles, for example, may be investigated in the very inner heliosphere. Lastly, it has been shown that cosmic-ray transport coefficients in different astrospheres can potentially play a significant role in the habitability of exoplanets (see, e.g., Herbst et al 2020;Engelbrecht et al 2024).…”

Editorial : Reviews of Modern Plasma Physics: Volume 6

“…Topical collection "Nonlinear Processes in Solar-Terrestrial Plasmas (NLST)" is organized by Tohru Hada, Abraham Chian and Ryoji Matsumoto selected from SG and SA speakers in AAPPS-DPP2021 and published four articles in 2022 (Nariyuki 2022;Dominguez and Utz 2022;Chian et al 2022;Parashar and Matthaeus 2022).…”

Effects of Alpha Particle Fraction on Kinetic Plasma Turbulence

“…Most of these enhancements result from the cascade of energy from large to small scales where this energy is dissipated intermittently. Observations have revealed abundant features of fields fluctuations and plasma anisotropy during the turbulence in the terrestrial magnetosheath (e.g., Retinò et al 2007;Chasapis et al 2017;Huang et al 2021aHuang et al , 2022a, planetary magnetosphere (e.g., Vörös et al 2008;Hadid et al 2015;Tao et al 2015;Ruhunusiri et al 2017;Gershman et al 2019;Bowen et al 2021;Huang et al 2022aHuang et al , 2021b, and solar wind (e.g., Huang et al 2020Huang et al , 2021bHuang et al , 2022bSioulas et al 2022;Parashar & Matthaeus 2022;Zhang et al 2022aZhang et al , 2022b. The fundamental physics of the energy cascade and resulting processes in kinetic plasmas has been previously explored at both magnetohydrodynamic (MHD; e.g., Matthaeus & Goldstein 1982;Osman et al 2011;He et al 2012;Yang et al 2016) as well as kinetic scales (e.g., Leamon et al 1998;Sahraoui et al 2009Sahraoui et al , 2010Sahraoui et al , 2013Parashar & Matthaeus 2016).…”