Speaker
Description
First Name: Daniel
Last Name: Verscharen
Email Address: d.verscharen@ucl.ac.uk
Affiliation: University College London
All Authors: Daniel Verscharen, Jingting Liu, Christopher Owen, and Georgios Nicolaou
Abstract: Electrons are a subsonic plasma species in the solar wind. Their kinetic behaviour is - to a much greater extent than the proton behaviour - the result of an interplay between global properties of the Sun-heliosphere system and local plasma processes. The global properties of the heliosphere include the interplanetary electrostatic potential, the large-scale interplanetary magnetic field, and the density profile of the plasma. The local plasma processes include collisions, wave-particle interactions, and turbulence. Through this interplay, the electron distribution function develops interesting kinetic features that are observable in situ with Solar Orbiter's SWA/EAS. The change in the overall collisionality of the electrons from the corona to the solar wind plays a key role for the definition of the relevant kinetic processes depending on distance from the Sun. In addition to a collision-dominated quasi-Maxwellian core, the distribution exhibits suprathermal populations in the form of the strahl and halo components as well as cut-offs due to loss effects in the interplanetary potential. We discuss the processes that shape the electron distribution in the solar wind, the interaction of electrons with local structures such as turbulence, waves, and magnetic holes, and the impacts of these structures on the global electron transport in the heliosphere.