The impact of suprathermal electrons in solar wind macromodeling

Macro-modeling of the solar corona and solar wind seeks to describe the physical mechanisms that accelerate plasma particles to supersonic speeds and to explain their properties at various heliographic coordinates, increasingly sampled by space missions. Recent observational evidence provided by Parker Solar Probe on suprathermal electrons with Kappa-type velocity distributions at the origins of the solar wind has revived interest in deciphering kinetic effects and their consequences. We present new results from two complementary approaches of the solar wind, namely the kinetic-exospheric models and the HD/MHD fluid models with kinetic components. In this case, both approaches capture and quantify the effects of suprathermal electrons modeled with Kappa distributions, standard and regularized Kappa models. The latter have been introduced more recently for a physically and statistically consistent characterization of suprathermal populations and their consequences. Overestimations of the energy transferred directly or indirectly (e.g., through the ambipolar field created in the acceleration regions) to the solar wind by suprathermal electrons are thus prevented. One can consider for the first time those more energetic electrons, with strong suprathermal tails and associated with the source of energetic solar outflows, such as coronal mass ejections and bursts. Furthermore, such conditions cannot be ruled out as being conducive to the shaping of stellar winds in the astrospheres of stars with coronas much hotter than those of the solar corona.