Pierrard, VivianeAudoor, CharlineCharlineAudoor2025-05-142025-05-142025-05-142022https://hdl.handle.net/2078.2/27779Lately, two satellites providing very interesting measurements of the Sun have been launched: Parker Solar Probe (12 August 2018) and Solar Orbiter (10 February 2020). Parker Solar Probe travels closer to the surface of the Sun than any other spacecraft before and can provide information that helps to understand the mechanisms that take place in the solar corona. The solar wind is often studied with a kinetic exospheric model that assumes a certain velocity distribution function for each particle specie of the wind. These models give relatively good results and allow the explanation of various phenomena related to the solar wind by representing the electron distribution by a Kappa distribution associated with an index kappa . However, this distribution has limitations and kinetic models cannot compute all the macroscopic quantities for all the values of the kappa index. Recently, Scherer et al. (2017) introduced the regularized Kappa distribution resolving the critical limits and allowing a fluid description of the solar wind. The main objective of this work is the improvement of an exospheric model by modifying the electron distribution with the regularized Kappa distribution. In order to be able to analyse the results of the model adequately, this work will be divided into three parts. Since the model assumes a low altitude distribution, the first part will study the shape of the distributions at low distances measured by Parker Solar Probe. The second part will focus on the links that can be observed between solar wind parameters. The final part consists of the comparison of the model with in-situ observations from several satellites. This work illustrates the relevance of using a regularized Kappa distribution. It also shows the importance of considering suprathermal populations in the models. The exospheric model is a valid model, but by neglecting the Coulomb and wave-particle interactions, it can only reproduce accurately a limited number of moments.solar windKappa distributionexospheric modeltext::thesis::master thesisthesis:37521