Abstract Details

Name: Wageesh Mishra
Affiliation: Max Planck Institute for Solar System Research, Germany
Conference ID: ASI2020_298
Title : Modeling the Thermodynamic Evolution of Coronal Mass Ejections
Authors and Co-Authors : Wageesh Mishra, Luca Teriaca, Yuming Wang, Yutian Chi, and Jie Zhang
Abstract Type : Oral
Abstract Category : Sun and the Solar System
Abstract : Several earlier studies, using remote sensing and in situ observations, have attempted to estimate the thermodynamic properties of Coronal Mass Ejections (CMEs) either very close to the Sun or at 1 AU. In our study, we attempt to understand the evolution of the internal state of CMEs during their heliospheric propagation. For this purpose, we use the flux rope internal state (FRIS) model which is constrained by the kinematics of the CMEs. The kinematics of the CME is estimated using the STEREO/SECCHI observations in combination with drag based model (DBM) of CME propagation. In our analysis, we have selected a few Earth-directed CMEs which are launched with different speeds into different solar wind conditions. We also attempt to compare the estimated thermodynamic properties of the CMEs from the FRIS model with the in situ observations of the CMEs taken at 1 AU. We focus on estimating the polytropic index of the CME plasma, heating/cooling rate, entropy changing rate, Lorentz force and thermal pressure force acting inside the CME. We outline the approximations made in our study of probing the internal state of the CME during its heliospheric evolution and discuss the possible causes of the observed discrepancies.