Heavy Ion Signatures in Different Structures in the Solar Wind
The solar wind is a plasma stream released from the solar corona. Heavy ions, with atomic numbers greater than two, make up a small fraction of the solar wind but provide valuable insights into their source regions. Their elemental abundance and ionic charge states remain unchanged as they travel from the corona to Earth, where they are measured by ACE instruments. Different solar wind types and structures likely originate from distinct regions, undergoing unique heating and acceleration processes. Thus, heavy ion signatures help diagnose source conditions. CMEs are large solar eruptions containing plasma from multiple sources. This thesis introduces a multipopulation approach to identifying distinct Fe ion populations within CMEs and analyzing their source conditions. Typically, CMEs contain three to four Fe populations, sometimes including a very hot (~6 MK) component. The presence of this hot population and another close to the typical solar wind suggests a non-thermal equilibrium state in their source regions. FRs are twisted magnetic structures in the solar wind, spanning scales from 10⁻³ to 10⁻¹ AU. Their origins were compared to the surrounding solar wind, with evidence indicating that most FRs share similar source regions with the nearby plasma. This suggests FRs are unlikely to be interplanetary counterparts of small-scale coronal eruptions. To analyze solar wind parameter relationships, this thesis developed a tool incorporating timescales, intrinsic lags, and both linear and non-linear correlations. It identified over 100 short periods where Fe and O charge states exhibit an anticorrelation, in contrast to their usual long-term positive correlation. These structures, likely associated with stream boundaries, suggest that coronal conditions at different heights may exhibit opposite trends, reinforcing the "non-thermal equilibrium" conclusion from earlier findings.
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