What is the origin and development of solar wind mesoscale structures?

Solar wind originating from different source regions on the Sun has distinct plasma parameters. Together with the solar rotation and the wind’s outward expansion, this leads to formation of the large-scale solar wind structures such as high-speed streams and stream interaction regions. At 1 AU, these structures typically have characteristic timescales around one day or more and can be preserved over large radial distances. In contrast, smaller-scale structures are more dynamic, reflecting the complex interplay of temporal variability in the source regions and changes, occurring during propagation of the solar wind through the heliosphere. Understanding all the competing processes that may act within large-scale solar wind structures remains incomplete. The unique combination of current missions—including the Parker Solar Probe (close to the Sun), Solar Orbiter (en route to Earth), and the WIND, ACE, and MMS spacecraft (near Earth)—offers an opportunity to track and characterize the evolution of solar wind parcels as they travel from the Sun to Earth. The main aim of the thesis will therefore be to study changes of plasma within large-scale solar wind structures across the inner heliosphere.

Literature:

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6. Journal papers upon recommendation of supervisor