Project description

The goal of this team is to advance our current understanding of the origin and evolution of different solar wind stream types, with particular reference to Alfvénic slow wind streams. This ISSI team will provide a comprehensive study of the Alfvénic slow wind in the inner heliosphere, using data from PSP, Solar Orbiter (SO), and observatories at Lagrangian point L1, and address the relative role of rapid field expansion and Alfvénic turbulence in accelerating the solar wind. The evolution of Alfvénicity in the inner heliosphere will be investigated using magnetic field and plasma measurements. Models (e.g Potential Field Source Surface model) will connect the sources at the sun to in situ measurements, and numerical simulations including expansion and gradient effects will be used to understand the different evolution of Alfvénic turbulence according to stream context. Source regions of the Alfvénic slow wind will be identified and characterized also using coronal composition derived from extreme-UV spectroscopy. The proposed team has an extensive expertise in solar-wind large scale structures and turbulence, in the key spacecraft missions involved, in UV spectroscopy, as well as in simulations of solar wind expansion and modeling of the solar magnetic field and solar-wind source regions.