1.1 What are the source regions of the solar wind and heliospheric magnetic field?

• 1.1.1 Source regions of the fast solar wind
  • 1.1.1.1 Low FIP fast wind origins
  • 1.1.1.2 Origin of the small-scale X-ray and UV jets in polar coronal holes
• 1.1.2 Source regions of the slow solar wind
  • 1.1.2.1 Does slow wind originate from the over-expanded edges of coronal holes?
  • 1.1.2.2 Does slow and intermediate solar wind originate from coronal loops outside of coronal holes?
  • 1.1.2.3 Abundance of minor ions as a function of height in the corona as indicator of slow or fast wind
  • 1.1.2.4 Study of density fluctuations in the extended corona as a function of the outflow velocity of the solar wind while evolving in the heliosphere
  • 1.1.2.5 Structure and evolution of streamers
  • 1.1.2.6 Disentangle the spatial and temporal variability of the slow wind
  • 1.1.2.7 Trace streamer blobs and other structures through the outer corona and the heliosphere.
  • 1.1.2.8 Determine the velocity, acceleration profile and the mass of the transient slow wind flows
• 1.1.3 Source regions of the heliospheric magnetic field
  • 1.1.3.1 Full characterization of photospheric magnetic fields and fine structures
  • 1.1.3.2 How does the Sun's magnetic field link into space?
    • 1.1.3.2.1 How does the Sun's magnetic field change over time?
    • 1.1.3.2.2 How is the heliospheric current sheet (HCS) related to coronal structure?
    • 1.1.3.2.3 How does the heliospheric magnetic field disconnect from the Sun?
  • 1.1.3.3 What is the distribution of the open magnetic flux?
• 1.1.4 Transverse themes
  • 1.1.4.1 Reconnection
    • 1.1.4.1.1 Interchange reconnection between open and closed field lines and its role in slow wind generation
    • 1.1.4.1.2 Identify coronal reconnection sites by measuring impulsive event material
    • 1.1.4.1.3 Identify reconnection exhausts in the solar wind
    • 1.1.4.1.4 Current sheets inferred by determining the magnetic field geometries at local chromospheric heating sites
    • 1.1.4.1.5 Identify and characterise the solar wind reconnection physics in current sheets with thickness down to the ion scales and smaller
    • 1.1.4.1.6 Photospheric reconnection
    • 1.1.4.1.7 Electron acceleration in coronal reconnection regions
    • 1.1.4.1.8 Formation of flux ropes/CMEs via magnetic reconnection in the corona

In general:

◦       Determine the properties of the coronal plasma sources and their evolution during the wind acceleration from the photosphere to the corona.

◦       Identify the physical processes responsible for the evolution of the boundaries between wind types (shocks, shears, reconnection).

◦       Track the spatial evolution of the interfaces between fast, intermediate, and slow solar wind regimes at the solar surface and in the inner and extended corona.

◦       Determine the relative roles of coronal source effects and interplanetary processing in the appearance of the heliospheric plasma at 1 AU (radial evolution).

◦       Characterise turbulence/fluctuations and link to processes at work in source regions.

◦       Measure the variability of the solar wind outflow velocity mapped over the full outer corona through the solar cycle.