Helioseismic observations of magnetohydrodynamics of the solar interior
Seminar Room 1, Newton Institute
Observations of the Sun's interior with the MDI instrument on board the SOHO spacecraft has provided tremendous amount of new information about basic physical MHD processes inside the Sun, formation of magnetic structures in the solar plasma and mechanisms of solar and stellar activity. In particular, the new results have revealed the deep structure of sunspots and associated complicated patterns of plasma flows, the dynamics of the emerging magnetic flux and formation of active regions, the supergranular structure and dynamics of the upper convection zone, as well as the global structures and circulation patterns in the deep interior, evolving with the activity cycle. In addition, first attempts are made to find the links between the internal dynamics and processes of magnetic energy release in the solar corona. Understanding of these results, often puzzling and counter-intuitive, represents a major challenge for MHD theories of astrophysical plasma.