*Special Seminar* Polarization in spectral lines: a window into the physics of the solar atmosphere

Event Dates: 

Tuesday, April 17, 2018 - 4:00pm

CTQM Seminar Type: 

  • Related Seminar Series

Speaker Name(s): 

Ivan Millic

Speaker Affiliation(s): 

Max Planck Institute for Solar System Research

Abstract, Event Details: 

The light that we receive from the Sun has passed through the solar atmosphere and undergone many scattering processes that leave their imprint on its spectral distribution and polarization state. These processes are influenced by the thermodynamic and magnetic properties of the plasma and thus the spectropolarimetric observations in spectral lines allow us to infer the temperature, velocity and magnetic field throughout the solar atmosphere.
This talk will focus on the Zeeman effect, scattering polarization and the Hanle effect, and how they contribute to form line polarization patterns. More specifically, the emphasis will be on spectral lines formed in non-local thermodynamic equilibrium conditions. Such lines typically probe the physical conditions in the upper layers of solar atmosphere, regions that are particularly interesting for their highly dynamic and magnetic nature. The diagnostic techniques, however, can be extended to a multitude of astrophysical objects, such as atmospheres of other stars and different types of accretion or circumstellar disks.
We will also discuss spectropolarimetric inversions, as the state-of-the-art tools used for the interpretation of the solar observations with high angular and spectral resolution. Finally, a brief outlook on the bright future of the field, especially in the light of Daniel K. Inouye Solar Telescope, will be presented.