Numerical Analysis Seminars: Numerical sunspot studies in the chromosphere and upper convection zone
26 February 2016 14:00 in CM105
Sunspots have been popular since the dawn of modern astronomy when Galileo observed them using the first telescopes. They are used as marker for the solar dynamo and solar variability, have an influence on the solar atmosphere and solar wind, and play an important part in space weather prediction. Two numerical studies associated with sunspots will be presented, simulating the chromospheric resonator and magnetoconvection around the sunspot umbra. The resonator is situated in the chromosphere above the umbra and oscillates with a three-minute period. Its resonating cavity is formed by large temperature gradients at the photosphere and the transition region and its physics is dominated by the magnetic field. In contrast, magnetoconvection in the upper convection zone of the Sun is dominated by plasma flow. Simulations of convection around the umbral flux tube show the formation of a collar flow underneath the photosphere that plays a large part in the formation, maintenance and decay of the sunspot.
Contact David.Bourne@durham.ac.uk for more information