Thesis Defense by Svetlana Shkolyar on April 21st
Svetlana Shkolyar, online space studies master’s student, will defend her thesis:
When: Thursday, April 21st at 12:30 pm
Where: Ryan Hall, Room 111
Title: Intrinsic Sunspot Rotations and Their Potential Association with Solar Energetic Events
Sunspots provide insight into the thermal and dynamic interaction between convection and magnetic fields, and their rotation rates provide important information about their evolution as well as that of other solar events, such as solar flares. The focus of this work was to perform a similar analysis to Brown et al. (2003a) to study intrinsic rotation of sunspots and to determine if there is a correlation between sunspot rotation rates and the emergence of solar flares. Solar surface images in white light filters previously taken with the USAF/AFRL/NSO ISOON telescope at the National Solar Observatory on October 27-29, 2003 were used. After performing data reduction techniques on the images, the sunspots of interest were uncurled around their center to track their horizontal motion through time by stacking time-slice strips of images adjacently and tracking feature (i.e., penumbral fibrils) movement. These motions were tracked by analyzing the slopes of the movement of features at fixed radii of a sunspot pair of Active Region (AR) 10486 in white light from October 29, 2003. The right spot had an average penumbral clockwise rotation rate of 0.58°/hr. The left spot had an average penumbral counterclockwise rotation rate of 0.96°/hr. The study found an ambiguous correlation between X-class and C-class flares and intrinsic sunspot rotations, but no correlation between M-class flares and rotations. Other observations about the sunspots’ movement, complex influences on their intrinsic rotation, and limitations of the study are also discussed.