Sarah KovacGraduate Student NMSUAstronomy
I am currently a second-year graduate student working with Dr. R. T. James McAteer to investigate the sources of energy loss from solar coronal plasma. Most free energy that enters the sun’s atmosphere is subsequently released in the form of radiation or goes towards accelerating particles. These losses take the form of radiative and conductive losses, supplemented by the sudden release of energy in solar flares and coronal mass ejections (CMEs). We estimate the energy lost in both mechanisms by looking at differential emission measures (DEMs). This provides a thermal understanding of plasma that is used to study both plasma heating and cooling. The result of applying this approach to a particular active region will be a sequence of estimates of the energy in the coronal field and energy flux into or out of the corona. The actual instantaneous coronal energy is not well known, so we compare different estimates of changes in this energy. By expanding to multiple regions on the Sun, this provides new insight into how much energy is emitted from the solar corona. With this analysis, we will characterize the distribution of time delays between free energy being introduced to the corona, stored in the corona, and eventually released into the heliosphere.
As an undergraduate, I worked with Dr. Matthew Penn at the National Solar Observatory studying the fast solar wind. I was a lead student for the Citizen Continental America Telescopic Eclipse Experiment (Citizen CATE) and have been working on the project since 2015. This project aimed to capture 90 consecutive minutes of totality footage during the 21 August 2017 total solar eclipse using hundreds of volunteers across the country, from middle schoolers to amateur astronomers. I traveled to Indonesia in 2016 to observe a total solar eclipse, collect data, and test equipment and procedures in preparation for the 2017 eclipse. As a CATE Master Trainer, I was responsible for training volunteers and giving them feedback on practice data leading up to the eclipse. This experiment was a resounding success, with nearly 90% coverage across the United States. We are currently deriving new scientific results about the dynamics of the solar corona, particularly the solar wind. You can view our preliminary movie on our website.
Penn, M. J.; Baer, R.; Bosh, R.; Garrison, D.; Gelderman, R.; Hare, H.; Isberner, F.; Jensen, L.; Kovac, S.; McKay, M.; Mitchell, A.; Pierce, M.; Thompson, P.; Ursache, A.; Varsik, J.; Walter, D.; Watson, Z.; Young, D.; Citizen CATE Team 2017 Publications of the Astronomical Society of Pacific, 129, 971.