AM Seminar: Topology of the solar coronal magnetic field

Speaker Name: 
Marc L. DeRosa
Speaker Title: 
Staff Physicist
Speaker Organization: 
Lockheed Martin Solar and Astrophysics Laboratory
Start Time: 
Monday, January 6, 2020 - 4:00pm
End Time: 
Monday, January 6, 2020 - 5:00pm
Location: 
Baskin Engineering 372
Organizer: 
Abhishek Halder

Abstract:

The magnetic field of the solar corona is observed to continually evolve in response to ever-changing magnetic structures on the photospheric surface that are produced by the turbulent solar dynamo. The corona's continuous, quasi-steady evolution occurring most of the time is occasionally interrupted by solar flare events, which represent the very rapid conversion of built-up magnetic stresses into light, heat, and kinetic energy. Many, but not all, flares are associated with the eruption and ejection of coronal material into interplanetary space, causing variable near-Earth conditions collectively known as space weather. In this work, we explore the question of why some flares are eruptive and others are not, by analyzing the topology of the coronal magnetic fields (as determined from models), with the aim of identifying to what degree the large-scale structure of the global coronal magnetic field plays a role in determining the eruptivity of magnetically active regions. Coronal magnetic fields are shown to possess a rich spectrum of topological features that we are only beginning to understand.

Bio:

Dr. Marc L. DeRosa is currently a Staff Physicist at the Lockheed Martin Solar and Astrophysics Laboratory in Palo Alto, CA. He received his Ph.D. from the Astrophysical and Planetary Sciences Department at the University of Colorado, Boulder, in 2001. His research interests include using data and models to investigate the intricate dynamics of the sun, from the solar interior through the photosphere and into the corona. He additionally participates in the operation of both the Solar Optical Telescope on board the Hinode spacecraft as well as the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, both of which are NASA-sponsored missions that observe the sun from space.

Event Type: 
Event