Title:Magnetic Waves in Solar Coronal Loops|
Type of Project:Data analysis and numerical modeling
Skills/Interest Required: Interest in analysis of space-based observations and use of advanced modeling techniques. No advanced programming skills required.
Mentor:Aad van Ballegooijen and Yingna Su
The solar corona is heated to temperatures in excess of 1 million
degrees Kelvin. Extreme ultraviolet (EUV) and X-ray observations of
the corona show bright loops that are aligned with the magnetic
field. The precise mechanisms by which the corona is heated are not
yet understood, but magnetic fields are known to play an important
role. One possibility is that the heating is due to the dissipation of
so-called Alfven waves, a type of magnetic waves that travel along
magnetic field lines like waves on a string. The attached figure shows
results from a simulation of the dynamics of Alfven waves in coronal
loops. Specifically, the figure shows selected magnetic field lines
(a) in the lower atmosphere at one end of the loop, and (b) in the
loop itself. The actual loop length is much larger than its width;
image (b) is vertically compressed by a factor 50.
The intern will analyze EUV observations of coronal loops obtained
with the Atmospheric Imager Assembly (AIA) on the Solar Dynamics
Observatory (SDO) satellite, and search for evidence of Alfven waves
in the corona. He/she will learn about the physics of Alfven waves,
and will use an existing software program ("braid") to simulate the
dynamics of Alfven waves in coronal loops, as illustrated above.
The goal of this project is to determine whether coronal loops may be
heated by Alfven waves.
Figure: Braided Coronal Loops