Prosiectau Ffiseg ar gyfer myfyrwyr bl.3 a bl.4

Disgrifiad prosiect

Mapping the velocity of flare coronal loops

(supervisor: David Kuridze)

Nature of project: data analysis, experimental

Available to students on full-time physics degree schemes or joint students.

Project description and methodology

Solar flares are rapid energy releases within active regions caused by the reconnection of the coronal magnetic field resulting in coronal plasma heating to temperatures beyond tens of millions of kelvins. On September 10 2017 Active Region (AR) 12673 produced one of the most powerful flare (X8.2-class) of solar cycle 24. The flare led to intense heating and evaporation of dense chromospheric plasma into the loop system. The chromospheric plasma underwent rapid cooling (condensation) and the coronal loops subsequently filled with cool plasma. A well-developed set of flaring coronal loops was observed 10 minutes after the flare peak showing strong downflows of condensed plasma from the loop apex toward the footpoints.

The aim of this project is to measure the line-of-sight (LOS) component of the downflowing plasma motions and produced 2D LOS velocity map (Dopplergram) of the flare loop arcade. The student will use high-resolution spectroscopic data from the Swedish 1-m Solar Telescope. The spectral line profiles will be used for calculation of a Doppler shifts to determine the plasma LOS velocity.

A successful project will develop beyond the above in one/some of the following directions:
The main way to develop this project further is to measure the plane of the sky (POS) component of the velocity and reconstruct 3D velocity map of the flare loop arcade.

When considering where to take your project, please bear in mind the time available. It is preferable to do fewer things well than to try many and not get conclusive results on any of them. However, sometimes it is useful to have a couple of strands of investigation in parallel to work on in case delays occur.

This project is only available as a Y3 project.

Please speak to David Kuridze (dak21) if you consider doing this project.

Initial literature for students:

  1. An Introduction to Modern Astrophysics, Bradley W Carroll, Dale A Ostlie (authors), Chapter: The Sun, page 332 - 341
  2. Kuridze, D., Mathioudakis, M., Morgan, H., et al. 2019, ApJ, The Astrophysical Journal, 874, 126
  3. Fletcher, L., Dennis, B. R., Hudson, H. S., et al. 2011, Space Science Reviews, 159, Issue 1-4, 19-106
  4. Uitenbroek, H., 2003, The Accuracy of the Center-of-Gravity Method for Measuring Velocity and Magnetic Field Strength in the Solar Photosphere, Astrophysical Journal, 592, 1225

Novelty, degree of difficulty and amount of assistance required

Fully processed imaging spectroscopy data and assistance how to analyse it will be provided. IDL training will be provided by the supervisor.

Project milestones and deliverables (including timescale)

milestoneto be completed by
The basics of spectroscopy (overview)end of October
Learning how to open/load the SST data in IDL and an develop the codeChristmas
Fitting the spectra using Gaussian functionend of February
Determine plasma LOS velocities. Easter