Project description

Density Diagnostics in the Solar Corona

(supervisor: Youra Taroyan)

Nature of project: data analysis, software

Available to full-time physicists or joint students .

Best suited to students on these degree schemes:

• Physics
• Physics with Planetary and Space Physics
• Astrophysics

Project description and methodology

The optical radiation from the surface of the Sun or another star is what we see with our eyes. The optical emission in the solar atmosphere (corona) is many orders of magnitude less intense and can only be seen during an eclipse. The first observations of the corona date back to ancient times. The element helium was discovered in the solar corona in the 19th century. Current space missions have the capacity to observe the Sun in many different wavelengths. If we observe the Sun in X-rays, EUV or radio wavelengths, the corona appears bright and highly structured, while the surface becomes almost invisible.Current space borne instruments such as spectrometers can be used to measure intensities and velocities of the plasma at different heights and different temperatures. Density diagnostics are important for understanding the underlying physics of many processes in space plasmas. Such measurements can be done by using ratios of emission lines from particular ions that are sensitive to the electron density. Data from the EUV imaging spectrometer (EIS) onboard the Hinode satellite will be used to infer the plasma density in the lower solar atmosphere.      [edit]      [add Yr4]

Novelty, degree of difficulty and amount of assistance required

New data will be used. Instructions for the installation of EIS and CHIANTI, data download and analysis will be provided.      [edit]

Resources required

The project will require access to Solar Soft.      [edit]

Project milestones and deliverables (including timescale)

Initial literature for students

1. J. L. Culhane et al., The EUV Imaging Spectrometer for Hinode, Sol. Phys. 243, 3, 2007.
2. M. Aschwanden, Physics of the Solar Corona, Springer, 2006