Abstract

Relationship between magnetic field and Mg II line profiles in a tornado-like prominence
Structure and Dynamics of Magnetic Fields in the Sun, Solar System and Beyond
Peter Levens
University of Glasgow
N. Labrosse (University of Glasgow), B. Schmieder (Observatoire de Paris, Meudon), A. Lopez Ariste (IRAP, Toulouse), L. Fletcher (University of Glasgow)
Coordinated observations of solar prominences can be a challenge to perform, and even more so to analyse.
During international campaigns in 2014 and 2015 we focused on studying tornado-like prominences with a combination of space-based satellites (IRIS, Hinode and SDO) and ground based telescopes (THEMIS, Meudon MSDP).
We measured the magnetic field strength and orientation in these tornado-like structures using the He I D3 line from THEMIS, and studied the prominence plasma behaviour at a range of temperatures using IRIS, Hinode and SDO.
With a robust 2D cross correlation method to co-align data from different instruments, we are able to probe plasma and magnetic properties in the prominence on a pixel-by-pixel basis, allowing for a complete analysis of conditions in the tornado.
We present data from 15 July 2014, wherein we show spectral analysis of the Mg II h and k lines from IRIS, line profile analysis of Hinode/EIS lines, and inversion results from THEMIS.
We also study the relationship between line profile shape and magnetic field for both the Mg II lines and lines observed by Hinode/EIS.
Differences between the observations in optically thick (Mg II, He II, Ca II) and optically thin coronal lines are also investigated.
Mg II profiles show a mixture of reversed and non-reversed profiles in the prominence, with the reversed profiles mostly occurring where the magnetic field is strongest, reaching between 20 and 50 G in some parts.
We measure an unambiguously horizontal magnetic field in these structures, parallel to the limb.

Schedule

16:30 - 18:00
16:48
Thursday
EX - C33 (150)

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