PREDNASAJUCI / LECTURER :

Aaron W. Peat

(1) Center of Scientific Excellence – Solar and Stellar Activity,
University of Wrocław, Poland

NAZOV / TITLE :

Working Towards the Reconstruction of a Cool Post Flare Loop Observed with IRIS in Mg II h&k

ABSTRAKT / ABSTRACT :

We employ a 2D cylindrical NLTE (i.e. departure from local thermodynamic equilibrium) complete
redistribution radiative transfer (RT) code to reproduce the line profiles of a cool post flare
loop observed by the Interface Region Imaging Spectrograph (IRIS) in Mg II h&k on 22 June 2015.
The orientation and observing angle of the loop, as well as the local incident radiation, are
taken into account when initializing the RT code. This is of extreme importance for producing
the velocity field relative to the solar surface to properly model Doppler dimming and
brightening in the structure.

The IRIS data are first radiometrically calibrated and then point-spread function deconvolved
through a fifty-iteration Richardson–Lucy deconvolution to remove artefacts from nearby spatial
pixels. An implementation of the Levenberg–Marquardt algorithm is then used to minimise the
least-squares distance between the model and observation to produce a best fit. From this, we
aim to recover the thermodynamic properties of the loop, which will allow for its reconstruction.