Description
Using 2D Mgɪɪ h&k solar prominence modelling, we aim to understand the formation of complex line profiles and how these are seen by the Interface Region Imaging Spectrograph (IRIS). Additionally, we see how the properties of these simulated observations are interpreted by traditional 1D prominence modelling. A cylindrical NLTE (i.e. departures from local thermodynamic equilibrium) 2D complete redistribution (CRD) code was used to generate a set of cylindrical prominence strands, which we stacked behind each other to produce complex line profiles. Then, with the use of the point spread functions (PSFs) of IRIS, we were able to predict how IRIS would observe these line profiles. We then used the 1D NLTE code PROM to find the properties recovered by traditional 1D prominence modelling.
Velocities of magnitude lower than 10 km/s are sufficient to produce asymmetries in the Mgɪɪ h&k lines. However, convolution of these with the PSFs of IRIS obscures this detail and returns standard looking single peaks. By increasing the velocities by a factor of three, we recover asymmetric profiles even after this convolution. The properties recovered through traditional 1D modelling appear adequate at first, but the best fit profiles do not satisfactorily represent the simulated data. This is likely due to the large line width of the simulated profiles.
