Description
We explored the impact that Doppler dimming and brightening effects from bulk motions of isolated structures have on the formation of Lyα, Hα, and Mgɪɪh line profiles. This study was carried out in the context of solar prominence physics, but will be applicable to different structures and/or in stellar contexts. We compared two regimes in which these effects manifest: when the prominence is moving radially away from the solar surface (radial case), and when the prominence is moving parallel to the solar surface (horizontal case). The latter of these has not been thoroughly investigated in recent decades. To do this, we analysed 13,332 sets of model profiles generated through the use of the 1D non-local thermodynamic equilibrium (NLTE) radiative transfer (RT) code Promweaver, built on the Lightweaver NLTE RT framework to mimic the behaviour and output of the 1D NLTE RT code PROM, with the addition of overlapping transitions and arbitrary bulk velocity fields. We found that the horizontal case can produce a much greater dimming or brightening effect than the radial case with velocities of similar magnitude. This implies that horizontal velocities need to be accounted for when attempting to do any sort of interpretation and/or forward modelling.
