Prominence parameters derived by 2D modelling from hydrogen Lyman series measured by SOHO/SUMER

We present SOHO/SUMER observations of a solar prominence in the hydrogen Lyman series lines and Lyman continuum and compare the line intensities with synthetic ones obtained using our 2D prominence modelling. The observations contain the Lyman-$alpha$ to Lyman-$5$ lines and Lyman continuum observed on 25 May 2005. Each line-profile is averaged along the slit. In order to derive the prominence parameters we used our 2D fine structure models of vertical threads in magnetohydrostatic (MHS) equilibrium. Such thread models have been described by Heinzel & Anzer (2001) and Heinzel, Anzer & Gunár (2005). Starting with a grid of 18 models constructed in the latter paper we found a model having the Lyman line profiles similar to observed ones. By varying the input model parameters (central temperature, boundary pressure, magnetic field, central column mass and turbulent velocity) we obtained synthetic line profiles which are in good agreement with the observed ones. In this way we are able to determine the structure of the magnetic dip and thermodynamical parameters in the observed prominence.