Comparison of observed (gray) and synthetic (black) Lyman lines and Hα line. The observed Lyman line profiles from each pixel in the SOHO/SUMER data and observed Hα profiles of the whole prominence are plotted. Synthetic data correspond to a randomly generated realization of Model2 with 40 threads and LOS velocities from interval of ⟨–10, 10⟩ km s^-1. Profiles from 83 positions along the foremost thread of the multi-thread model are plotted. The observed profiles are arbitrary shifted in wavelength to allow for an easy comparison.