Improved estimate of the magnetic field in a prominence

We present new results on the inversion of spectropolarimetric data of the He I D3 line in a prominence. These data were taken with the High Altitude Observatory Stokes II polarimeter on 1980 August 5. Full Stokes profiles in I, Q, U, and V were recorded at 13 locations of a prominence at the northeast limb. This prominence erupted 3 hr later, giving rise to the day of year 218 Solar Maximum Mission coronal transient. The data were originally analyzed in a paper by Querfeld et al. Here we analyze the data using the new inversion algorithm proposed by Lopez Ariste & Casini based on pattern recognition techniques. This method employs full Stokes profiles, and in tests on synthetic data, it proved to be much more precise than previous diagnostic procedures. When applied to the Stokes data of the prominence under study, it gives magnetic field strengths at least 2 times larger than previous estimates.