G191-B2B: accurate abundances for nitrogen, silicon, and iron from GHRS observations.
Koester, D.; Vauclair, G.; Ferlet, R.; Vidal-Madjar, A.; Lallement, R.; Lemoine, M.; Bertin, P.; Allard, N. F.
France, Germany
Abstract
We present a new abundance analysis from high resolution GHRS spectra for 3 heavy elements showing spectral lines that are almost certainly of photospheric origin. The derived values (number abundances relative to hydrogen are 4+/-1.5x10^-6^ for N, 3+/-1.5x10^-7^ for Si, and 3+/-1.5x10^-6^ for Fe. These abundances are more accurate than previous values derived from IUE observations and can be used to provide constraints on the remaining and so far not unambiguously identified absorption in the EUV.