Anomalously bright UV lines of Fe II as a probe of gas condensations in the vicinity of hot stars
Lund Observatory, Lund University, PO Box 43, 22100 Lund, Sweden e-mail: Vladilen.Letokhov@astro.lu.se
2 Institute of Spectroscopy, Russian Academy of Sciences, Troitsk, Moscow region 142190, Russia
Corresponding author: S. Johansson, firstname.lastname@example.org
Accepted: 13 October 2003
Two UV lines of Fe II at 2507/2509 Å are extremely bright in spatially resolved HST/STIS spectra of dense gas condensations (the so called Weigelt blobs) close to the central star of η Carinae. The lines also appear unresolved in HST/FOS spectra of the star AE And. Under normal conditions the lines should hardly be observable. Based on recent studies of the formation of the 2507/2509 lines as part of a radiative cycle driven by HLyα pumping and including stimulated emission we propose the possibility of using them as a probe of non-homogeneities in gas condensations located outside hot, massive stars.
Key words: atomic processes / line: formation / radiation mechanisms: non-thermal / stars: individual: η Car, AE And
© ESO, 2003