Gabriele Kalus
Bursar
Abundance and isotopic anomalies of thallium in the atmosphere of the HgMn star chi Lupi
Author
Summary, in English
We announce the detection of two fully resolved hyperfine components of the intercombination line of Tl II (Z = 81) at 1908.6 Angstrom in the ultraviolet spectrum of the sharp-lined, nonmagnetic, chemically peculiar star chi Lupi (BB.5pHgMn + A2 Vm). The wavelengths and profiles of these absorption lines strongly suggest that they arise from the heaviest isotope, Tl-205. The echelle observations were obtained with the Hubble Space Telescope Goddard High Resolution Spectrograph (HST/GHRS). Spectrum synthesis fits to the line profiles yield a logarithmic overabundance of thallium, relative to the solar system abundance, of +3.8 dex. We believe this to be the first detection of thallium in a star other than the Sun. It is also the first time hyperfine structure has been resolved in the satellite ultraviolet spectrum of an astrophysical source. The large overabundance and the presence of only the heaviest isotope of the element continue the pattern observed previously in chi Lup for platinum (Z = 78), gold (Z = 79), and mercury (Z = 80).
Department/s
- Lund Observatory - Has been reorganised
- Department of Physics
Publishing year
1996
Language
English
Pages
937-942
Publication/Series
Astrophysical Journal
Volume
462
Issue
2
Document type
Journal article
Publisher
American Astronomical Society
Topic
- Astronomy, Astrophysics and Cosmology
Keywords
- abundances
- individual (chi Lupi)
- stars
- peculiar
Status
Published
ISBN/ISSN/Other
- ISSN: 0004-637X