Open AccessManganese abundances in mercury‐‐manganese stars
Author(s) -
Jomaron C. M.,
Dworetsky M. M.,
Allen C. S.
Publication year - 1999
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.1999.02252.x
Subject(s) - stars , manganese , physics , hyperfine structure , astrophysics , spectral line , abundance (ecology) , atomic physics , astronomy , chemistry , organic chemistry , fishery , biology
ABSTRACT We use exact curve‐of‐growth analysis and spectral synthesis to deduce the abundance of Mn from high signal‐to‐noise ratio visible‐region echelle spectra of selected Mn i and Mn II lines in 24 HgMn stars. The results are compared with the Mn abundances derived from UV resonance lines by Smith & Dworetsky. We find excellent agreement for several unblended Mn lines and confirm the temperature dependence of the Mn abundance found by Smith & Dworetsky. The Mn II lines at λλ 4206 and 4326 are much stronger than one would predict from the mean Mn abundances. The lack of agreement is greatest for stars with the strongest Mn II lines. Using ad hoc multicomponent fits to the profiles of sharp‐lined stars, we show that most of the discrepancies can be explained by hyperfine structure that desaturates the lines, with full widths of the order of 0.06‐‐0.09 Å.