Published by
EDP Sciences
EDP Sciences Journals List
Free access
Issue A&A
Volume 492, Number 3, December IV 2008
Page(s) 823 - 831
Section Stellar atmospheres
DOI http://dx.doi.org/10.1051/0004-6361:200810098



A&A 492, 823-831 (2008)
DOI: 10.1051/0004-6361:200810098

NLTE abundances of Mn in a sample of metal-poor stars

M. Bergemann and T. Gehren

Institute for Astronomy and Astrophysics, Ludwig-Maximilian University, Scheinerstr. 1, 81679 Munich, Germany
    e-mail: masha@rejoin.net

Received 30 April 2008 / Accepted 3 October 2008

Abstract
Aims. Following our solar work, we perform NLTE calculations of the Mn abundance for fourteen stars with [Fe/H] from 0 to –2.5, mainly to show how NLTE affects Mn abundances in cool stars of different metallicities.
Methods. The spectrum synthesis and Mn abundances are based on statistical equilibrium calculations using various estimates for the influence of hydrogen collisions.
Results. The NLTE abundances of Mn in all studied stars are systematically higher than the LTE abundances. At low metallicities, the NLTE abundance corrections may run up to 0.5–0.7 dex. Instead of a strong depletion of Mn relative to Fe in metal-poor stars as found by the other authors, we only find slightly subsolar values of [Mn/Fe] throughout the range of metallicities analyzed here.
Conclusions. The [Mn/Fe] trend in metal-poor stars is inconsistent with the predictions of galactic chemical evolution models, where Mn is less produced than Fe.


Key words: line: profiles -- line: formation -- stars: abundances -- nuclear reactions, nucleosynthesis, abundances



© ESO 2008

What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.
  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.