260 citations · 1.1k across the 14 of their papers we have counts for
14 papers
A non-LTE study of neutral and singly-ionized iron line spectra in 1D models of the Sun and selected late-type stars
L. Mashonkina, T. Gehren, J. -R. Shi +2
A comprehensive model atom for Fe with more than 3000 energy levels is presented. As a test and first application of this model atom, Fe abundances are determined for the Sun and f…
Fe I/Fe II ionization equilibrium in cool stars: NLTE versus LTE
Lyudmila Mashonkina, Thomas Gehren, Jianrong Shi +2
Non-local thermodynamic equilibrium (NLTE) line formation for neutral and singly-ionized iron is considered through a range of stellar parameters characteristic of cool stars. A co…
Fe-peak element abundances in disk and halo stars
Maria Bergemann, Thomas Gehren
At present none of Galactic chemical evolution (GCE) models provides a self-consistent description of observed trends for all iron-peak elements with metallicity simultaneously. Th…
NLTE analysis of Co I/Co II lines in spectra of cool stars with new laboratory hyperfine splitting constants
M. Bergemann, J. C. Pickering, T. Gehren
We investigate the statistical equilibrium of Co in the atmospheres of cool stars, and the influence of NLTE and HFS (hyperfine splitting) on the formation of Co lines and abundanc…
Statistical equilibrium of silicon in the atmospheres of metal-poor stars
J. R. Shi, T. Gehren, L. Mashonkina +1
Aims. The statistical equilibrium of neutral and ionized silicon in the atmospheres of metal-poor stars is discussed. Non-local thermodynamic equilibrium effects are investigated a…
Statistical equilibrium of silicon in the solar atmosphere
J. R. Shi, T. Gehren, K. Butler +2
The statistical equilibrium of neutral and ionised silicon in the solar photosphere is investigated. Line formation is discussed and the solar silicon abundance determined. High-re…