starlabs

Stellare Laboratorien: Hochpräzisionsatomphysik mit STIS

01/07/2017 to 30/06/2020

Stellar atmospheres are prime laboratories to determine atomic properties of highly ionized species. Since
reliable metal opacities are crucial ingredients of many astrophysical simulations, we propose to exploit STIS's
spectroscopic capabilities to obtain high-resolution, high-S/N spectra of three hot subdwarf stars that exhibit
extremely high iron-group (calcium to nickel) abundances and, thus, are ideal objects to identify even weak
spectral lines of these species. The precise spectral analysis by advanced non-LTE model-atmosphere
techniques allows to determine photospheric properties accurately and subsequently derive relative weighted
oscillator strengths of iron-group lines. This will establish an important benchmark test for available atomic-line
lists of iron-group elements for ionization stages III to VI.