288 citations · 467 across the 6 of their papers we have counts for
6 papers
The shock-patterned solar chromosphere in the light of ALMA
S. Wedemeyer-Boehm, H. -G. Ludwig, M. Steffen +2
Recent three-dimensional radiation hydrodynamic simulations by Wedemeyer et al. (2004) suggest that the solar chromosphere is highly structured in space and time on scales of only…
Numerical simulation of the three-dimensional structure and dynamics of the non-magnetic solar chromosphere
Sven Wedemeyer, Bernd Freytag, Matthias Steffen +2
Three-dimensional numerical simulations with CO5BOLD, a new radiation hydrodynamics code, result in a dynamic, thermally bifurcated model of the non-magnetic chromosphere of the qu…
Line formation in convective stellar atmospheres. I. Granulation corrections for solar photospheric abundances
M. Steffen, H. Holweger
In an effort to estimate the largely unknown effects of photospheric temperature fluctuations on spectroscopic abundance determinations, we have studied the problem of LTE line for…
Photospheric Abundances: Problems, Updates, Implications
H. Holweger
Current problems encountered in the spectroscopic determination of photospheric abundances are outlined and exemplified in a reevaluation of C, N, O, Ne, Mg, Si, and Fe, taking eff…
Dusty and dust-free A stars
Marc Hempel, Hartmut Holweger, Inga Kamp
We present preliminary results of our search for circumstellar absorption features in the Ca K lines based on high S/N observations obtained with the ESO CAT/CES system.
Dust and Gas around lambda Bootis Stars
I. Kamp, H. Holweger
High-resolution spectra of lambda Bootis stars reveal the presence of circumstellar gas for example in the Ca K line. The example of the normal A star beta Pictoris shows, that the…