3 papers
astro-ph2005
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…
astro-ph1998
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.
astro-ph1998
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…