2010/04/01 by O. Kochukhov, Kochukhov, O., E. Khomenko +1
Engineering · Physics and Astronomy · #Astronomical Observations and Instrumentation #Astronomy and Astrophysical Research #FOS: Physical sciences #Solar and Stellar Astrophysics (astro-ph.SR) #Stellar, planetary, and galactic studies #astro-ph.SR
paper · pdf · doi:10.48550/arxiv.1004.0139
4 pages, 4 figures, Proceedings of the HELAS IV International Conference submitted to Astronomische Nachrichten
arxiv created 2010/04/01 · openalex publication_date 2010/04/01 · arxiv updated 2015/03/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Time-resolved spectroscopic observations of rapidly oscillating Ap (roAp) stars show a complex picture of propagating magneto-acoustic pulsation waves, with amplitude and phase strongly changing as a function of atmospheric height. We have recently conducted numerical, non-linear MHD simulations to get an insight into the complex atmospheric dynamics of magnetic pulsators. Here we use the resulting time-dependent atmospheric structure and velocity field to predict line profile variations for roAp stars. These calculations use realistic atmospheric structure, account for vertical chemical stratification and treat the line formation in pulsating stellar atmosphere without relying on the simplistic single-layer approximation universally adopted for non-radial pulsators. The new theoretical calculations provide an essential tool for interpreting the puzzling complexity of the spectroscopic pulsations in roAp stars.