Atmospheres of CP stars: magnetic field effects

Autor(en)

Denis Victorovich Shulyak, Gennady G. Valyavin

Abstrakt

The paper presents results of numerical modelling of magnetic field effects in atmospheres of CP stars. The calculations were carried out with the use of LLMODELS stellar model atmosphere code which incorporates detail description of atomic line absorption. First we investigate the influence of anomalous Zeeman splitting and polarized radiative transfer on model structures, energy distribution, synthetic photometric indices and hydrogen line profiles compared to non-magnetic reference models. As a next step, we model the magnetic pressure effects resulting from the interaction between the global poloidal magnetic field of a star and microscopic currents in its atmosphere. The Lorentz force appeared may noticeably affect the hydrostatic structure of the atmosphere and influence the formation of pressure-sensitive spectral lines. The results of such a modelling are compared with the recent observations of A0p star ? Aur which spectra show noticeable variations of H-line profiles with rotation phase that is interpreted in the framework of the model atmosphere analysis accounting for the Lorentz force effects. The results obtained may be considered as new evidences for the presence of non-zero electric currents in the atmospheres of early-type magnetic stars.

Organisation(en)

Institut für Astrophysik

Externe Organisation(en)

Korea Astronomy and Space Science Institute

Seiten

357-374

Anzahl der Seiten

18

Publikationsdatum

2007

ÖFOS 2012

103003 Astronomie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/02dc8985-63d6-47a0-8e23-b67b03b799d0