Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-26T04:57:04.839Z Has data issue: false hasContentIssue false
  • English
  • Français

Zeeman Doppler Imaging

Published online by Cambridge University Press:  12 April 2016

M. Semel
M. Semel*
Affiliation:
Dasop-Ura326, Observatoire de Paris-Meudon, 92195 Meudon, France

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Stellar rotation maps the surface of a star into its line spectrum and gives a dimension to a point on the star - the Doppler dimension. This is of great importance for the detection of Zeeman polarization especially in certain cases. Typically a magnetic configuration will exhibit both polarities, thus the polarization signals of oposite signs may superpose and cancel. The Doppler coordinate will be in general different for parts of the stars having different polarities and therefore the polarization signals will also appear at different wavelengths and will not cancel. Moreover, the time variations plus the Doppler coordinate constitutes two variables that may allow the reconstruction of two dimensional map of the magnetic field over the star surface.

Attention will be given to the set-up that allows spectropolarimetry with high spectral resolution and high S/N ratio. The use of cross dispersion spectrographs allows one to observe several tens of spectral lines. The method of adding signals to increase S/N ratio will be indicated.

Type
5. Miscellaneous Methods
Information
International Astronomical Union Colloquium , Volume 149: Tridimensional Optical Spectroscopic Methods in Astrophysics , 1995 , pp. 340 - 349
Copyright
Copyright © Astronomical Society of the Pacific 1995

References

Semel, M. 1967, Ann.d’Ap., Tome 30 No 3, 513 Google Scholar
Semel, M., 1989, A&A 225, 456. (paper I).Google Scholar
Donati, J.-F., Semel, M. Rees, D.E., Taylor, K., Robinson, R.D., 1990, A&A 232, L1 Google Scholar
Brown, S.F., Donati, J.-F., Rees, D.E., Semel, M., 1991 A&A 250, 463 Google Scholar
Donati, J.-F. et al., 1992, A&A 265, 682.Google Scholar
Semel, M., Donati, J.-F. and Rees, D.E., 1993, A&A 278, 231 (paper III).Google Scholar