Multi-Line Spectro-Polarimetry of Stellar Magnetic Fields Using Principal Components Analysis
- Author(s)
- Meir Semel, D. E. Rees, Julio C. Ramirez Velez, Martin Stift, Francesco Leone
- Abstract
Zeeman-Doppler-Imaging (ZDI) is a technique for the diagnosis of stellar magnetic fields from observations of circularly polarized light, based on the weak-field approximation.
This approach has proved adequate in numerous studies of the magnetic fields of solar-type stars. To improve the signal-to-noise ratio, one can add the contributions of different lines to the polarization signature. However, this multi-line extension has been limited by a number of assumptions (e.g., the weak-field approximation). Here we present a novel approach. We created a database of synthetic polarized spectra for different combinations of magnetic-field intensities and orientations. Principal Components Analysis was used to compress the database, so that only few Principal Components are needed to represent all the calculated spectra.
- Organisation(s)
- Department of Astrophysics
- External organisation(s)
- Université Paris VII - Paris-Diderot, Université de recherche Paris Sciences et Lettres, Università degli Studi di Catania
- Pages
- 355
- Publication date
- 2006
- Austrian Fields of Science 2012
- 1030 Physics, Astronomy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/89ba1891-da4a-4a09-88ba-4a6ecd5cba5b