Zeeman Doppler imaging of stars with the AAT

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

5

Stars, Spectroscopy

Scientific paper

Zeeman Doppler Imaging (ZDI) is a recent technique for measuring magnetic fields on rapidly rotating, active stars. ZDI employs spectropolarimetry taken at different rotational phases, to derive information on the magnetic field distribution over the stellar surface. The Zeeman effect is used to identify the presence of a magnetic field, and variations in Doppler wavelength shifts across the rapidly rotating star allow fields to be resolved on different parts of the visible disc. Analysis of the spectra can be used to produce both thermal and surface magnetic images. ZDI requires very high S/N spectra to be acquired, within a time interval short compared to the stellar rotation period. As a result, a large aperture telescope is needed. Since an initial successful test in 1989, the 3.9m Anglo-Australian Telescope has been used to obtain ZDI spectra of active stars of different evolutionary stages. The observations have concentrated on the K subgiant in the RS CVn system HR 1099, to monitor changes on this bright and active star. With the advent in 1991 of ZDI spectropolarimetry with the AAT 'echelle spectrograph, it has become possible to co-add the polarisation signature from the many magnetically sensitive lines recorded simultaneously. As a result, stellar magnetic field detections of unprecedented quality have been obtained. The aims of this paper are to briefly outline the principles of ZDI, describe the instrumental setup at the AAT and present some preliminary results from recent observations.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Zeeman Doppler imaging of stars with the AAT does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Zeeman Doppler imaging of stars with the AAT, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Zeeman Doppler imaging of stars with the AAT will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1420667

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.