Issue |
Astron. Astrophys. Suppl. Ser.
Volume 119, Number 1, October I 1996
|
|
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Page(s) | 171 - 176 | |
DOI | https://doi.org/10.1051/aas:1996235 | |
Published online | 15 October 1996 |
On the use of Bowen compensators for polarimetry
Universitäts-Sternwarte, Geismarlandstr. 11, D-37083 Göttingen, Germany
Send offprint request to: M. Koschinsky
Received:
16
January
1996
Accepted:
9
February
1996
For high precision polarimetry it is very desirable to
observe with a telescope that is free of instrumental
polarization. Yet it is often inevitable to introduce optical
devices which generate crosstalk between the Stokes
components and the V component due to phase retardations upon
reflection at mirror surfaces. We show that Bowen compensators
are well suited to compensate for these phase changes. They
consist of 2 rotatable
phase retarder plates, and
it can be shown that they act on polarized light either by a
rotation of the axes of the polarization ellipse followed by a
prescribed, desired phase change or by a phase change followed
by rotation of the ellipse. We present applications of Bowen
compensators in the Gregory Coudé Telescope at the
Observatorio del Teide/Tenerife.
Key words: instrumentation: polarimeters / techniques: polarimetric
© European Southern Observatory (ESO), 1996