NOAO > Library > NOAO Preprint Series > Preprint 889
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NOAO > Library > NOAO Preprint Series > Preprint 889 |
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Author(s): Keller, C. U.
Title: Instrumentation for Astrophysical
Spectropolarimetry
Abstract:
Astronomical spectropolarimetry is performed from the X-ray to the
radio regimes of the electromagnetic spectrum. The following chapter
deals with instruments and their components that are used in the
wavelength range from 300 nm to 20 µm. After introducing the
terminology and formalisms that are used in the context of the
astronomical spectropolarimeters, I discuss the most widely used
optical components. These include crystal and sheet polarizers,
fixed monochromatic, and achromatic retarders, and variable retarders
such as liquid crystals and photoelastic modulators. Since
polarimetric measurements are often limited by systematic errors
rather than statistical errors due to photon noise, I deal with these
instrumentally induced errors in detail. Among these errors, I discuss
instrumental polarization of various kinds and chromatic and angle
of incidence errors of optical components. I close with a few
examples of successful, modern night-time and solar spectropolarimeters.
Date Received:
February 06, 2001
Publication Info:
Proc. of the XII Canary Islands Winter School of Astrophysics, p. 303-354
Telescopes:
None
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NOAO > Library > NOAO Preprint Series > Preprint 889 |
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