List of Figures
A polarization modulator.
ISIS polarimeter schematic, with representative beam cross-sections and polarization ellipses.
ISIS polarization modulator and slit area.
Theoretical performance of superachromat halfwave. Actual as-made properties of ISIS superachromat can be measured in situ.
Planning aid to set slit vertical at mid-exposure; courtesy Robert Laing. The curve labels are declination values.
Scattered light causing false sky polarization. See text.
Linear polarization as a vector quantity. In each case, the complete circle denotes the rms error, the circular arcs are loci of constant degree of polarization. See text.
Actual performance of a halfwave plate similar to that of ISIS.
Wavelength-dependence of the apparent polarization angle. This is a direct consequence of specifying super-achromatism of the retardation; observations need to be corrected for this effect.
Optical elimination of sky polarization.
Dekker frame with Dekkers used during commissioning. Actual suite of Dekkers will be different from this. See text.
Tests on `unpolarized' star during commissioning (courtesy Dave Axon, Jim Hough). Lower panel is with calibration Polaroid in the beam; drop-off of degree of polarization at low pixel numbers is due to Polaroid failure.
Extract from Tinbergen 1979: zero-polarization stars.
Extract from Hsu and Breger 1982: standard stars for degree and angle of polarization, in 5 broad bands. Use with Bailey and Hough 1982, Whittet et al 1992.
Extract from Dolan and Tapia 1986: polarization variations in `standard stars'.
Extract from Bastien et al. 1988: polarization variations in `standard stars'.
Extract from Turnshek et al. 1990: HST polarization standards.
Extract from Turnshek et al. 1990: HST high-polarization extended objects.
Extract from Bailey and Hough 1982: standard stars for degree and angle of polarization, in 9 broad bands (U to K). Use with Whittet et al 1992, Hsu and Breger 1982.
Bibliography of polarization standards up to 1985.
Tue Oct 7 17:34:45 BST 1997