The CCD Imaging/Spectropolarimeter combines polarizing optics and a transmission-optics
spectrograph into a self-contained, portable, and extremely high-throughput
instrument. It was designed and constructed in 1990-91 by Gary Schmidt and
H.S. Stockman (STScI). The polarimeter section is a dual-beam design which
incorporates rotating achromatic waveplates and a full-aperture Wollaston
prism. The detector is a 1200x800 pixel Loral CCD with quantum efficiency
enhanced through UV-flooding and an antireflection coating of hafnium oxide.
With current gratings, spectral resolutions of 4-15A are available over a
range in useful spectral response of 3800-9000A. The detection of linear or
circular polarization at a level p < 0.05% is possible. In the
imaging mode, polarization maps can be obtained in filtered bandpasses at
the seeing limit over a field of view 51" square at the 2.3-m or 19" square
at the MMT. The polarimeter is a standalone instrument with a dedicated
CCD, camera controller, instrument computer, and comparison lamp system.
Optimized for an f/9 beam, CCD SPOL can be mounted directly on the
Steward Observatory 2.3-m telescope or the 6.5-m converted MMT, and has
been adapted for use at the 4-m Mayall telescope on Kitt Peak, the 74" Mt.
Stromlo reflector, the 1.9-m Perkins telescope at Lowell Observatory, and
the 1.51-m telescope atop Mt. Bigelow.
CCD SPOL is a PI (Private-Investigator) instrument, available for use through
arrangement and collaboration with Gary Schmidt and
Left: Total and circularly polarized flux spectra of the
150MG magnetic cataclysmic variable V884 Her. The bottom panel presents
calculated cyclotron polarization spectra for various angles to the magnetic
field direction. The polarization peak around 7300A is the cyclotron
fundamental - the first time this has been seen from a white dwarf. From Schmidt,
Ferrario, Wickramasinghe, & Smith (2001)
Right: Total and linearly polarized flux spectra of the highly polarized
2MASS QSO 2M151653+1900, showing a highly polarized spectrum in total flux
which lacks the narrow emission lines in scattered light. From Smith,
Schmidt, Hines, Cutri & Nelson (2000).
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This page created by Gary Schmidt (email@example.com).