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2.7m Telescope
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Cassegrain f/17.7

Large Cass Spectrometer (LCS)

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Dr. Anita Cochran
(512) 471-1471

Large Cassegrain Spectrograph main page

A low-to-moderate-resolution spectrometer (R = 600-2,500) for faint object work available with TI1 and CC1 CCDs. Various gratings provide wavelength coverage from 0.3 to 1.1 microns. The LCS has long slit (150 arcsec) capability and CCD-based guiding and acquisition. Limiting magnitude mv = 20. The TI1 CCD has better QE at all wavelengths but suffers from severe fringing for wavelengths redward of 6,000 Å; thus for red work, CC1 is the better choice. Both chips can be used all the way to the atmospheric cutoff, but TI1 is better than CC1 in the blue.