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Royal Greenwich Observatory (RGO) Spectrograph

AAT Instrument. RGO is a decommissioned instrument and is no longer offered or supported at the AAT. The following information is provided for historical completeness.

In Brief: The RGO Spectrograph is a general purpose optical spectrograph, covering 3100-11000Å. The 25cm camera can be used for long-slit spectroscopy, time series observations and spectropolarimetry. The 82cm camera has been superseded by UCLES for most applications, but is useful when small spatial pixels are needed (e.g. spectroastrometry).
Instrument Scientist: No Instrument Scientist at present. Contact Head of Astronomy for information.
Manual: AAO UM-2.4 "The RGO Spectrograph Manual" by R. A. Stathakis and H. M. Johnston, 2002.

"The Medium Dispersion Cu Ar Arc Atlas" by C. G. Tinney, 1995, available online as a gzip'd Postscript file. Other (hardcopy only) related manuals are; AAO UM-24.2 "Spectropolarimetry at the AAT" by J. Hough & J. Bailey, 1994; and AAO UM 4 and 4a, Arc Atlases for CuAr and FeAr.
Other Info: Information on the different gratings is available.
Wavelength centres and coverage for grating settings can be calculated using the RGOANG spectrograph facility

There is an entry in the Observer's Guide

Fact Sheet:

Detector: Portable CCD, usually the 2k x 4k EEV or MITLL CCDs.
Focal Station: Mounted at the Cassegrain focus with f/8 top end.
Image Scale: 0.43 arcsec per pixel with 25cm + EEV (unbinned)
Spectral Resolution*: A range of gratings offer R=850 (250B) to R=12 000 (1200l, 2nd order) at 6000Å with 1.7 arcsec slit. 
Filters: A range of neutral density and order sorting filters are available.
Sensitivities: Signal-to-Noise calculator
*Spectral Resolution R measured as lambda/delta_lambda, delta_lambda = FWHM unresolved line, usually 2 pixels.