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Australian Human Resources Institute Diversity Awards 2013 Finalist

U.C.L. Echelle Spectrograph (UCLES)

AAT Instrument



In Brief: UCLES is a cross-dispersed Echelle spectrograph located at the coudé focus offering high resolution combined with good wavelength coverage.

CYCLOPS2 is a cassegrain fibre-feed for UCLES. It is expected to be the default feed for most applications using the 79 l/mm echelle longwards of 4000A. Prospective users should consult the CYCLOPS2 status page and CYCLOPS2 web page at UNSW for more information.
Instrument Scientist: Gayandhi de Silva
See Instrument Scientist page for contact details. 
Manual: AAO UM-25.3 "The UCL Coudé Echelle Spectrographs", Stathakis et al, 2000. 
Other Info:

UCLES ThAr Atlas with the MITLL and EEV CCDs, Ryder, 2001.

AAO Precision Velocity Instrument for UCLES - Iodine Cell

For recently updated information see the UCLES Cookbook

A service programme is available for projects requiring <6 hrs.

Detector: Blue-sensitive EEV2 2K×4K (13.5 micron pixels) or red-sensitive MITLL3 2K×4K (15 micron pixels).
Focal Station: Mounted at Coudé with f/36 top end. 
Image Scale: 0.16 arcsec per spatial pixel with EEV2 and 0.18 arcsec per spatial pixel with MITLL3. All measurements taken without the focal modifier.
Spectral Resolution*: R = >100 000 possible with the EEV2, and <80 000 with the MITLL3. Note however that a 1 arcsec slit yields R~45,000.
Gratings: 31.6 lines/mm gives almost continuous wavelength coverage at bluer wavelengths, with short slit length (6-15 arcsec). 
79 lines/mm gives 2.5 times longer slit, but less complete wavelength coverage. 
Both gratings produce almost identical dispersion and resolution.
Sensitivities: See the Signal-to-Noise Calculator.
*Spectral Resolution R measured as &lambda/&delta&lambda, where &delta&lambda = FWHM unresolved line, usually 2 pixels.

Gayandhi De Silva, AAT Technical Secretary, aatts -@- aao.gov.au