Share Email Print

Proceedings Paper

Performance of the Southern African Large Telescope (SALT) High Resolution Spectrograph (HRS)
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

The Southern African Large Telescope (SALT) High Resolution Spectrograph (HRS) is a fibre-fed R4 échelle spectrograph employing a white pupil design with red and blue channels for wavelength coverage from 370–890nm. The instrument has four modes, each with object and sky fibres: Low (R~15000), Medium (R~40000) and High Resolution (R~65000), as well as a High Stability mode for enhanced radial velocity precision at R~65000. The High Stability mode contains a fibre double-scrambler and offers optional simultaneous Th-Ar arc injection, or the inclusion of an iodine cell in the beam. The LR mode has unsliced 500μm fibres and makes provision for nod-and-shuffle for improved background subtraction. The MR mode also uses 500μm fibres, while the HR and HS fibres are 350μm. The latter three modes employ modified Bowen-Walraven image-slicers to subdivide each fibre into three slices. All but the High Stability bench is sealed within a vacuum tank, which itself is enclosed in an interlocking Styrostone enclosure, to insulate the spectrograph against temperature and atmospheric pressure variations. The Fibre Instrument Feed (FIF) couples the four pairs of fibres to the telescope focal plane and allows the selection of the appropriate fibre pair for a given mode, and adjustment of the fibre separation to optimally position the sky fibre. The HRS employs a photomultiplier tube for an exposure meter and has a dedicated auto-guider attached to the FIF. We report here on the commissioning results and overall instrument performance since achieving first light on 28 September 2013.

Paper Details

Date Published: 24 July 2014
PDF: 14 pages
Proc. SPIE 9147, Ground-based and Airborne Instrumentation for Astronomy V, 91476T (24 July 2014); doi: 10.1117/12.2055635
Show Author Affiliations
Lisa A. Crause, South African Astronomical Observatory (South Africa)
Ray M. Sharples, Durham Univ. (United Kingdom)
David G. Bramall, Durham Univ. (United Kingdom)
Jürgen Schmoll, Durham Univ. (United Kingdom)
Paul Clark, Durham Univ. (United Kingdom)
Eddy J. Younger, Durham Univ. (United Kingdom)
Luke M. G. Tyas, SALT Foundation (South Africa)
Sean G. Ryan, Univ. of Hertfordshire (United Kingdom)
Janus D. Brink, SALT Foundation (South Africa)
Ockert J. Strydom, SALT Foundation (South Africa)
David A. H. Buckley, SALT Foundation (South Africa)
Martin Wilkinson, SALT Foundation (South Africa)
Steven M. Crawford, Southern African Large Telescope (South Africa)
Éric Depagne, SALT Foundation (South Africa)

Published in SPIE Proceedings Vol. 9147:
Ground-based and Airborne Instrumentation for Astronomy V
Suzanne K. Ramsay; Ian S. McLean; Hideki Takami, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?