24 September 2012 The AAO's Gemini High-Resolution Optical SpecTrograph (GHOST) concept
Author Affiliations +
The Gemini High-Resolution Optical SpecTrograph (GHOST) will fill an important gap in the current suite of Gemini instruments. We will describe the Australian Astronomical Observatory (AAO)-led concept for GHOST, which consists of a multi-object, compact, high-efficiency, fixed-format, fiber-fed design. The spectrograph itself is a four-arm variant of the asymmetric white-pupil echelle Kiwispec spectrograph, Kiwisped, produced by Industrial Research Ltd. This spectrograph has an R4 grating and a 100mm pupil, and separate cross-disperser and camera optics for each of the four arms, carefully optimized for their respective wavelength ranges. We feed this spectrograph with a miniature lensletbased IFU that sub-samples the seeing disk of a single object into 7 hexagonal sub-images, reformatting this into a slit with a second set of double microlenses at the spectrograph entrance with relatively little loss due to focal-ratio degradation. This reformatting enables high spectral resolution from a compact design that fits well within the relatively tight GHOST budget. We will describe our baseline 2-object R~50,000 design with full wavelength coverage from the ultraviolet to the silicon cutoff, as well as the high-resolution single-object R~75,000 mode.
© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Michael J. Ireland, Stuart Barnes, David Cochrane, Matthew Colless, Peter Connor, Anthony Horton, Steve Gibson, Jon Lawrence, Sarah Martell, Peter McGregor, Tom Nicolle, Kathryn Nield, David Orr, J. Gordon Robertson, Stuart Ryder, Andrew Sheinis, Greg Smith, Nick Staszak, Julia Tims, Pascal Xavier, Peter Young, Jessica Zheng, "The AAO's Gemini High-Resolution Optical SpecTrograph (GHOST) concept", Proc. SPIE 8446, Ground-based and Airborne Instrumentation for Astronomy IV, 844629 (24 September 2012); doi: 10.1117/12.925746; https://doi.org/10.1117/12.925746


Back to Top