The Gemini High-Resolution Optical SpecTrograph (GHOST) bench spectrograph optical design

Gemini High-Resolution Optical SpecTrograph (GHOST) is a fiber-fed spectrograph being developed for the Gemini telescope. GHOST is a white pupil échelle spectrograph with high efficiency and a broad continuous wavelength coverage (363-1000nm) with R>50,000 in two-object mode and >75,000 in single-object mode. The design incorporates a novel zero-Petzval sum white pupil relay to eliminate grating aberrations at the cross-dispersers. Cameras are based on non-achromatic designs with tilted detectors to eliminate the need for exotic glasses. This paper outlines the optical design of the bench-mounted spectrograph and the predicted spectrograph resolution and efficiency for the spectrograph.