A dual-beam spectrograph design for transient follow-up with SALT
Abstract
We present a low-resolution spectrograph design for the Southern African Large Telescope (SALT) primarily aimed at efficient identification spectroscopy of transients. The design extends the existing Robert-Stobie Spectrograph (RSS) by adding a new simultaneous red channel for wide visible wavelength coverage (360 nm to 900 nm). The design delivers R ~800 in the blue channel using the existing RSS optics and R ~2000 at a peak end-to-end instrument efficiency of 44% via the new red channel. We describe the instrument's requirements, optical design and expected performance. Synergies with existing RSS functionality are explored that will allow dual-beam multi-object and future integral field unit spectroscopy.
- Publication:
-
Ground-based and Airborne Instrumentation for Astronomy VIII
- Pub Date:
- December 2020
- DOI:
- 10.1117/12.2560996
- Bibcode:
- 2020SPIE11447E..68B