RHEA: the ultra-compact Replicable High-resolution Exoplanet and Asteroseismology spectrograph

Tobias Feger*, Carlos Bacigalupo, Timothy R. Bedding, Joao Bento, David Coutts, Michael Ireland, Quentin Parker, Aaron Rizzuto, Izabela Spaleniak

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference proceeding contributionpeer-review


We present the opto-mechanical design and the characterization of the Replicable High-resolution Exoplanet and Asteroseismology (RHEA) spectrograph. RHEA is an ultra-compact fiber-fed echelle spectrograph designed to be used at 0.2 0.4 m class robotic telescopes where long term dedicated projects are possible. The instrument will be primarily used for radial velocity (RV) studies of low to intermediate-mass giant stars for the purpose of searching for hot Jupiters and using asteroseismology to simultaneously measure the host star parameters and de-correlate stellar pulsations. The optical design comprises a double-pass (i.e. near Littrow) configuration with prism cross-disperser and single-mode fiber (SMF) input. The spectrograph has a resolving power of R>70,000 and operates at 430670 nm with minimum order separation of similar to 180 mu m. This separation allows a 1x6 photonic lantern integration at a later stage which is currently under development. The current design is built with the aim of creating an inexpensive and replicable unit. The spectrograph is optimised for long-baseline RV observations through careful temperature stabilisation and simultaneous wavelength calibration. As a further improvement the echelle grating is housed in a vacuum chamber to maintain pressure stability. The performance of the current prototype is currently being tested on a 0.4 m telescope at the Macquarie University Observatory.

Original languageEnglish
Title of host publicationGround-based and airborne instrumentation for astronomy V
EditorsSuzanne K. Ramsay, Ian S. McLean, Hideki Takami
Place of PublicationWashington, DC
Number of pages12
ISBN (Electronic)9780819496157
Publication statusPublished - 2014
Event5th Conference on Ground-Based and Airborne Instrumentation for Astronomy - Montreal, Canada
Duration: 22 Jun 201426 Jun 2014

Publication series

NameProceedings of SPIE
ISSN (Print)0277-786X


Conference5th Conference on Ground-Based and Airborne Instrumentation for Astronomy


  • single-mode spectrograph
  • high-resolution
  • vacuum chamber
  • exoplanets
  • asteroseismology

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