GNOSIS: an OH suppression unit for near-infrared spectrographs

S. C. Ellis, J. Bland-Hawthorn, J. S. Lawrence, J. Bryant, R. Haynes, A. Horton, S. Lee, S. Leon-Saval, Hans Gerd Löhmannsröben, J. Mladenoff, J. O'Byrne, W. Rambold, M. Roth, C. Trinh

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

18 Citations (Scopus)
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GNOSIS is an OH suppression unit to be used in conjunction with existing spectrographs. The OH suppression is achieved using fibre Bragg gratings (FBGs), and will deliver the darkest near-infrared background of any ground-based instrument. Laboratory and on-sky tests demonstrate that FBGs can suppress OH lines by 30dB whilst maintaing > 90% throughput between the lines, resulting in a ≈ 4 mag decrease in the background. In the first implementation GNOSIS will feed IRIS2 on the AAT. It will consist of a seven element lenslet array, covering ≈ 1.4″ on the sky, and will suppress the 103 brightest OH lines between 1.47 and 1.70 μm. Future upgrades will include J-band suppression and implementation on an 8m telescope.

Original languageEnglish
Title of host publicationGround-Based and Airborne Instrumentation for Astronomy III
EditorsIan S. McLean, Suzanne K. Ramsay, Hideki Takami
Place of PublicationBellingham, WA
Number of pages10
ISBN (Print)9780819482259
Publication statusPublished - 2010
EventGround-Based and Airborne Instrumentation for Astronomy III - San Diego, CA, United States
Duration: 27 Jun 20102 Jul 2010

Publication series

NameProceedings of SPIE
ISSN (Print)0277-786X


OtherGround-Based and Airborne Instrumentation for Astronomy III
Country/TerritoryUnited States
CitySan Diego, CA

Bibliographical note

Copyright 2010 Society of Photo Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.


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