Gemini Planet Imager Coronagraph Testbed Results

Journal Article · Wed Dec 08 04:00:00 EST 2010 · Proceedings of SPIE - The International Society for Optical Engineering

DOI:https://doi.org/10.1117/12.858623· OSTI ID:1000738

Sivaranmakrishnan, A; Carr, G; Soummer, R; Oppenheimer, B R; Mey, J L; Brenner, D; Mandeville, C W; Graham, J R; Saddlemyer, L; Bauman, B; Carlotti, A; Pueyo, L; Tuthill, P G; Dorrer, C; Roberts, R; Greenbaum, A

The Gemini Planet Imager (GPI) is an extreme AO coronagraphic integral field unit YJHK spectrograph destined for first light on the 8m Gemini South telescope in 2011. GPI fields a 1500 channel AO system feeding an apodized pupil Lyot coronagraph, and a nIR non-common-path slow wavefront sensor. It targets detection and characterizion of relatively young (<2GYr), self luminous planets up to 10 million times as faint as their primary star. We present the coronagraph subsystem's in-lab performance, and describe the studies required to specify and fabricate the coronagraph. Coronagraphic pupil apodization is implemented with metallic half-tone screens on glass, and the focal plane occulters are deep reactive ion etched holes in optically polished silicon mirrors. Our JH testbed achieves H-band contrast below a million at separations above 5 resolution elements, without using an AO system. We present an overview of the coronagraphic masks and our testbed coronagraphic data. We also demonstrate the performance of an astrometric and photometric grid that enables coronagraphic astrometry relative to the primary star in every exposure, a proven technique that has yielded on-sky precision of the order of a milliarsecond.

• Research Organization: BROOKHAVEN NATIONAL LABORATORY (BNL)
• Sponsoring Organization: DOE - Office Of Science
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 1000738
• Report Number(s): BNL--94477-2010-JA; KC0401030
• Journal Information: Proceedings of SPIE - The International Society for Optical Engineering, Journal Name: Proceedings of SPIE - The International Society for Optical Engineering Vol. 7735; ISSN PSISDG; ISSN 0277-786X
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
79 ASTRONOMY AND ASTROPHYSICS
ACCURACY
ASTRONOMY
DETECTION
FEEDING
GLASS
MIRRORS
PERFORMANCE
PLANETS
RESOLUTION
SCREENS
SILICON
STARS
TARGETS
TELESCOPES