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arXiv · 1612.03093

The W. M. Keck Observatory infrared vortex coronagraph and a first image of HIP79124 B

Eugene Serabyn·Elsa Huby·Keith Matthews·Dimitri Mawet·Olivier Absil·Bruno Femenia·Peter Wizinowich·Mikael Karlsson·Michael Bottom·Randy Campbell·Brunella Carlomagno·Denis Defrère·Christian Delacroix·Pontus Forsberg·Carlos Gomez Gonzalez·Serge Habraken·Aissa Jolivet·Kurt Liewer·Scott Lilley·Pierre Piron·Maddalena Reggiani·Jean Surdej·Hien Tran·Ernesto Vargas Catalan·Olivier Wertz
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Abstract

An optical vortex coronagraph has been implemented within the NIRC2 camera on the Keck II telescope and used to carry out on-sky tests and observations. The development of this new L'-band observational mode is described, and an initial demonstration of the new capability is presented: a resolved image of the low-mass companion to HIP79124, which had previously been detected by means of interferometry. With HIP79124 B at a projected separation of 186.5 mas, both the small inner working angle of the vortex coronagraph and the related imaging improvements were crucial in imaging this close companion directly. Due to higher Strehl ratios and more relaxed contrasts in L' band versus H band, this new coronagraphic capability will enable high-contrast small-angle observations of nearby young exoplanets and disks on a par with those of shorter-wavelength extreme adaptive optics coronagraphs.

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Eugene Serabyn, Elsa Huby, Keith Matthews, Dimitri Mawet, Olivier Absil, Bruno Femenia, Peter Wizinowich, Mikael Karlsson, Michael Bottom, Randy Campbell, Brunella Carlomagno, Denis Defrère, Christian Delacroix, Pontus Forsberg, Carlos Gomez Gonzalez, Serge Habraken, Aissa Jolivet, Kurt Liewer, Scott Lilley, Pierre Piron, Maddalena Reggiani, Jean Surdej, Hien Tran, Ernesto Vargas Catalan, Olivier Wertz. 2016-12-09. The W. M. Keck Observatory infrared vortex coronagraph and a first image of HIP79124 B. https://doi.org/10.3847/1538-3881%2F153%2F1%2F43

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