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From Demonstration to Operation: High Contrast Imaging Tools at Keck Observatory
Charlotte E. Guthery  1@  , Jacques Delorme  1@  , Mike Bottom  2@  , Sam Walker  3@  , Maria Vincent  3@  , Rebecca Jensen-Clem  4@  , Maissa Salama  4@  , Vincent Chambouleyron  4@  , Jules Fowler  4@  , Maaike Van Kooten  5@  , James Wallace  6@  , Charlotte Bond  7@  , Sylvain Cetre  8, 9@  , Sam Ragland  1@  , Peter Wizinowich  1@  
1 : W.M. Keck Observatory
65-1120 Mamalahoa Hwy, Kamuela, HI 96743 -  United States
2 : Institute of Astronomy [Hilo]
640 North A'ohoku Place, Hilo, HI 96720, USA -  United States
3 : University of Hawai‘i [Mānoa]
1890 East-West Rd, Honolulu, HI 96822 -  United States
4 : University of California [Santa Cruz]
1156 High Street, Santa Cruz, Ca 95064 -  United States
5 : NRC Herzberg Astronomy and Astrophysics
5071 West Saanich Road, Victoria, BC, V9E 2E7 -  Canada
6 : Jet Propulsion Laboratory
4800 Oak Grove Drive, Pasadena, CA 91109-8099, USA -  United States
7 : Royal Observatory Edinburgh
Blackford Hill, EH9 3HJ -  United Kingdom
8 : Durham University
Stockton Road, Durham, UK -  United Kingdom
9 : Wakea Consulting
Wakea Consulting
Grenoble, Auvergne-Rhˆone-Alpes, France -  France

High contrast imaging (HCI) is limited in practice by uncorrected wavefront errors within traditional adaptive optics (AO). Keck observatory experiences roughly 130nm of unacoounted residual wavefront error even with well calibrated AO. Multiple HCI tools currently in development are presented, focused on minimizing these errors and improving contrast during typical observation nights: (1) Fast and Furious is a focal plane wavefront sensing algorithm shown to correct for large portions of non-common path aberrations between the NIRC2 science instrument and the primary Keck wavefront sensor (WFS). On sky demonstrations of an operational version of this algorithm show an increase in Strehl ratio up to 19% in a single run. (2) The Keck primary mirror phasing is known to degrade between routine segment exchanges. A Zernike wavefront sensor (ZWFS) is currently installed within the Keck Planet Imager and Characterizer (KPIC) to take passive measurements of the primary mirror to maintain the phasing. The detection of segment piston wavefront errors down to 50 nm with the ZWFS demonstrates the first step of maintaining phasing in parallel with science observations. (3) Operational speckle nulling algorithms are in test to minimize bright speckles during HCI. (4) As an addition to an upgraded real time controller, predictive wavefront control will be further developed to minimize errors due to large windspeeds and servo lag. These HCI demonstrations will be built as reliable, robust, and simple to control operational tools which will become available to greatly benefit observers.


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