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Estimate Low and High Order Wavefront Using P1640 Calibrator MeasurementsP1640 high contrast imaging system on the Palomar 200 inch Telescope consists of an apodized-pupil Lyot coronagraph, the PALM-3000 adaptive optics (P3K-AO), and P1640 Calibrator (CAL). Science images are recorded by an integral field spectrograph covering J-H bands for detecting and characterizing stellar companions. With aberrations from atmosphere corrected by the P3K-AO, instrument performance is limited mainly by the quasi-static speckles due to noncommon path wavefront aberrations for the light to propagate to the P3K-AO wavefront sensor and to the coronagraph mask. The non-common path wavefront aberrations are sensed by CAL, which measures the post-coronagraph E-field using interferometry, and can be effectively corrected by offsetting the P3K-AO deformable mirror target position accordingly. Previously, we have demonstrated using CAL measurements to correct high order wavefront aberrations, which is directly connected to the static speckles in the image plane. Low order wavefront, on the other hand, usually of larger amplitudes, causes light to leak through the coronagraph making the whole image plane brighter. Knowledge error in low order wavefront aberrations can also affect the estimation of the high order wavefront. Even though, CAL is designed to sense efficiently high order wavefront aberrations, the low order wavefront front can be inferred with less sensitivity. Here, we describe our method for estimating both low and high order wavefront aberrations using CAL measurements by propagating the post-coronagraph E-field to a pupil before the coronagraph. We present the results from applying this method to both simulated and experiment data.
Document ID
20150008073
Acquisition Source
Jet Propulsion Laboratory
Document Type
Conference Paper
External Source(s)
Authors
Zhai, C.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Vasisht, G.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Shao, M.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Lockhart, T.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Cady, E.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Oppenheimer, B.
(American Museum of Natural History New York, NY, United States)
Burruss, R.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Roberts, J.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Beichman, C.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Brenner, D.
(American Museum of Natural History New York, NY, United States)
Crepp, J.
(Notre Dame Univ. Notre Dame, IN, United States)
Dekany, R.
(California Inst. of Tech. Pasadena, CA, United States)
Hillenbrand, L.
(California Inst. of Tech. Pasadena, CA, United States)
Hinkley, S.
(California Inst. of Tech. Pasadena, CA, United States)
Parry, I.
(Cambridge Univ. Cambridge, United Kingdom)
Pueyo, L.
(Johns Hopkins Univ. Baltimore, MD, United States)
Rice, E.
(American Museum of Natural History New York, NY, United States)
Roberts, L. C. Jr.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Sivaramakrishnan, A.
(Space Telescope Science Inst. Baltimore, MD, United States)
Soummer, R.
(Johns Hopkins Univ. Baltimore, MD, United States)
Tang, H.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Vescelus, F.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Wallace, K.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Zimmerman, N.
(Max-Planck-Inst. fuer Aeronomie Hanover, Germany)
Date Acquired
May 13, 2015
Publication Date
August 25, 2013
Subject Category
Astronomy
Meeting Information
Meeting: SPIE Optics and Photonics
Location: San Diego, CA
Country: United States
Start Date: August 25, 2013
End Date: August 29, 2013
Sponsors: International Society for Optical Engineering
Distribution Limits
Public
Copyright
Other
Keywords
aberrations
coronagraph
deformable mirror (DM)
Palomar

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