Please note that eDoc will be permanently shut down in the first quarter of 2021!      Home News About Us Contact Contributors Disclaimer Privacy Policy Help FAQ

Quick Search
My eDoc
Session History
Support Wiki
Direct access to
document ID:

          Institute: MPI für Astronomie     Collection: Publikationen_mpia     Display Documents

ID: 693385.0, MPI für Astronomie / Publikationen_mpia
Estimate low- and high-order wavefront using P1640 calibrator measurements
Authors:Zhai, C.; Vasisht, G.; Shao, M.; Lockhart, T.; Cady, E.; Oppenheimer, B.; Burruss, R.; Roberts, J.; Beichman, C.; Brenner, D.; Crepp, J.; Dekany, R.; Hillenbrand, L.; Hinkley, S.; Parry, I.; Pueyo, L.; Rice, E.; Roberts, L. C.; Sivaramakrishnan, A.; Soummer, R.; Tang, H.; Vescelus, F.; Wallace, K.; Zimmerman, N.
Date of Publication (YYYY-MM-DD):2013
Title of Proceedings:Techniques and Instrumentation for Detection of Exoplanets VI
Start Page:id. 88640L (9 pp)
Volume (in Series):8864
Name of Conference/Meeting:Techniques and Instrumentation for Detection of Exoplanets VI
Audience:Not Specified
Abstract / Description:P1640 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.
Comment of the Author/Creator:Date: 2013, September 1, 2013
External Publication Status:published
Document Type:Conference-Paper
Communicated by:N. N.
Affiliations:MPI für Astronomie
The scope and number of records on eDoc is subject to the collection policies defined by each institute - see "info" button in the collection browse view.