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arXiv · 1309.6357

Electric Field Conjugation with the Project 1640 coronagraph

Eric Cady·Christoph Baranec·Charles Beichman·Douglas Brenner·Rick Burruss·Justin Crepp·Richard Dekany·David Hale·Lynne Hillenbrand·Sasha Hinkley·E. Robert Ligon·Thomas Lockhart·Ben R. Oppenheimer·Ian Parry·Laurent Pueyo·Emily Rice·Lewis C. Roberts, Jr.·Jennifer Roberts·Michael Shao·Anand Sivaramakrishnan·Remi Soummer·Hong Tang·Tuan Truong·Gautam Vasisht·Fred Vescelus·J. Kent Wallace·Chengxing Zhai·Neil Zimmerman
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Abstract

The Project 1640 instrument on the 200-inch Hale telescope at Palomar Observatory is a coronagraphic instrument with an integral field spectrograph at the back end, designed to find young, self-luminous planets around nearby stars. To reach the necessary contrast for this, the PALM-3000 adaptive optics system corrects for fast atmospheric speckles, while CAL, a phase-shifting interferometer in a Mach-Zehnder configuration, measures the quasistatic components of the complex electric field in the pupil plane following the coronagraphic stop. Two additional sensors measure and control low-order modes. These field measurements may then be combined with a system model and data taken separately using a white-light source internal to the AO system to correct for both phase and amplitude aberrations. Here, we discuss and demonstrate the procedure to maintain a half-plane dark hole in the image plane while the spectrograph is taking data, including initial on-sky performance.

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Eric Cady, Christoph Baranec, Charles Beichman, Douglas Brenner, Rick Burruss, Justin Crepp, Richard Dekany, David Hale, Lynne Hillenbrand, Sasha Hinkley, E. Robert Ligon, Thomas Lockhart, Ben R. Oppenheimer, Ian Parry, Laurent Pueyo, Emily Rice, Lewis C. Roberts, Jr., Jennifer Roberts, Michael Shao, Anand Sivaramakrishnan, Remi Soummer, Hong Tang, Tuan Truong, Gautam Vasisht, Fred Vescelus, J. Kent Wallace, Chengxing Zhai, Neil Zimmerman. 2013-09-24. Electric Field Conjugation with the Project 1640 coronagraph. https://doi.org/10.1117/12.2024635

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