Electric Field Conjugation with the Project 1640 coronagraph

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.

9 pages, 7 figures, in Proceedings of SPIE, 8864-19 (2013)

Cited by in corpus (9)

• DARKNESS: A Microwave Kinetic Inductance Detector Integral Field Spectrograph for High-Contrast Astronomy
• Direct Spectrum of the Benchmark T dwarf HD 19467 B
• High-speed imaging and wavefront sensing with an infrared avalanche photodiode array
• Lessons for WFIRST CGI from ground-based high-contrast systems
• Closed-loop focal plane wavefront control with the SCExAO instrument
• Project 1640 Observations of Brown Dwarf GJ 758 B: Near-Infrared Spectrum and Atmospheric Modeling
• A deep search for planets in the inner 15 au around Vega
• PULSE: The Palomar Ultraviolet Laser for the Study of Exoplanets
• SLM-based Digital Adaptive Coronagraphy: Current Status and Capabilities