High-contrast imaging with Keck adaptive optics and OSIRIS

Abstract

While more than 200 extrasolar planets have been discovered using indirect techniques, the direct detection of this class of object has remained at the sensitivity limits of ground based observatories. The development of improved adaptive optics systems and high contrast instruments has increased the sensitivity to extrasolar planets. We present high contrast results from the OSIRIS infrared lenslet-based integral field spectrograph (IFS) operating behind the Keck II adaptive optics (AO) system. OSIRIS spatially samples the Keck PSF at the diffraction limit, while providing a spectral resolution of 3800 for each spaxel. The OSIRIS integral field sampling simultaneously monitors the PSF over a broad band (20%), and this sampling is used to identify and suppress speckle diffraction features. The high-contrast sensitivity of Keck II AO near-infrared IFS (OSIRIS) and near-infrared imager (NIRC2) are compared.