Gemini Planet Imager Observational Calibrations III: Empirical   Measurement Methods and Applications of High-Resolution Microlens PSFs
  The newly commissioned Gemini Planet Imager (GPI) combines extreme adaptive optics, an advanced coronagraph, precision wavefront control and a lenslet-based integral field spectrograph (IFS) to measure the spectra of young extrasolar giant planets between 0.9-2.5 um. Each GPI detector image, when in spectral model, consists of ~37,000 microspectra which are under or critically sampled in the spatial direction. This paper demonstrates how to obtain high-resolution microlens PSFs and discusses their use in enhancing the wavelength calibration, flexure compensation and spectral extraction. This method is generally applicable to any lenslet-based integral field spectrograph including proposed future instrument concepts for space missions. 
Patrick Ingraham, Jean-Baptiste Ruffio, Marshall D. Perrin, Schuyler   G. Wolff, Zachary H. Draper, Jerome Maire, Franck Mar...
astro-ph.IM astro-ph.EP