Affordable Access

Access to the full text

Gemini Planet Imager Observational Calibrations VIII: Characterization and Role of Satellite Spots

  • Wang, Jason J.
  • Rajan, Abhijith
  • Graham, James R.
  • Savransky, Dmitry
  • Ingraham, Patrick J.
  • Ward-Duong, Kimberly
  • Patience, Jennifer
  • De Rosa, Robert J.
  • Bulger, Joanna
  • Sivaramakrishnan, Anand
  • Perrin, Marshall D.
  • Thomas, Sandrine J.
  • Sadakuni, Naru
  • Greenbaum, Alexandra Z.
  • Pueyo, Laurent
  • Marois, Christian
  • Oppenheimer, Ben R.
  • Paul Kalas
  • Cardwell, Andrew
  • Goodsell, Stephen
  • And 3 more
Publication Date
Jul 07, 2014
Submission Date
Jul 07, 2014
DOI: 10.1117/12.2055753
arXiv ID: 1407.2308
SETI Institute
External links


The Gemini Planet Imager (GPI) combines extreme adaptive optics, an integral field spectrograph, and a high performance coronagraph to directly image extrasolar planets in the near-infrared. Because the coronagraph blocks most of the light from the star, it prevents the properties of the host star from being measured directly. Instead, satellite spots, which are created by diffraction from a square grid in the pupil plane, can be used to locate the star and extract its spectrum. We describe the techniques implemented into the GPI Data Reduction Pipeline to measure the properties of the satellite spots and discuss the precision of the reconstructed astrometry and spectrophotometry of the occulted star. We find the astrometric precision of the satellite spots in an $H$-band datacube to be $0.05$ pixels and is best when individual satellite spots have a signal to noise ratio (SNR) of $> 20$. In regards to satellite spot spectrophotometry, we find that the total flux from the satellite spots is stable to $\sim 7\%$ and scales linearly with central star brightness and that the shape of the satellite spot spectrum varies on the $2\%$ level.

Report this publication


Seen <100 times