First light of the Gemini Planet Imager
Abstract
The Gemini Planet Imager is a dedicated facility for directly imaging and spectroscopically characterizing extrasolar planets. It combines a very high-order adaptive optics system, a diffraction-suppressing coronagraph, and an integral field spectrograph with low spectral resolution but high spatial resolution. Every aspect of the Gemini Planet Imager has been tuned for maximum sensitivity to faint planets near bright stars. During first-light observations, we achieved an estimated H band Strehl ratio of 0.89 and a 5-σ contrast of 106 at 0.75 arcseconds and 105 at 0.35 arcseconds. Observations of Beta Pictoris clearly detect the planet, Beta Pictoris b, in a single 60-s exposure with minimal postprocessing. Beta Pictoris b is observed at a separation of 434 ± 6 milliarcseconds (mas) and position angle 211.8 ± 0.5°. Fitting the Keplerian orbit of Beta Pic b using the new position together with previous astrometry gives a factor of 3 improvement in most parameters over previous solutions. The planet orbits at a semimajor axis of <mml:math id="i5"><mml:mrow><mml:msubsup><mml:mrow><mml:mn>9.0</mml:mn></mml:mrow><mml:mrow><mml:mo>-</mml:mo><mml:mn>0.4</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>0.8</mml:mn></mml:mrow></mml:msubsup><mml:mtext> </mml:mtext><mml:mi mathvariant="bold">AU</mml:mi></mml:mrow></mml:math> near the 3:2 resonance with the previously known 6-AU asteroidal belt and is aligned with the inner warped disk. The observations give a 4% probability of a transit of the planet in late 2017.
- Publication:
-
Proceedings of the National Academy of Science
- Pub Date:
- September 2014
- DOI:
- 10.1073/pnas.1304215111
- arXiv:
- arXiv:1403.7520
- Bibcode:
- 2014PNAS..11112661M
- Keywords:
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- Astrophysics - Earth and Planetary Astrophysics;
- Astrophysics - Instrumentation and Methods for Astrophysics
- E-Print:
- 9 pages, 5 figures, accepted for publication Proc. Natl. Acad. Sci