Alexandra Z. Greenbaum, University of Michigan, Ann Arbor
Laurent Pueyo, Space Telescope Science Institute
Jean Baptiste Ruffio, Kavli Institute for Particle Astrophysics and Cosmology
Jason J. Wang, University of California, Berkeley
Robert J.De Rosa, University of California, Berkeley
Jonathan Aguilar, Johns Hopkins University
Julien Rameau, Institut de Recherche sur les Exoplanètes
Travis Barman, The University of Arizona
Christian Marois, National Research Council Canada
Mark S. Marley, NASA Ames Research Center
Quinn Konopacky, Center for Astrophysics & Space Sciences
Abhijith Rajan, School of Earth and Space Exploration
Bruce Macintosh, Kavli Institute for Particle Astrophysics and Cosmology
Megan Ansdell, University of California, Berkeley
Pauline Arriaga, University of California, Los Angeles
Vanessa P. Bailey, Jet Propulsion Laboratory
Joanna Bulger, National Institutes of Natural Sciences - National Astronomical Observatory of Japan
Adam S. Burrows, Princeton University
Jeffrey Chilcote, Kavli Institute for Particle Astrophysics and Cosmology
Tara Cotten, University of Georgia
Rene Doyon, Institut de Recherche sur les Exoplanètes
Gaspard Duchêne, University of California, Berkeley
Michael P. Fitzgerald, University of California, Los Angeles
Katherine B. Follette, Amherst College
Benjamin Gerard, National Research Council Canada
Stephen J. Goodsell, Gemini Observatory
James R. Graham, University of California, Berkeley
Pascale Hibon, Gemini ObservatorySouthern Operations Center
Li Wei Hung, University of California, Los Angeles
Patrick Ingraham, Large Synoptic Survey Telescope
Paul Kalas, University of California, Berkeley
James E. Larkin, University of California, Los Angeles
Kimberly Ward-Duong, Amherst CollegeFollow
et al, Various Institutions

Document Type


Publication Date


Publication Title

Astronomical Journal


We explore KLIP forward modeling spectral extraction on Gemini Planet Imager coronagraphic data of HR 8799, using PyKLIP, and show algorithm stability with varying KLIP parameters. We report new and re-reduced spectrophotometry of HR 8799 c, d, and e in the H and K bands. We discuss a strategy for choosing optimal KLIP PSF subtraction parameters by injecting simulated sources and recovering them over a range of parameters. The K1/K2 spectra for HR 8799 c and d are similar to previously published results from the same data set. We also present a K-band spectrum of HR 8799 e for the first time and show that our H-band spectra agree well with previously published spectra from the VLT/SPHERE instrument. We show that HR 8799 c and d show significant differences in their H and K spectra, but do not find any conclusive differences between d and e, nor between c and e, likely due to large error bars in the recovered spectrum of e. Compared to M-, L-, and T-type field brown dwarfs, all three planets are most consistent with mid- and late-L spectral types. All objects are consistent with low gravity, but a lack of standard spectra for low gravity limit the ability to fit the best spectral type. We discuss how dedicated modeling efforts can better fit HR 8799 planets' near-IR flux, as well as how differences between the properties of these planets can be further explored.


planets and satellites: gaseous planets, stars: individual (HR 8799)










© 2018. The American Astronomical Society.


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