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Title: Discovery of a wide planetary-mass companion to the young M3 star GU PSC

Abstract

We present the discovery of a comoving planetary-mass companion ∼42'' (∼2000 AU) from a young M3 star, GU Psc, a likely member of the young AB Doradus Moving Group (ABDMG). The companion was first identified via its distinctively red i – z color (>3.5) through a survey made with Gemini-S/GMOS. Follow-up Canada-France-Hawaii Telescope/WIRCam near-infrared (NIR) imaging, Gemini-N/GNIRS NIR spectroscopy and Wide-field Infrared Survey Explorer photometry indicate a spectral type of T3.5 ± 1 and reveal signs of low gravity which we attribute to youth. Keck/Adaptive Optics NIR observations did not resolve the companion as a binary. A comparison with atmosphere models indicates T {sub eff} = 1000-1100 K and log g = 4.5-5.0. Based on evolution models, this temperature corresponds to a mass of 9-13 M {sub Jup} for the age of ABDMG (70-130 Myr). The relatively well-constrained age of this companion and its very large angular separation to its host star will allow its thorough characterization and will make it a valuable comparison for planetary-mass companions that will be uncovered by forthcoming planet-finder instruments such as Gemini Planet Imager and SPHERE 9.

Authors:
; ; ; ; ; ; ;  [1];  [2];  [3]; ;  [4]; ;  [5]
  1. Département de physique and Observatoire du Mont-Mégantic, Université de Montréal, Montréal H3C 3J7 (Canada)
  2. Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)
  3. Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)
  4. Centre de Recherche Astrophysique de Lyon, UMR 5574 CNRS, Université de Lyon, École Normale Supérieure de Lyon, 46 Allée d'Italie, F-69364 Lyon Cedex 07 (France)
  5. Infrared Processing and Analysis Center, MS 100-22, California Institute of Technology, Pasadena, CA 91125 (United States)
Publication Date:
OSTI Identifier:
22356892
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 787; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ATMOSPHERES; COLOR; COMPARATIVE EVALUATIONS; DETECTION; EVOLUTION; GRAVITATION; IMAGES; INFRARED SURVEYS; MASS; NEAR INFRARED RADIATION; OPTICS; PHOTOMETRY; PLANETS; SATELLITES; STARS; TELESCOPES

Citation Formats

Naud, Marie-Eve, Artigau, Étienne, Malo, Lison, Albert, Loïc, Doyon, René, Lafrenière, David, Gagné, Jonathan, Boucher, Anne, Saumon, Didier, Morley, Caroline V., Allard, France, Homeier, Derek, Beichman, Charles A., and Gelino, Christopher R., E-mail: naud@astro.umontreal.ca. Discovery of a wide planetary-mass companion to the young M3 star GU PSC. United States: N. p., 2014. Web. doi:10.1088/0004-637X/787/1/5.
Naud, Marie-Eve, Artigau, Étienne, Malo, Lison, Albert, Loïc, Doyon, René, Lafrenière, David, Gagné, Jonathan, Boucher, Anne, Saumon, Didier, Morley, Caroline V., Allard, France, Homeier, Derek, Beichman, Charles A., & Gelino, Christopher R., E-mail: naud@astro.umontreal.ca. Discovery of a wide planetary-mass companion to the young M3 star GU PSC. United States. doi:10.1088/0004-637X/787/1/5.
Naud, Marie-Eve, Artigau, Étienne, Malo, Lison, Albert, Loïc, Doyon, René, Lafrenière, David, Gagné, Jonathan, Boucher, Anne, Saumon, Didier, Morley, Caroline V., Allard, France, Homeier, Derek, Beichman, Charles A., and Gelino, Christopher R., E-mail: naud@astro.umontreal.ca. Tue . "Discovery of a wide planetary-mass companion to the young M3 star GU PSC". United States. doi:10.1088/0004-637X/787/1/5.
@article{osti_22356892,
title = {Discovery of a wide planetary-mass companion to the young M3 star GU PSC},
author = {Naud, Marie-Eve and Artigau, Étienne and Malo, Lison and Albert, Loïc and Doyon, René and Lafrenière, David and Gagné, Jonathan and Boucher, Anne and Saumon, Didier and Morley, Caroline V. and Allard, France and Homeier, Derek and Beichman, Charles A. and Gelino, Christopher R., E-mail: naud@astro.umontreal.ca},
abstractNote = {We present the discovery of a comoving planetary-mass companion ∼42'' (∼2000 AU) from a young M3 star, GU Psc, a likely member of the young AB Doradus Moving Group (ABDMG). The companion was first identified via its distinctively red i – z color (>3.5) through a survey made with Gemini-S/GMOS. Follow-up Canada-France-Hawaii Telescope/WIRCam near-infrared (NIR) imaging, Gemini-N/GNIRS NIR spectroscopy and Wide-field Infrared Survey Explorer photometry indicate a spectral type of T3.5 ± 1 and reveal signs of low gravity which we attribute to youth. Keck/Adaptive Optics NIR observations did not resolve the companion as a binary. A comparison with atmosphere models indicates T {sub eff} = 1000-1100 K and log g = 4.5-5.0. Based on evolution models, this temperature corresponds to a mass of 9-13 M {sub Jup} for the age of ABDMG (70-130 Myr). The relatively well-constrained age of this companion and its very large angular separation to its host star will allow its thorough characterization and will make it a valuable comparison for planetary-mass companions that will be uncovered by forthcoming planet-finder instruments such as Gemini Planet Imager and SPHERE 9.},
doi = {10.1088/0004-637X/787/1/5},
journal = {Astrophysical Journal},
number = 1,
volume = 787,
place = {United States},
year = {Tue May 20 00:00:00 EDT 2014},
month = {Tue May 20 00:00:00 EDT 2014}
}
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