Published June 6, 2016 | Version v1
Poster Open

CFBDSIR2149-0403, a puzzling free-floating planet candidate: low-gravity or high-metallicity ?

Authors/Creators

  • 1. Institut UTINAM, CNRS UMR6213, Univ. Bourgogne Franche-Comté, OSU THETA Franche-Comté-Bourgogne
  • 2. Univ. Grenoble Alpes, CNRS, IPAG
  • 3. The University of Texas at Austin, Department of Astronomy
  • 4. Carnegie Institution of Washington DTM
  • 5. IfA, University of Hawai'i
  • 6. Institut de Recherche sur les Exoplanètes, Université de Montréal
  • 7. Univ. Lyon, ENS de Lyon, Univ. Lyon1, CNRS, Centre de Recherche Astrophysique de Lyon UMR 5574
  • 8. Zentrum für Astronomie der Universität Heidelberg

Contributors

  • 1. Uppsala University, University of North Georgia

Description

Discoveries of very massive planets, on one hand, and very low mass isolated brown dwarfs, on the other hand, show

that the brown dwarf and the planetary mass ranges widely overlap. When these low mass brown dwarfs are close and

bright enough to be observed in spectroscopy, their atmospheres are much easier to study than similar exoplanets that lie

nearby their very bright host stars.

When we identified CFBDSIR214947.2-040308.9 (Delorme et al 2012), it appeared as a good candidate member of the

AB-Doradus young moving group and together with the low gravity features in its spectrum made it a unique T type

isolated planetary-mass object.

In order to ascertain its nature and determine its physical properties, we conducted additional observations: X-Shooter

spectroscopy from 0.8 to 2.3 μm, mid-IR photometry with the Spitzer Space Telescope, as well as a parallax follow-up

over 2 years.

While the spectral information confirm the low gravity or high metallicity of the atmosphere, the new kinematics safely rule

out membership to any known young moving group. Therefore this object is a peculiar late T dwarf, perhaps a young free

floating planet or an older, heavier brown dwarf with supersolar metallicity.

Notes

Poster #240

Files

posterCS19.pdf

Files (602.6 kB)

Name Size Download all
md5:c1299ca3d80b11136252596d69597696
602.6 kB Preview Download

Additional details

Related works

Is previous version of
10.1051/0004-6361/201629633 (DOI)

References

  • Allard et al 2013, Memorie della Societa Astronomica Italiana, v.84, No. 4, p.1053
  • Baraffe et al 2003, A&A, 402, 701
  • Delorme et al 2012, A&A, 548, A26
  • Faherty et al 2014, ApJ, 790, 90
  • Gagné J. et al 2014, ApJ, 783,121
  • McLean et al 2003, ApJ, 593, 561