skip to main content


Title: Point source polarimetry with the Gemini planet imager: Sensitivity characterization with T5.5 dwarf companion HD 19467 B

Detecting polarized light from self-luminous exoplanets has the potential to provide key information about rotation, surface gravity, cloud grain size, and cloud coverage. While field brown dwarfs with detected polarized emission are common, no exoplanet or substellar companion has yet been detected in polarized light. With the advent of high contrast imaging spectro-polarimeters such as GPI and SPHERE, such a detection may now be possible with careful treatment of instrumental polarization. In this paper, we present 28 minutes of H-band GPI polarimetric observations of the benchmark T5.5 companion HD 19467 B. We detect no polarization signal from the target, and place an upper limit on the degree of linear polarization of $${p}_{\mathrm{CL}99.73\%}\leqslant 2.4\%$$. In conclusion, we discuss our results in the context of T dwarf cloud models and photometric variability.
 [1] ; ORCiD logo [2] ; ORCiD logo [1] ;  [3] ;  [1] ; ORCiD logo [4] ;  [5] ; ORCiD logo [6] ; ORCiD logo [7] ;  [8] ; ORCiD logo [9] ; ORCiD logo [10] ; ORCiD logo [11] ; ORCiD logo [12] ; ORCiD logo [13]
  1. California Inst. of Technology (CalTech), Pasadena, CA (United States)
  2. Univ. of Toronto, Toronto, ON (Canada)
  3. Univ. of California, Berkeley, CA (United States)
  4. Stanford Univ., Palo Alto, CA (United States)
  5. Univ. of Exeter, Exeter (United Kingdom)
  6. Univ. of California, Santa Cruz, CA (United States)
  7. Space Telescope Science Institute, Baltimore, MD (United States)
  8. NASA Ames Research Center, Moffett Field, CA (United States)
  9. Univ. of California, Los Angeles, CA (United States)
  10. American Museum of Natural History, New York, NY (United States)
  11. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  12. Gemini Observatory, La Serena (Chile)
  13. SETI Institute, Mountain View, CA (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 1538-4357
Grant/Contract Number:
Accepted Manuscript
Journal Name:
The Astrophysical Journal (Online)
Additional Journal Information:
Journal Name: The Astrophysical Journal (Online); Journal Volume: 820; Journal Issue: 2; Journal ID: ISSN 1538-4357
Institute of Physics (IOP)
Research Org:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org:
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; brown dwarfs; stars: individual (HD 19467); techniques; high angular resolution; techniques: polarimetric
OSTI Identifier: