JpGU-AGU Joint Meeting 2017

Presentation information

[EE] Oral

A (Atmospheric and Hydrospheric Sciences) » A-AS Atmospheric Sciences, Meteorology & Atmospheric Environment

[A-AS01] [EE] 3D Cloud Modeling as a Tool for 3D Radiative Transfer, and Conversely

Sun. May 21, 2017 10:45 AM - 12:15 PM 304 (International Conference Hall 3F)

convener:Thomas Fauchez(Universities Space Research Association, GSFC Greenbelt), Anthony B Davis(Jet Propulsion Laboratory), Hironobu Iwabuchi(Graduate School of Science, Tohoku University), Kentaroh Suzuki(Atmosphere and Ocean Research Institute, University of Tokyo), Chairperson:Thomas Fauchez(Universities Space Research Association, GSFC Greenbelt)

12:00 PM - 12:15 PM

[AAS01-10] Radiative Transfer Modeling to Interpret Photopolarimetric Measurements of Brown Dwarf Emissions

★Invited papers

*Suniti Sanghavi1,2 (1.Jet Propulsion Laboratory, 2.California Institute of Technology)

Keywords:Exoplanets, Brown dwarfs, Clouds, Oblateness, Temperature inhomogeneity

We present a novel radiative transfer scheme for computing the disc-resolved and disc-integrated polarized infrared emission of an oblate brown dwarf (BD) or planet. Using this capability, we model oblate cloud-bearing brown dwarfs at different orientations relative to the observer.

The dependence of the photo-polarimetric signal on cloud optical thickness and droplet size, stellar oblateness and inclination are examined qualitatively.

Knowledge of the oblateness and the projected inclination of the stellar axis in the viewing plane together allow the determination of the exact orientation in space of the stellar rotation axis, for both uniform and patchy brown dwarfs. Polarization measurements are most sensitive to the stellar limb, thus providing information complementary to photometric measurements which are susceptible to limb darkening. Information content analysis reveals that polarization can contribute significantly to the quality of the retrieval, especially when measurements can be made with high accuracy.