PI: Robert T Zellem, U. of Arizona, T.Zellem@jpl.nasa.gov
Address: Lunar and Planetary Laboratory, 1629 E University Blvd, Tucson, Arizona 85721 United States
CoI: Caitlin Griffith, U. of Arizona
CoI: Kyle A Pearson, Northern Arizona U.
CoI: Ingo P Waldmann, University College London
Title: High Precision Measurements of an Exoplanet's Radius
Abstract: We propose to use Mayall/KOSMOS to accurately measure the radius of the exoplanet XO-2b in support of scheduled HST/WFC3 observations. Transiting exoplanet data are complicated by model degeneracies between the atmospheric pressure level and atmospheric composition: a transit signal can be explained by a thick atmosphere and small radius or vice versa. Thus, previous studies can constrain molecular abundances to only $\sim$3--5 orders of magnitude. In addition, ground-based observations are fraught with systematic errors that arise from the instrument and local atmospheric effects, which pollute the exoplanet's signal. However, simultaneous observations from multiple platforms can be used to extract the planetary signal with high precision because it is common among the platforms. Mayall/KOSMOS observations, coupled with the Discovery Channel Telescope and undersubscribed Kuiper 61'' Telescope, will measure XO-2b's Rayleigh scattering and determine an upper limit of its radius at a specified pressure level. These data will crucially support our awarded, upcoming Hubble/WFC3 observations by greatly limiting the degeneracy of the retrieved abundances and thermal profile to a factor of 3.
Program Type: Standard/Solar System
Run 1 (2015A): KP-4m/KOSMOS -- 3n on Feb 06 - Feb 07 2015, Feb 28 2015
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360