NOAO >   Observing Info >   Approved Programs >   2009A-0248

# Proposal Information for 2009A-0248

PI: Laird Close, Steward Obs. University of Arizona, lclose@as.arizona.edu
Address: Astronomy Department, 933 N. Cherry Ave., Tucson, AZ 85721, USA

CoI: Daniel Apai, Space Telescope Science Institute
CoI: Ilaria Pascucci, Johns Hopkins University
CoI: Andy Skemer, Steward Obs.

Title: The First Thermal Images of the Planetary Mass Prototype Object 2M1207b: Does it have an Edge-On Disk?

Abstract: Rarely in astronomy is a single object as enigmatic and important as the companion to the young brown dwarf 2M1207A. This companion, which we will call 2M1207b, discovered by Chauvin et al. (2004), is the lowest luminosity "planetary mass" companion known. However, now that we know its distance (58 pc; Biller & Close 2007) it appears that current evolutionary models (like DUSTY) cannot reproduce its high'' 1500 K T_eff and low ~2.2\times10^-5L_\sun luminosity. The proposed edge-on disk model of Mohanty et al. (2007) to explain the apparent low luminosity'' of 2M1207b will be critically tested by our proposed 7 hour (20h with overheads) T-ReCS integration to detect 2M1207b in the sensitive 8.7(mu) m filter in 2009A. Even a gray opacity'' edge-on disk with A_K~3 mag will still be transparent to extinction at 8.7(mu) m, since A_8(mu) m~ 0. Hence the true luminosity of 2M1207b will be revealed at 8.7(mu) m. Our edge-on'' disk models of 2M1207b suggest 8.7(mu) m fluxes of ~0.6 mJy. \bf In 08A this proposal was granted 25h of which only 2h were observed. However, from just 120 min of data we can make a solid and compelling case for an additional 20h to be granted to this important effort in 09A. In 09A we will solve the mystery of 2M1207b and likely have the first thermal image of a planetary mass companion.

National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360

 NOAO >   Observing Info >   Approved Programs >   2009A-0248