Program: GN-2016A-Q-37

We propose to obtain the first near-infrared spectra of the young (~7 Myr) 12-20 Mjup planetary-mass companion ROXs 12 b with Gemini/NIFS. Spectroscopy will enable us to confirm its low temperature and low mass, which is especially important at young ages when an edge-on disk around a brown dwarf can mimic the expected photospheric properties of a planet. In addition, moderate-resolution spectroscopy opens the possibility of identifying emission lines associated with accretion from a circum-planetary disk, which is suggested by excess infrared emission. If confirmed, a circum-planetary disk around ROXs 12 b will provide important clues about its formation, suggesting an in situ mechanism (disk instability or cloud fragmentation) as opposted to planet-planet scattering, which may be destructive to circum-planetary disks.