This work will perform a near-infrared precision radial velocity survey of 100 late M-dwarf stars and brown dwarfs in order to search for new Saturn- or Jupiter-mass exoplanets. The PI and his team plan to use an ammonia gas cell with the IRCS spectrograph on the 8-m Subaru Telescope in order to obtain moderate-resolution spectra of exoplanets. They will then use these measurements to constrain models of planet formation. The team plans to make the cell available to US investigators, which will greatly aid in follow-up radial velocity studies for confirmation of exoplanet discoveries. Undergraduate students in be supervised and mentored in research, including observational and data reduction techniques.