Surveying Directly Imaged Planets at High Spectral Resolution with KPIC

The Keck Planet Imager and Characterizer (KPIC) consists of a series of upgrades to the Keck II adaptive optics and instrument suite that can spatially isolate a directly imaged planet and feed its light into the NIRSPEC spectrograph for high resolution (R ~ 35,000) spectroscopy at K and L bands. By studying the shapes of molecular absorption lines in these spectra, we can measure the orbital velocities, spins, and chemical composition of these planets. We demonstrated the capabilities of KPIC by detecting and characterizing the four super-Juptiers orbiting HR 8799. I will discuss this recent result including the tentative trend that planetary spin is correlated with mass, supporting the theory that magnetic breaking at early times is responsible for regulating planetary spins. To confirm this trend as well as look at other population-level trends (e.g., in composition), we are undertaking a survey of all known substellar companions visible from Keck, and I will show early results from this survey in which we have characterized over 20 exoplanet and brown dwarf companions. Additionally, we have measured the sensitivity of this technique and found that KPIC is 10x more sensitive than state-of-the-art high contrast imagers like GPI and SPHERE at close angular separations from the star due to KPIC’s ability to spectrally filter out speckle light. I will discuss the implications of this and new hardware improvements to KPIC that we are currently commissioning that will further improve its sensitivity.