Stellar spectroscopy in the near-infrared with a laser frequency comb

• DOI: 10.1364/optica.6.000233
• Publication Date: 2019-02-19T15:54:36Z
• Authors: Andrew J. Metcalf; Tyler Anderson; Chad F. Bender; Scott Blakeslee; Wesley Brand; David R. Carlson; William D. Cochran; Scott A. Diddams; Michael Endl; Connor Fredrick; Sam Halverson; Daniel D. Hickstein; Fred Hearty; Jeff Jennings; Shubham Kanodia; Kyle F. Kaplan; Eric Levi; Emily Lubar; Suvrath Mahadevan; Andrew Monson; Joe P. Ninan; Colin Nitroy; Steve Osterman; Scott B. Papp; Franklyn Quinlan; Larry Ramsey; Paul Robertson; Arpita Roy; Christian Schwab; Steinn Sigurdsson; Kartik Srinivasan; Gudmundur Stefansson; David A. Sterner; Ryan Terrien; Alex Wolszczan; Jason T. Wright; Gabriel Ycas
• Keywords: Earth and Planetary Astrophysics (astro-ph.EP); 0103 physical sciences; FOS: Physical sciences; Astrophysics - Instrumentation and Methods for Astrophysics; 530; Instrumentation and Methods for Astrophysics (astro-ph.IM); 01 natural sciences; 520; Astrophysics - Earth and Planetary Astrophysics; Physics - Optics; Optics (physics.optics)

The discovery and characterization of exoplanets around nearby stars is driven by profound scientific questions about the uniqueness of Earth and our Solar System, and the conditions under which life could exist elsewhere in our Galaxy. Doppler spectroscopy, or the radial velocity (RV) technique, has been used extensively to identify hundreds of exoplanets, but with notable challenges in detecting terrestrial mass planets orbiting within habitable zones. We describe infrared RV spectroscopy at the 10 m Hobby-Eberly telescope that leverages a 30 GHz electro-optic laser frequency comb with nanophotonic supercontinuum to calibrate the Habitable Zone Planet Finder spectrograph. Demonstrated instrument precision <10 cm/s and stellar RVs approaching 1 m/s open the path to discovery and confirmation of habitable zone planets around M-dwarfs, the most ubiquitous type of stars in our Galaxy.