Equipment: MRI: Track 2 - Development of an ultra-high precision wavelength-calibration system for the Large Binocular Telescope

Scientists detect exoplanets by using spectrographs that measure tiny changes in the color of starlight caused by stars wobbling back and forth as planets orbit around them. In 1995 this method was used to detect the first exoplanet in orbit around a star like the Sun, a breakthrough recognized with the Nobel Prize in Physics in 2019. Finding even smaller exoplanets in the future, including those like Earth, requires careful calibration of the spectrographs that make these measurements. With funds from NSF’s Major Research Instrumentation program, this team will procure, install, and optimize a new “laser frequency comb” calibration source for two spectrographs at the 8.4-meter Large Binocular Telescope in Arizona. In addition, this project will contribute to training the next generation of scientists and engineers, and graduate students will lead key program elements while being mentored by senior members of the team in training and career development. High resolution spectroscopic measurements will play an essential role in exoplanet science. In addition to supporting transit surveys, the radial velocity (RV) method will also play a critical role in the characterization of planets discovered by future direct imaging missions. To accomplish these goals it is crtical that we continue to advance the sensitivity, resolution, and precision of extreme precision radial velocity (EPRV) spectrographs. This project will deliver a state-of-the-art Laser Frequency Comb (LFC) to the Large Binocular Telescope (LBT) and complete its optimized integration, enabling critical multi-year spectroscopic studies with the Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) and iLocater spectrograph. With their precision high-resolution (R>190,000) capabilities spanning visible (PEPSI: 383-912nm) and near-infrared (iLocater: 970-1310nm) wavelengths on a dual 8.4m telescope, these instruments are optimized for EPRV studies of exoplanets and stellar astrophysics. Augmenting them with a dedicated LFC with its absolute wavelength calibration capabilities enables robust intercalibration between LBT instruments and expands short-term instrument performance to multi-year baselines. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.