About the Research Program
COSMIC: Calibration of spectrographs using microresonator-based frequency combs
The 2019 Nobel Prize in Physics was awarded to Mayor and Queloz for the discovery of the first extrasolar planet around a Sun-like star. They achieved this back in 1995 using precise spectroscopic observations. Since then, several thousand other exoplanets have been found, many of them by stellar spectroscopy. During the orbital motion, an exoplanet imprints a tiny reflex movement its host star, which can be observed as tiny periodic Doppler shift in the stellar spectral lines. Continuous spectrograph recalibration with very high precision is needed to detect this, and for making the method sensitive to Earth-like planets around Sun-like stars, traditional calibration methods are no longer sufficient. In order to break this barrier, many cutting edge astronomical spectrographs have been equipped with frequency comb systems in the past years, which employ complex filtering schemes to make the comb structure resolvable with echelle spectrographs. Our joint collaboration with EPFL (T. Kippenberg) seeks to harness the intrinsically large and easily resolvable mode spacing of a microresonator-based frequency comb, which greatly simplifies the system while at the same time shrinking it down to a chip-type device. The smaller footprint, lower cost and greater ease of operation may promote more widespread adoption of this extremely accurate calibration system perhaps beyond astronomy. Integration of the system into space telescopes may also become an option.
Funding by Eurostars under the program E!113569 is gratefully acknowledged.