Speaker
Description
The upcoming Extremely Large Telescopes (ELTs) will have the collecting area required to detect potential biosignature gases such as molecular oxygen, O2, in the atmosphere of terrestrial planets around nearby stars. To maximize our capability to detect O2 using this method, extreme high spectral resolution R=300,000-500,000 is required to fully resolve the absorption lines in an exoplanet atmosphere and disentangle telluric lines from our own atmosphere. Current high-resolution spectrographs typically achieve spectral resolution of R=100,000. We demonstrate a new approach with an ultra-high spectral resolution booster to be coupled in front of a high-resolution spectrograph. The booster is a chained Fabry Perot array which imposes a hyperfine chained spectral profile. With a prototype we developed, our on-sky observations of the solar spectrum around the O2 A-band demonstrate a resolving power of R=450,000. The capabilities of this instrument for exoplanet characterization are substantiated by detection of multiple atomic species, Ni I, Fe I, Mg I, K, and Si, hidden among the molecular oxygen feature.