%0 Journal Article
%A Glenday, Alexander G.
%A Li, Chih-Hao
%A Langellier, Nicholas
%A Chang, Guoqing
%A Chen, Li-Jin
%A Furesz, Gabor
%A Zibrov, Alexander A.
%A Kaertner, Franz
%A Phillips, David F.
%A Sasselov, Dimitar
%A Szentgyorgyi, Andrew
%A Walsworth, Ronald L.
%T Operation of a Broadband Visible-Wavelength Astro-Comb with a High-Resolution Astrophysical Spectrograph
%J Optica
%V 2
%N 3
%@ 2334-2536
%C Washington, DC
%I OSA
%M PUBDB-2015-01536
%P 250 - 254
%D 2015
%X Searches for Earth-like exoplanets using the periodic Doppler shift of stellar absorption lines require 10 cm∕s precision in the measurement of stellar radial velocity (RV) over timescales of years. Current techniques have led to the discovery of short-period exoplanets that induce RV wobbles as small as ≈1 m∕s on their parent stars. It has been suggested that order-of-magnitude improved RV precision may be achievable using an astro-comb, a laser frequency comb optimized for astrophysical spectrograph wavelength calibration. Here we report the development of a broadband visible-wavelength astro-comb and its operation with the HARPS-N spectrograph at the Telescopio Nazionale Galileo in the Canary Islands. This green astrocomb has >7000 narrow (<1 MHz) spectral lines spaced by 16 GHz with relatively uniform line power from 500 to 620 nm. The line frequencies are locked to GPS, enabling us to realize HARPS-N wavelength calibration with RV measurement precision and stability <10 cm∕s.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000354867000010
%R 10.1364/OPTICA.2.000250
%U https://bib-pubdb1.desy.de/record/208059