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تسجيل مستخدم جديدA compact green Ti:Sapphire astro-comb with 43-GHz repetition frequency
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A compact green astro-comb with 43-GHz repetition rate is developed based on a Ti:Sapphire optical frequency comb (OFC) and a mode-selecting cavity. The OFCs large repetition rate of 1.6 GHz eases the requirements for the mode-selecting cavity. Unnecessary frequency-modes of the OFC are suppressed down to $5 times 10^{-4}$ at 535 nm - 550 nm using a single mode-selecting cavity with 70-MHz linewidth. The radial velocity precision $sigma sim 1.4$ m/s is achieved at the High Dispersion Echelle Spectrosraph for the Okayama 188-cm telescope of the National Astronomical Observatory of Japan using our astro-comb. With further improvements of the mode-selecting cavity and removal of fiber modal noises, our system will provide a simple, compact, and precise astro-comb setup in visible wavelength region.
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