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arXiv · 1705.07192

Astro-comb calibrator and spectrograph characterization using a turn-key laser frequency comb

Aakash Ravi·David F. Phillips·Matthias Beck·Leopoldo L. Martin·Massimo Cecconi·Adriano Ghedina·Emilio Molinari·Albrecht Bartels·Dimitar Sasselov·Andrew Szentgyorgyi·Ronald L. Walsworth
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Abstract

Using a turn-key Ti:sapphire femtosecond laser frequency comb, an off-the-shelf supercontinuum device, and Fabry-Perot mode filters, we report the generation of a 16 GHz frequency comb spanning a 90 nm band about a center wavelength of 566 nm. The light from this astro-comb is used to calibrate the HARPS-N astrophysical spectrograph for precision radial velocity measurements. The comb-calibrated spectrograph achieves a stability of $\sim$ 1 cm/s within half an hour of averaging time. We also use the astro-comb as a reference for measurements of solar spectra obtained with a compact telescope, and as a tool to study intrapixel sensitivity variations on the CCD of the spectrograph.

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Aakash Ravi, David F. Phillips, Matthias Beck, Leopoldo L. Martin, Massimo Cecconi, Adriano Ghedina, Emilio Molinari, Albrecht Bartels, Dimitar Sasselov, Andrew Szentgyorgyi, Ronald L. Walsworth. 2017-05-19. Astro-comb calibrator and spectrograph characterization using a turn-key laser frequency comb. https://doi.org/10.1117/1.jatis.3.4.045003

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