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arXiv · 1510.05602

Attaining Doppler Precision of 10 cm/s with a Lock-In Amplified Spectrometer

Rebecca Jensen-Clem·Philip S. Muirhead·Michael Bottom·J. Kent Wallace·Gautam Vasisht·John Asher Johnson
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Abstract

We explore the radial velocity performance benefits of coupling starlight to a fast-scanning interferometer and a fast-readout spectrometer with zero readout noise. By rapidly scanning an interferometer we can decouple wavelength calibration errors from precise radial velocity measurements, exploiting the advantages of lock-in amplification. In a Bayesian framework, we investigate the correlation between wavelength calibration errors and resulting radial velocity errors. We construct an end-to-end simulation of this approach to address the feasibility of achieving 10 cm/s radial velocity precision on a typical Sun-like star using existing, 5-meter-class telescopes. We find that such a precision can be reached in a single night, opening up possibilities for ground-based detections of Earth-Sun analog systems.

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Rebecca Jensen-Clem, Philip S. Muirhead, Michael Bottom, J. Kent Wallace, Gautam Vasisht, John Asher Johnson. 2015-10-19. Attaining Doppler Precision of 10 cm/s with a Lock-In Amplified Spectrometer. https://doi.org/10.1086/683796

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