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

TL;DR

This paper demonstrates that coupling a fast-scanning interferometer with a zero-readout-noise spectrometer can achieve 10 cm/s radial velocity precision, enabling ground-based detection of Earth-like exoplanets within a single night.

Contribution

It introduces a novel spectrometer setup with lock-in amplification and Bayesian analysis to decouple calibration errors from radial velocity measurements.

Findings

Achieves 10 cm/s radial velocity precision in simulations

Can detect Earth-like planets with existing telescopes in one night

Decouples calibration errors from velocity measurements

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.