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arXiv · 1410.7379

Towards Understanding Stellar Radial Velocity Jitter as a Function of Wavelength: The Sun as a Proxy

Robert C. Marchwinski·Suvrath Mahadevan·Paul Robertson·Lawrence Ramsey·Jerald Harder
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Abstract

Using solar spectral irradiance measurements from the SORCE spacecraft and the F/F' technique, we have estimated the radial velocity (RV) scatter induced on the Sun by stellar activity as a function of wavelength. Our goal was to evaluate the potential advantages of using new near-infrared (NIR) spectrographs to search for low-mass planets around bright F, G, and K stars by beating down activity effects. Unlike M dwarfs, which have higher fluxes and therefore greater RV information content in the NIR, solar-type stars are brightest at visible wavelengths, and, based solely on information content, are better suited to traditional optical RV surveys. However, we find that the F/F' estimated RV noise induced by stellar activity is diminished by up to a factor of 4 in the NIR versus the visible. Observations with the upcoming future generation of NIR instruments can be a valuable addition to the search for low-mass planets around bright FGK stars in reducing the amount of stellar noise affecting RV measurements.

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Robert C. Marchwinski, Suvrath Mahadevan, Paul Robertson, Lawrence Ramsey, Jerald Harder. 2014-10-27. Towards Understanding Stellar Radial Velocity Jitter as a Function of Wavelength: The Sun as a Proxy. https://doi.org/10.1088/0004-637x%2F798%2F1%2F63

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