Properties of F Stars with Stable Radial Velocity Timeseries: A Useful Metric for Selecting Low-jitter F Stars

Abstract

In a companion paper, we have conducted an in-depth analysis of radial velocity jitter of over 600 stars, examining the astrophysical origins including stellar granulation, oscillation, and magnetic activity. In this paper, we highlight a subsample of those stars, specifically the main sequence and "retired" F stars -- which we refer to as "MSRF" stars -- that show low levels of RV jitter ($<10$ m/s). We describe the observational signatures of these stars that allow them to be identified in radial velocity planet programs, for instance those performing follow-up of transiting planets discovered by TESS. We introduce a "jitter metric" that combines the two competing effects of RV jitter with age: activity and convection. Using thresholds in the jitter metric, we can select both "complete" and "pure" samples of low jitter F stars. We also provide recipes for identifying these stars using only Gaia colors and magnitudes. Finally, we describe a region in the Gaia color-magnitude diagram where low jitter F stars are most highly concentrated. By fitting a 9th order polynomial to the Gaia main sequence, we use the height above the main sequence as a proxy for evolution, allowing for a crude selection of low jitter MSRF stars when activity measurements are otherwise unavailable.

arXiv comment10 pages, 8 figures, published in The Astronomical Journal

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Cited by in corpus (6)

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• Towards a direct measure of the Galactic acceleration
• Spatially resolved spectroscopy across stellar surfaces. V. Observational prospects: Toward Earth-like exoplanet detection
• The CARMENES search for exoplanets around M dwarfs. The impact of rotation and magnetic fields on the radial velocity jitter in cool stars
• Exploring the robustness of Keplerian signals to the removal of active and telluric features