Radial velocity planet detection biases at the stellar rotational period

July 2016 • 2016MNRAS.459.3565V

Authors • Vanderburg, Andrew • Plavchan, Peter • Johnson, John Asher • Ciardi, David R. • Swift, Jonathan • Kane, Stephen R.

Abstract • Future generations of precise radial velocity (RV) surveys aim to achieve sensitivity sufficient to detect Earth mass planets orbiting in their stars' habitable zones. A major obstacle to this goal is astrophysical RV noise caused by active areas moving across the stellar limb as a star rotates. In this paper, we quantify how stellar activity impacts exoplanet detection with radial velocities as a function of orbital and stellar rotational periods. We perform data-driven simulations of how stellar rotation affects planet detectability and compile and present relations for the typical time-scale and amplitude of stellar RV noise as a function of stellar mass. We show that the characteristic time-scales of quasi-periodic RV jitter from stellar rotational modulations coincides with the orbital period of habitable-zone exoplanets around early M-dwarfs. These coincident periods underscore the importance of monitoring the targets of RV habitable-zone planet surveys through simultaneous photometric measurements for determining rotation periods and activity signals, and mitigating activity signals using spectroscopic indicators and/or RV measurements at different wavelengths.

Links

• SIMBAD http://simbad.u-strasbg.fr/simbo.pl?bibcode=2016MNRAS.459.3565V
• PDF https://academic.oup.com/mnras/pdf-lookup/doi/10.1093/mnras/stw863
• PREPRINT http://arxiv.org/abs/1604.03143
• ELECTR https://doi.org/10.1093%2Fmnras%2Fstw863