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arXiv · 0911.2008

Starspot Jitter in Photometry, Astrometry and Radial Velocity Measurements

V. V. Makarov·C. A. Beichman·J. H. Catanzarite·D. A. Fischer·J. Lebreton·F. Malbet·M. Shao
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Abstract

Analytical relations are derived for the amplitude of astrometric, photometric and radial velocity perturbations caused by a single rotating spot. The relative power of the star spot jitter is estimated and compared with the available data for $\kappa^1$ Ceti and HD 166435, as well as with numerical simulations for $\kappa^1$ Ceti and the Sun. A Sun-like star inclined at $i=90\degr$ at 10 pc is predicted to have a RMS jitter of 0.087 \uas in its astrometric position along the equator, and 0.38 m s$^{-1}$ in radial velocities. If the presence of spots due to stellar activity is the ultimate limiting factor for planet detection, the sensitivity of SIM Lite to Earth-like planets in habitable zones is about an order of magnitude higher that the sensitivity of prospective ultra-precise radial velocity observations of nearby stars.

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V. V. Makarov, C. A. Beichman, J. H. Catanzarite, D. A. Fischer, J. Lebreton, F. Malbet, M. Shao. 2009-11-10. Starspot Jitter in Photometry, Astrometry and Radial Velocity Measurements. https://doi.org/10.1088/0004-637x/707/1/l73

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