Activity-Related Radial Velocity Variation in Cool Stars

@article{Saar1997ActivityRelatedRV,
  title={Activity-Related Radial Velocity Variation in Cool Stars},
  author={Steven H. Saar and Robert A. Donahue},
  journal={The Astrophysical Journal},
  year={1997},
  volume={485},
  pages={319-327}
}
Planets have been detected orbiting several solar-type stars with the use of high-precision radial velocity (vr) measurements. While changes in vr can be measured with an accuracy of a few meters per second, there has been relatively little study of how other astrophysical processes, such as magnetic activity, may affect the observed velocities. In this paper, we use published data and simple models to explore the contributions to vr from two activity-related sources, starspots and convective… 
Magnetic Activity-related Radial Velocity Variations in Cool Stars: First Results from the Lick Extrasolar Planet Survey
The discovery of the radial velocity (v -->r) signatures of planets around several solar-like stars highlights the importance of exploring the sources of v -->r variations intrinsic to the stars
Do stellar magnetic cycles influence the measurement of precise radial velocities
The ever increasing level of precision achieved by present and future radial-velocity instruments is opening the way to discovering very low-mass, long-period planets (e.g. solar-system analogs).
Correcting Radial Velocities for Long-Term Magnetic Activity Variations.
  • Saar, Fischer
  • Physics, Geology
    The Astrophysical journal
  • 2000
TLDR
It is argued that the main cause of these effects is modification of the mean line bisector shape brought on by long-term, magnetic activity-induced changes in the surface brightness and convective patterns.
Starspot-Induced Radial Velocity Variability in LkCa 19
We describe a new radial velocity survey of T Tauri stars and present the first results. Our search is motivated by an interest in detecting massive young planets, as well as investigating the origin
Long-term magnetic activity of a sample of M-dwarf stars from the HARPS program I. Comparison of activity indices
Context. The search for extra-solar planets similar to Earth is becoming a reality, but as the level of the measured radial-velocity reaches the sub-ms −1 , stellar intrinsic sources of noise capable
Starspot-Induced Radial Velocity Jitter During a Stellar Cycle
Abstract Late-type stars exhibit cool regions on their surface, the stellar equivalent of sunspots. These dark starspots can also mimic the radial velocity variations caused by orbiting planets,
Disentangling planetary orbits from stellar activity in radial-velocity surveys
Abstract The majority of extra-solar planets have been discovered (or confirmed after follow-up) through radial-velocity (RV) surveys. Using ground-based spectrographs such as High Accuracy Radial
Radial Velocity Variations from Starspots
. In this contribution the radial velocity (RV) variations ex pected for starspots on solar-type stars are examined. The spot-induced RV amplitude is found to vary linearly with spot filling factor
Photospheric activity, rotation, and radial velocity variations of the planet-hosting star CoRoT-7
Context. The CoRoT satellite has recently discovered the transits of an Earth-like planet across the disc of a late-type magnetically active star dubbed CoRoT-7, while a second planet was detected
Separating planetary reflex Doppler shifts from stellar variability in the wavelength domain
Stellar magnetic activity produces time-varying distortions in the photospheric line profiles of solar-type stars. These lead to systematic errors in high-precision radial-velocity measurements,
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