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…
323 Citations
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References
SHOWING 1-10 OF 62 REFERENCES
Long, accurate time series measurements of radial velocities of solar-type stars
- Physics, Geology
- 1994
We have been measuring changes in the radial velocities (RV's) of solar-type stars to search for gravitational perturbations by planets. We transmit violet starlight through a Fabry-Perot etalon…
Rotation, convection, and magnetic activity in lower main-sequence stars
- Physics
- 1984
Rotation periods are reported for 14 main-sequence stars, bringing the total number of such stars with well-determined rotation periods to 41. It is found that the mean level of their Ca n H and K…
PROPERTIES OF SUN-LIKE STARS WITH PLANETS: 51 PEGASI,
- Physics, Geology
- 1997
Radial velocity variations have revealed planets orbiting 51 Peg, 47 UMa, and 70 Vir, and a low-mass companion orbiting HD 114762. We analyze parallel records of photometric measurements in Stro…
Rotation, turbulence and evidence for magnetic fields in southern dwarfs
- Physics
- 1997
We model high-resolution spectra using a simple radiative transfer analysis to derive projected rotational velocities (v sin i) and macroturbulent velocity dispersions (vmac) for 49 southern dwarf…
A Search for Jupiter-Mass Companions to Nearby Stars
- Physics, Geology
- 1995
Abstract We have carefully monitored the radial velocities of 21 bright, solar-type stars for 12 years, None has shown any reflex motion due to a substellar companion to an upper limit of between 1…
Properties of Sun-like Stars with Planets: ρ1 Cancri, τ Bootis, and υ Andromedae*
- Physics, Geology
- 1997
Planets have been reported orbiting the Sun-like stars ρ1 Cnc, τ Boo, and υ And based on low-amplitude radial velocity variations. We have derived information on the first two stars from analysis of…
Activity-related characteristics of the convective envelopes in evolving low-mass stars
- Physics
- 1986
Convective envelope structures have been computed for the post-main-sequence evolutionary phases of 0.7-1.6 solar mass model stars having initial mass-fraction abundances of helium and heavier…
A Planet Orbiting 47 Ursae Majoris
- Physics, Geology
- 1996
The G0 V star 47 UMa exhibits very low amplitude radial velocity variations having a period of 2.98 yr, a velocity amplitude of K = 45.5 m s-1, and small eccentricity. The residuals scatter by 11 m…
The Emergence of Magnetic Flux Loops in Sunlike Stars
- Physics
- 1997
We explore the latitude of emergence of flux tubes at the surface of G stars as a function of the rotation rate, magnetic flux, and injection latitude at the bottom of the convective zone. Our…
Line Profile Asymmetries in Chromospherically Active Stars
- Physics
- 1992
A powerful, new probe of chromospheric activity, cross-correlation, has been developed and applied to a variety of stars. In this particular application, an entire CCD spectrum of an active star is…