Bibcode
Gettel, Sara; Adamow, M.; Nowak, G.; Zielinski, P.; Niedzielski, A.; Wolszczan, A.
Bibliographical reference
American Astronomical Society, AAS Meeting #214, #434.11; Bulletin of the American Astronomical Society, Vol. 41, p.706
Advertised on:
5
2009
Citations
0
Refereed citations
0
Description
We describe the status of our long-term radial velocity (RV) survey of a
sample of 1000 GK-giants with the 9.2-m Hobby-Eberly Telescope and its
High Resolution Spectrograph, in search for planetary-mass companions.
The survey uses the I2 cell calibration method to achieve a
4-6 m s-1 precision of RV measurements, which is quite
sufficient, given the observed >20 m s-1 intrinsic RV
variability of these stars. The planets discovered so far include two
published detections of giant planets around HD17092 and HD102272 and a
growing number of plausible candidates currently undergoing the standard
verification process. We present a representative sample of RV curves of
these stars and describe the line bisector and photometry analyses
applied to the data, in order to separate the RV variations generated by
orbiting planets from those resulting from stellar phenomena. We also
discuss the preliminary characteristics of the GK-giant planets
population, which begin to emerge, as its size continues to grow. These
include the previously noted apparent existence of a lower limit to
orbital radii at about 0.6 AU and a possible lack of correlation between
the frequency of occurrence of planets around giants and stellar
metallicity, as well as signatures of the dynamical evolution of planets
discovered by our survey.