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We present evidence for a new two-planet system around the giant star HD202696 (= HIP105056, BD+26 4118). The discovery is based on public HIRES radial velocity measurements taken at Keck Observatory between July 2007 and September 2014. We estimate a stellar mass of 1.91$^{+0.09}_{-0.14}M_odot$ for HD202696, which is located close to the base of the red giant branch. A two-planet self-consistent dynamical modeling MCMC scheme of the radial velocity data followed by a long-term stability test suggests planetary orbital periods of $P_{rm b}$ = 517.8$_{-3.9}^{+8.9}$ days and $P_{rm c}$ = 946.6$_{-20.9}^{+20.7}$ days, eccentricities of $e_{rm b}$ = 0.011$_{-0.011}^{+0.078}$ and $e_{rm c}$ = 0.028$_{-0.012}^{+0.065}$ , and minimum dynamical masses of $m_{rm b}$ = 2.00$_{-0.10}^{+0.22}$,$M_{mathrm{Jup}}$ and $m_{rm c}$ = 1.86$_{-0.23}^{+0.18}$,$M_{mathrm{Jup}}$, respectively. Our stable MCMC samples are consistent with orbital configurations predominantly in a mean period ratio of 11:6 and its close-by high order mean-motion commensurabilities with low eccentricities. For the majority of the stable configurations we find an aligned or anti-aligned apsidal libration (i.e. $Deltaomega$ librating around 0$^circ$ or 180$^circ$), suggesting that the HD202696 system is likely dominated by secular perturbations near the high-order 11:6 mean-motion resonance. The HD202696 system is yet another Jovian mass pair around an intermediate mass star with a period ratio below the 2:1 mean motion resonance. Therefore, the HD202696 system is an important discovery, which may shed light on the primordial disk-planet properties needed for giant planets to break the strong 2:1 mean motion resonance and settle in more compact orbits.
We present results from a radial-velocity survey of 373 giant stars at Lick Observatory, which started in 1999. The previously announced planets iota Dra b and Pollux b are confirmed by continued monitoring. The frequency of detected planetary compan
We report the discovery of planetary companions orbiting four low-luminosity giant stars with M$_star$ between 1.04 and 1.39 M$_odot$. All four host stars have been independently observed by the EXoPlanets aRound Evolved StarS (EXPRESS) program and t
Breakthrough direct detections of planetary companions orbiting A-type stars confirm the existence of massive planets at relatively large separations, but dedicated surveys are required to estimate the frequency of similar planetary systems. To measu
Previous work concerning planet formation around low-mass stars has often been limited to large planets and individual systems. As current surveys routinely detect planets down to terrestrial size in these systems, a more holistic approach that refle
Aims: Our primary goal is to search for planets around intermediate mass stars. We are also interested in studying the nature of radial velocity (RV) variations of K giant stars. Methods: We selected about 55 early K giant (K0 - K4) stars brighter