Doppler measurements from Subaru and Keck have revealed radial velocity variations in the V ¼ 8:15, G0 IV star HD 149026 consistent with a Saturn-mass planet in a 2.8766 day orbit. Photometric observations at Fairborn Observatory have detected three complete transit events with depths of 0.003 mag at the predicted times of conjunction. HD 149026 is now the second-brightest star with a transiting extrasolar planet. The mass of the star, based on interpolation of stellar evolutionary models, is 1:3 AE 0:1 M ; together with the Doppler amplitude K 1 ¼ 43:3 m s À1 , we derive a planet mass M sin i ¼ 0:36M J and orbital radius 0.042 AU. HD 149026 is chromospherically inactive and metal-rich with spectroscopically derived ½ Fe/ H ¼ þ0:36, T eA ¼ 6147 K, log g ¼ 4:26, and v sin i ¼ 6:0 km s À1 . Based on T eff and the stellar luminosity of 2.72 L , we derive a stellar radius of 1.45 R . Modeling of the three photometric transits provides an orbital inclination of 85N3 AE 1N0 and (including the uncertainty in the stellar radius) a planet radius of (0:725 AE 0:05) R J . Models for this planet mass and radius suggest the presence of a $67 M È core composed of elements heavier than hydrogen and helium. This substantial planet core would be difficult to construct by gravitational instability.

We report the detection of five Jovian mass planets orbiting high metallicity stars. Four of these stars were first observed as part of the N2K program and exhibited low RMS velocity scatter after three consecutive observations. However, follow-up observations over the last three years now reveal the presence of -2longer period planets with orbital periods ranging from 21 days to a few years. HD 11506 is a G0V star with a planet of M sin i = 4.74 M JUP in a 3.85 year orbit. HD 17156 is a G0V star with a 3.12 M JUP planet in a 21.2 day orbit. The eccentricity of this orbit is 0.67, one of the highest known for a planet with a relatively short period. The orbital period for this planet places it in a region of parameter space where relatively few planets have been detected. HD 125612 is a G3V star with a planet of M sin i = 3.5 M JUP in a 1.4 year orbit. HD 170469 is a G5IV star with a planet of M sin i = 0.67 M JUP in a 3.13 year orbit. HD 231701 is an F8V star with planet of 1.08 M JUP in a 142 day orbit. All of these stars have supersolar metallicity. Three of the five stars were observed photometrically but showed no evidence of brightness variability. A transit search conducted for HD 17156 was negative but covered only 25% of the search space and so is not conclusive.

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We report the detection of a substellar companion orbiting the intermediatemass giant star 11 Com (G8 III). Precise Doppler measurements of the star from Xinglong station and Okayama Astrophysical Observatory (OAO) revealed Keplerian velocity variations with an orbital period of 326.03±0.32 days, a semiamplitude of 302.8±2.6 m s −1 , and an eccentricity of 0.231±0.005. Adopting a stellar mass of 2.7±0.3 M ⊙ , the minimum mass of the companion is 19.4±1.5 M J , well above the deuterium burning limit, and the semimajor axis is 1.29±0.05 AU. This

We report on the detection of 3 new extrasolar planets from a precise Doppler survey of G and K giants at Okayama Astrophysical Observatory. The host stars, 18 Del (G6 III), Aql (K0 III) and HD 81688 (K0 III-IV), are located in the clump region on the HR diagram with estimated masses of 2.1-2.3M ˇ. 18 Del b has a minimum mass of 10:3M J and resides in a nearly circular orbit with period of 993 d, which is the longest one around evolved stars.Aql b and HD 81688 b have minimum masses of 2.8 and 2.7M J , and reside in nearly circular orbits with periods of 137 and 184 d, respectively, which are the shortest ones around evolved stars. All of the substellar companions ever discovered around intermediate-mass (1.7-3.9M ˇ) clump giants have semimajor axes larger than 0.68 AU, suggesting a lack of short-period planets. Our numerical calculations suggest that Jupiter-mass planets within about 0.5 AU (even up to 1 AU, depending on the metallicity and adopted models) around 2-3M ˇstars could be engulfed by the central stars at the tip of RGB due to tidal torque from the central stars. Assuming that most of the clump giants are post-RGB stars, we can not distinguish whether the lack of short-period planets is primordial, or due to engulfment by central stars.