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.

We report on the detections of substellar companions orbiting around seven evolved intermediate-mass stars from precise Doppler measurements at Okayama Astrophysical Observatory. $o$ UMa (G4 II-III) is a giant with a mass of 3.1 $M_{\odot}$ , and hosts a planet with a minimum mass of $m_2$ sin $i$$=$ 4.1 $M_{\rm J}$ in an orbit with a period $P$$=$ 1630 d and an eccentricity $e$$=$ 0.13. This is the first planet candidate ($\lt $ 13 $M_{\rm J}$ ) ever discovered around a star more massive than 3 $M_{\odot}$ . $o$ CrB (K0 III) is a 2.1 $M_{\odot}$ giant, and has a planet of $m_2$ sin $i$$=$ 1.5 $M_{\rm J}$ in a 187.8 d orbit with $e$$=$ 0.19. This is one of the least-massive planets ever discovered around an $\sim$ 2 $M_{\odot}$ star. HD 5608 (K0 IV) is an 1.6 $M_{\odot}$ subgiant hosting a planet of $m_2$ sin $i$$=$ 1.4 $M_{\rm J}$ in a 793 d orbit with $e$$=$ 0.19. The star also exhibits a linear velocity trend, suggesting the existence of an outer, more massive companion. 75 Cet (G3 III:) is a 2.5 $M_{\odot}$ giant hosting a planet of $m_2$ sin $i$$=$ 3.0 $M_{\rm J}$ in a 692 d orbit with $e$$=$ 0.12. The star also shows a possible additional periodicity of about 200 d and 1880 d with a velocity amplitude of $\sim$ 7–10 m s$^{-1}$ , although these are not significant at this stage. $\nu $ Oph (K0 III) is a 3.0 $M_{\odot}$ giant, and has two brown-dwarf companions of $m_2$ sin $i$$=$ 24 $M_{\rm J}$ and 27 $M_{\rm J}$ , in orbits with $P$$=$ 530.3 d and 3190 d, and $e$$=$ 0.126 and 0.17, respectively, which were independently announced by Quirrenbach, Reffert, and Bergmann (2011, AIP Conf. Proc. 1331, 102). The ratio of the periods is close to 1:6, suggesting that the companions are in mean motion resonance. We also independently confirmed planets around $\kappa $ CrB (K0 III-IV) and HD 210702 (K1 IV), which were announced by Johnson et al. (2008, ApJ, 675, 784) and Johnson et al. (2007a, ApJ, 665, 785), respectively. All of the orbital parameters we obtained are consistent with the previous results.

We report the first detection of a hydroxyl radical (OH) emission signature in the planetary atmosphere outside the solar system, in this case, in the dayside of WASP-33b. We analyze high-resolution near-infrared emission spectra of WASP-33b taken using the InfraRed Doppler spectrograph on the 8.2 m Subaru telescope. The telluric and stellar lines are removed using a detrending algorithm, SysRem. The residuals are then cross-correlated with OH and H2O planetary spectrum templates produced using several different line lists. We check and confirm the accuracy of OH line lists by cross-correlating with the spectrum of GJ 436. As a result, we detect the emission signature of OH at K p of km s−1 and v sys of −0.3 km s−1 with a signal-to-noise ratio (S/N) of 5.4 and a significance of 5.5σ. Additionally, we marginally detect H2O emission in the H-band with an S/N of 4.0 and a significance of 5.2σ using the POKAZATEL line list. However, no significant signal is detected using the HITEMP 2010, which might be due to differences in line positions and strengths, as well as the incompleteness of the line lists. Nonetheless, this marginal detection is consistent with the prediction that H2O is mostly thermally dissociated in the upper atmosphere of the ultra-hot Jupiters. Therefore, along with CO, OH is expected to be one of the most abundant O-bearing molecules in the dayside atmosphere of ultra-hot Jupiters and should be considered when studying their atmospheres.

We obtained spectra of the pre-main-sequence star AU Microscopii during a transit of its Neptune-sized planet to investigate its orbit and atmosphere. We used the high-dispersion near-infrared spectrograph InfraRed Doppler (IRD) on the Subaru telescope to detect the Doppler “shadow” from the planet and constrain the projected stellar obliquity. Modeling of the observed planetary Doppler shadow suggests a spin–orbit alignment of the system ( deg), but additional observations are needed to confirm this finding. We use both the IRD data and spectra obtained with NIRSPEC on Keck II to search for absorption in the 1083 nm line of metastable triplet He i by the planet’s atmosphere and place an upper limit for the equivalent width of 3.7 mÅ at 99% confidence. With this limit and a Parker wind model we constrain the escape rate from the atmosphere to M ⊕ Gyr−1, comparable to the rates predicted by an X-ray and ultraviolet energy-limited escape calculation and hydrodynamic models, but refinement of the planet mass is needed for rigorous tests.

In an effort to measure the Rossiter-McLaughlin effect for the TRAPPIST-1 system, we performed high-resolution spectroscopy during transits of planets e, f, and b. The spectra were obtained with the InfraRed Doppler spectrograph on the Subaru 8.2-m telescope, and were supplemented with simultaneous photometry obtained with a 1-m telescope of the Las Cumbres Observatory Global Telescope. By analyzing the anomalous radial velocities, we found the projected stellar obliquity to be λ = 1 ± 28 degrees under the assumption that the three planets have coplanar orbits, although we caution that the radial-velocity data show correlated noise of unknown origin. We also sought evidence for the expected deformations of the stellar absorption lines, and thereby detected the "Doppler shadow" of planet b with a false alarm probability of 1.7 %. The joint analysis of the observed residual cross-correlation map including the three transits gave λ = 19 +13 −15 degrees. These results indicate that the the TRAPPIST-1 star is not strongly misaligned with the common orbital plane of the planets, although further observations are encouraged to verify this conclusion.