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Catalog of Nearby Exoplanets
We present a catalog of nearby exoplanets. It contains the 172 knownlow-mass companions with orbits established through radial velocity andtransit measurements around stars within 200 pc. We include fivepreviously unpublished exoplanets orbiting the stars HD 11964, HD 66428,HD 99109, HD 107148, and HD 164922. We update orbits for 83 additionalexoplanets, including many whose orbits have not been revised sincetheir announcement, and include radial velocity time series from theLick, Keck, and Anglo-Australian Observatory planet searches. Both thesenew and previously published velocities are more precise here due toimprovements in our data reduction pipeline, which we applied toarchival spectra. We present a brief summary of the global properties ofthe known exoplanets, including their distributions of orbital semimajoraxis, minimum mass, and orbital eccentricity.Based on observations obtained at the W. M. Keck Observatory, which isoperated jointly by the University of California and the CaliforniaInstitute of Technology. The Keck Observatory was made possible by thegenerous financial support of the W. M. Keck Foundation.
| The N2K Consortium. III. Short-Period Planets Orbiting HD 149143 and HD 109749
We report the detection of two short-period planets discovered at KeckObservatory. HD 149143 is a metal-rich G0 IV star with a planet ofMsini=1.33MJ and an orbital radius of 0.053 AU. The best-fitKeplerian model has an orbital period, P=4.072 days, semivelocityamplitude, K=149.6 m s-1, and eccentricity, e=0.016+/-0.01.The host star is chromospherically inactive and metal-rich, with[Fe/H]=0.26. Based on the Teff and stellar luminosity, wederive a stellar radius of 1.49 Rsolar. Photometricobservations of HD 149143 were carried out using the automatedphotometric telescopes at Fairborn Observatory. HD 149143 isphotometrically constant over the radial velocity period to0.0003+/-0.0002 mag, supporting the existence of the planetarycompanion. No transits were detected down to a photometric limit ofapproximately 0.02%, eliminating transiting planets with a variety ofcompositions and constraining the orbital inclination to less than83°. A short-period planet was also detected around HD 109749, a G3IV star. HD 109749 is chromospherically inactive, with [Fe/H]=0.25 and astellar radius of 1.24. The radial velocities for HD 109749 are modeledby a Keplerian with P=5.24 days and K=28.7 m s-1. Theinferred planet mass is Msini=0.28MJ and the semimajor axisof this orbit is 0.0635 AU. Photometry of HD 109749 was obtained withthe SMARTS consortium telescope, the PROMPT telescope, and bytransitsearch.org observers in Adelaide and Pretoria. These observationsdid not detect a decrement in the brightness of the host star at thepredicted ephemeris time, and they constrain the orbital inclination toless than 85° for gas giant planets with radii down to0.7RJ.Based on observations obtained at the W. M. Keck Observatory, which isoperated as a scientific partnership among the California Institute ofTechnology, the University of California, and the National Aeronauticsand Space Administration (NASA). The Observatory was made possible bythe generous financial support of the W. M. Keck Foundation. The authorswish to recognize and acknowledge the very significant cultural role andreverence that the summit of Mauna Kea has always had within theindigenous Hawaiian community. We are most fortunate to have theopportunity to conduct observations from this mountain. Keck time hasbeen granted by the National Optical Astronomy Observatory (NOAO) andNASA.
| Elodie metallicity-biased search for transiting Hot Jupiters. I. Two Hot Jupiters orbiting the slightly evolved stars HD 118203 and HD 149143
We report the discovery of a new planet candidate orbiting the subgiantstar HD 118203 with a period of P = 6.1335 days. Thebest Keplerian solution yields an eccentricity e = 0.31 and a minimummass m_2 sin{i} = 2.1 M_Jup for the planet. This star has been observedwith the ELODIE fiber-fed spectrograph as one of the targets in ourplanet-search programme biased toward high-metallicity stars, on-goingsince March 2004 at the Haute-Provence Observatory. An analysis of thespectroscopic line profiles using line bisectors revealed no correlationbetween the radial velocities and the line-bisector orientations,indicating that the periodic radial-velocity signal is best explained bythe presence of a planet-mass companion. A linear trend is observed inthe residuals around the orbital solution that could be explained by thepresence of a second companion in a longer-period orbit. We also presenthere our orbital solution for another slightly evolved star in ourmetal-rich sample, HD 149143, recently proposed tohost a 4-d period Hot Jupiter by the N2K consortium. Our solution yieldsa period P = 4.09 days, a marginally significant eccentricity e = 0.08and a planetary minimum mass of 1.36 M_Jup. We checked that the shape ofthe spectral lines does not vary for this star as well.
| The N2K Consortium. II. A Transiting Hot Saturn around HD 149026 with a Large Dense Core
Doppler measurements from Subaru and Keck have revealed radial velocityvariations in the V=8.15, G0 IV star HD 149026 consistent with aSaturn-mass planet in a 2.8766 day orbit. Photometric observations atFairborn Observatory have detected three complete transit events withdepths of 0.003 mag at the predicted times of conjunction. HD 149026 isnow the second-brightest star with a transiting extrasolar planet. Themass of the star, based on interpolation of stellar evolutionary models,is 1.3+/-0.1 Msolar together with the Doppler amplitudeK1=43.3 m s-1, we derive a planet massMsini=0.36MJ and orbital radius 0.042 AU. HD 149026 ischromospherically inactive and metal-rich with spectroscopically derived[Fe/H]=+0.36, Teff=6147 K, logg=4.26, and vsini=6.0 kms-1. Based on Teff and the stellar luminosity of2.72 Lsolar, we derive a stellar radius of 1.45Rsolar. Modeling of the three photometric transits providesan orbital inclination of 85.3d+/-1.0d and (including the uncertainty inthe stellar radius) a planet radius of (0.725+/-0.05)RJ.Models for this planet mass and radius suggest the presence of a ~67M⊕ core composed of elements heavier than hydrogen andhelium. This substantial planet core would be difficult to construct bygravitational instability.Based on data collected at the Subaru Telescope, which is operated bythe National Astronomical Observatory of Japan.Based on observations obtained at the W. M. Keck Observatory, which isoperated by the University of California and the California Institute ofTechnology. Keck time has been granted by NOAO and NASA.
| ELODIE metallicity-biased search for transiting Hot Jupiters. II. A very hot Jupiter transiting the bright K star HD 189733
Context: .Among the 160 known exoplanets, mainly detected in largeradial-velocity surveys, only 8 have a characterization of their actualmass and radius thanks to the two complementary methods of detection:radial velocities and photometric transit. Aims: .We started inMarch 2004 an exoplanet-search programme biased toward high-metallicitystars which are more frequently host extra-solar planets. This surveyaims to detect close-in giant planets, which are most likely to transittheir host star. Methods: .For this programme, high-precisionradial velocities are measured with the ELODIE fiber-fed spectrograph onthe 1.93-m telescope, and high-precision photometry is obtained with theCCD Camera on the 1.20-m telescope, both at the Haute-ProvenceObservatory. Results: .We report here the discovery of a newtransiting hot Jupiter orbiting the star HD 189733. The planetary natureof this object is confirmed by the observation of both the spectroscopicand photometric transits. The exoplanet HD 189733 b, with an orbitalperiod of 2.219 days, has one of the shortest orbital periods detectedby radial velocities, and presents the largest photometric depth in thelight curve (3%) observed to date. We estimate for the planet amass of 1.15±0.04 MJ and a radius of 1.26±0.03RJ. Considering that HD 189733 has the same visual magnitudeas the well known exoplanet host star HD 209458, further ground-basedand space-based follow-up observations are very promising and willpermit a characterization of the atmosphere and exosphere of this giantexoplanet.
| Stroemgren photometry of F- and G-type stars brighter than V = 9.6. I. UVBY photometry
Within the framework of a large photometric observing program, designedto investigate the Galaxy's structure and evolution, Hβ photometryis being made for about 9000 stars. As a by-product, supplementary uvbyphotometry has been made. The results are presented in a cataloguecontaining 6924 uvby observations of 6190 stars, all south ofδ=+38deg. The overall internal rms errors of one observation(transformed to the standard system) of a program star in the interval6.5
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| Сазвежђа: | Змијоносац |
| Ректацензија: | 16h32m51.05s |
| Deклинација: | +02°05'05.4" |
| Apparent магнитуда: | 7.902 |
| Даљина: | 63.492 parsecs |
| Proper motion RA: | -9.9 |
| Proper motion Dec: | -85 |
| B-T magnitude: | 8.711 |
| V-T magnitude: | 7.969 |
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