Stellar Companions to Stars with Planets
A combination of high-resolution and wide-field imaging reveals twobinary stars and one triple star system among the sample of the first 11stars with planets detected by radial velocity variations.High-resolution speckle or adaptive optics (AO) data probe subarcsecondscales down to the diffraction limit of the Keck 10 m or the Lick 3 m,and direct images or AO images are sensitive to a wider field, extendingto 10" or 38", depending on the camera. One of the binary system-HD114762-was not previously known to be a spatially resolved multiplesystem; additional data taken with the combination of Keck adaptiveoptics and NIRSPEC are used to characterize the new companion. Thesecond binary system-τ Boo-was a known multiple with two conflictingorbital solutions; the current data will help constrain the discrepantestimates of periastron time and separation. Another target-16 Cyg B-wasa known common proper motion binary, but the current data resolve a newthird component, close to the wide companion 16 Cyg A. Both the HD114762 and 16 Cyg B systems harbor planets in eccentric orbits, whilethe τ Boo binary contains an extremely close planet in a tidallycircularized orbit. Although the sample is currently small, theproportion of binary systems is comparable to that measured in the fieldover a similar separation range. Incorporating the null result fromanother companion search project lowers the overall fraction of planetsin binary systems, but the detections in our survey reveal that planetscan form in binaries separated by less than 50 AU.
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Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i
This work is the second part of the set of measurements of v sin i forA-type stars, begun by Royer et al. (\cite{Ror_02a}). Spectra of 249 B8to F2-type stars brighter than V=7 have been collected at Observatoirede Haute-Provence (OHP). Fourier transforms of several line profiles inthe range 4200-4600 Å are used to derive v sin i from thefrequency of the first zero. Statistical analysis of the sampleindicates that measurement error mainly depends on v sin i and thisrelative error of the rotational velocity is found to be about 5% onaverage. The systematic shift with respect to standard values fromSlettebak et al. (\cite{Slk_75}), previously found in the first paper,is here confirmed. Comparisons with data from the literature agree withour findings: v sin i values from Slettebak et al. are underestimatedand the relation between both scales follows a linear law ensuremath vsin inew = 1.03 v sin iold+7.7. Finally, thesedata are combined with those from the previous paper (Royer et al.\cite{Ror_02a}), together with the catalogue of Abt & Morrell(\cite{AbtMol95}). The resulting sample includes some 2150 stars withhomogenized rotational velocities. Based on observations made atObservatoire de Haute Provence (CNRS), France. Tables \ref{results} and\ref{merging} are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.125.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/393/897
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Search for low-mass PMS companions around X-ray selected late B stars
We have observed 49 X-ray-detected bright late B-type dwarfs to searchfor close low-mass pre-main sequence (PMS) companions using the EuropeanSouthern Observatory's ADONIS (Adaptive Optics Near Infrared System)instrument. We announce the discovery of 21 new companions in 9binaries, 5 triple, 4 quadruple system and 1 system consisting of fivestars. The detected new companions have K magnitudes between 6.5m and17.3m and angular separations ranging from 0.12 arcsec to 14.1 arcsec(18-2358 AU). Based on observations obtained at the European SouthernObservatory, La Silla, Chile (ESO programme No.~62.I-0477, and Swiss70~cm photometric telescope).
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CCD measurements of visual double stars made with the 50 CM refractor of the Nice Observatory
We present the measurements of 49 visual double stars made in 1997 withthe 50 cm refractor of the Nice Observatory (Table 1). A CCD camera wasattached to this refractor. Some new binaries discovered by Hipparcoshave been measured. The algorithm used for these measurements is basedon the adjustment of a tridimensional mathematical surface. Table 1 isalso available in electronic form at CDS viahttp://cdsweb.u-strasbg.fr/Abstract.html }
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The ROSAT all-sky survey catalogue of optically bright main-sequence stars and subgiant stars
We present X-ray data for all main-sequence and subgiant stars ofspectral types A, F, G, and K and luminosity classes IV and V listed inthe Bright Star Catalogue that have been detected as X-ray sources inthe ROSAT all-sky survey; several stars without luminosity class arealso included. The catalogue contains 980 entries yielding an averagedetection rate of 32 percent. In addition to count rates, sourcedetection parameters, hardness ratios, and X-ray fluxes we also listX-ray luminosities derived from Hipparcos parallaxes. The catalogue isalso available in electronic form via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJS...99..135A&db_key=AST
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Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
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Search for systematic effects in photographic measurements of visual binaries
Photographic plates (265) of selected visual double stars obtained bymeans of the 105 cm astrometric reflector of the AstronomicalObservatory of Torino have been taken during 1984. 118 visual doublestars of this series of observations (the 7th) have been measured twiceby two persons using two different measuring machines. In this paper thesingle measures of the polar coordinates for each person and the averagevalues obtained combining the two types of measures are reported. Ananalysis of the systematic errors due to the two systems of measurementand considerations about the type of motion of each binary are given.
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Photographic measures of visual binaries
A fourth series of photographic measures of selected visual binaries hasbeen obtained with the astrometric reflector of the AstronomicalObservatory of Torino. This series contains 143 accurate measures of theastrometric parameters rho and theta which are the result of a criticalselection among the observations. Those having deviations from the meanrho larger than 3 sigma = 0.08 arcsec were rejected. The date ofobservation, angular separation, position angle, and number of exposuresper plate are given.
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Further Studies of A-Stars and F-Stars in the Region of the North Galactic Pole - Part Four - a Catalogue of Uvbyr Photometry and Derived Quantities
Not Available
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Further Studies of A-Stars and F-Stars in the Region of the North Galactic Pole - Part Three - a Catalogue of Star Names and Positions
Not Available
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Photographic measures of double stars. II
Measures are presented for 302 double stars photographed on 657 plateswith the 36-in. Lick refractor in the period between 1945 and 1962. Thedata provided include the observing epochs, the rectangular coordinatesof the secondary components with reference to the respective primaries,the mean errors of a single measurement, the computed mean errors, thedouble-star separations, and the position angles both for the observingepoch and reduced to the equator of 2000. An additional 561 unmeasuredplates of acceptable quality obtained between 1948 and 1960 are listed.
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Spectral classification and UBV photometry of bright visual double stars
Spectral types, luminosity classes, and photoelectric UBV magnitudes arepresented for the components of 91 visual double-star systems. Thespectrograms used for classification were obtained with a reciprocaldispersion of 128 A/mm, and the UBV observations were made at projecteddiaphragm sizes of 15, 20, and 33 arcsec. The problem of scattered lightarising during photoelectric observations of visual binaries isdiscussed.
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Rotational Velocities of a0 Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974ApJS...28..101D&db_key=AST
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The Motions of the A Stars at the North Galactic Pole
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969PASP...81..741E&db_key=AST
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The galactic force law K(z
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969AJ.....74..139P&db_key=AST
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Polarimetric Observations of Nearby Stars in the Directions of the Galactic Poles and the Galactic Plane
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1968ApJ...151..907A&db_key=AST
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Three-colour photometry of early-type stars near the galactic poles
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963MNRAS.127...83W&db_key=AST
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Mikrometermessungen von Doppelsternen. III
Not Available
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Micrometer Measures of Double Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1961ApJS....6....1K&db_key=AST
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Spectral Classification of 533 B8-A2 Stars and the Mean Absolute Magnitude of a0 V Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1959ApJ...130..159O&db_key=AST
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The visual magnitudes of double stars.
Not Available
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Mesures d'étoiles doubles faites à l'Observatoire de Paris
Not Available
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INHABITED SKY
