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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Speckle Interferometry of New and Problem Hipparcos Binaries. II. Observations Obtained in 1998-1999 from McDonald Observatory
The Hipparcos satellite made measurements of over 9734 known doublestars, 3406 new double stars, and 11,687 unresolved but possible doublestars. The high angular resolution afforded by speckle interferometrymakes it an efficient means to confirm these systems from the ground,which were first discovered from space. Because of its coverage of adifferent region of angular separation-magnitude difference(ρ-Δm) space, speckle interferometry also holds promise toascertain the duplicity of the unresolved Hipparcos ``problem'' stars.Presented are observations of 116 new Hipparcos double stars and 469Hipparcos ``problem stars,'' as well as 238 measures of other doublestars and 246 other high-quality nondetections. Included in these areobservations of double stars listed in the Tycho-2 Catalogue andpossible grid stars for the Space Interferometry Mission.
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Speckle Interferometry at the US Naval Observatory. VI.
The results of 1068 speckle interferometric observations of doublestars, made with the 26 inch (0.66 m) refractor of the US NavalObservatory, are presented. These observations are averaged into 841means of 815 binary stars. The systems range in separation from 0.22" to6.01" with a mean separation of 2.21" and have a limiting secondarymagnitude of V=12.5. This is the sixth in a series of papers presentingmeasures obtained with this system, and it covers the period 1999January 1 through 2000 January 9.
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ICCD Speckle Observations of Binary Stars. XXIII. Measurements during 1982-1997 from Six Telescopes, with 14 New Orbits
We present 2017 observations of 1286 binary stars, observed by means ofspeckle interferometry using six telescopes over a 15 year period from1982 April to 1997 June. These measurements constitute the 23dinstallment in CHARA's speckle program at 2 to 4 m class telescopes andinclude the second major collection of measurements from the MountWilson 100 inch (2.5 m) Hooker Telescope. Orbital elements are alsopresented for 14 systems, seven of which have had no previouslypublished orbital analyses.
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Two-colour photometry for 9473 components of close Hipparcos double and multiple stars
Using observations obtained with the Tycho instrument of the ESAHipparcos satellite, a two-colour photometry is produced for componentsof more than 7 000 Hipparcos double and multiple stars with angularseparations 0.1 to 2.5 arcsec. We publish 9473 components of 5173systems with separations above 0.3 arcsec. The majority of them did nothave Tycho photometry in the Hipparcos catalogue. The magnitudes arederived in the Tycho B_T and V_T passbands, similar to the Johnsonpassbands. Photometrically resolved components of the binaries withstatistically significant trigonometric parallaxes can be put on an HRdiagram, the majority of them for the first time. Based on observationsmade with the ESA Hipparcos satellite.
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Near-Infrared Line Observations of Arp 299 as a Tracer of Activity in the Nuclei
We have obtained images of the molecular hydrogen (H2) andBrγ emission lines in the interacting galaxy system Arp 299. Inorder to investigate the nuclear activities, we also have obtained H-and K-band spectra for three of its 2 μm continuum peaks and alsoJ-band spectra for one of them. From the line ratios of Paγ,Paβ, Br10, and Brγ, and also those between [Fe II] 1.26 μmand [Fe II] 1.64 μm, we have successfully modeled the extinction forcomponent A as a combination of AK=2.6 mag region(s) andAK=0.3 mag region(s). The extinction corrected Brγluminosity requires 5x1054 s-1 of Lyman photons,which corresponds to 3x105 ``O6 stars.'' The mean stellardensity within its 100 pc core is comparable to those for the cores inblue compact dwarf galaxies even though the luminosity is almost 2orders of magnitude larger. The starbursts at the nucleus of component Aare probably the most dominant source for the far-infrared emission fromthis component. In this component, we have found large [Fe II]/H Iratios, which are at the higher end of starburst galaxies and aretypical for AGNs or AGN/starburst composites. The nucleus must be in astarburst phase that includes many supernova remnants. The spatialdistribution of the H2 emission for this interacting systemis similar to that of the 12CO 1-0 emission mapped by Aaltoet al. The H2 intensity, however, is not proportional to theCO intensity among components, because of the difference in theH2 excitation mechanism among them. We report the firstpossible detection of J-band H2 lines in infrared luminousgalaxies in component A, which suggests a significant contribution ofnonthermal excitation mechanisms.
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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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Dust Extinction in Starburst Galaxies - NGC1614 and NGC7714
We present high signal-to-noise ratio observations of the near- infraredhydrogen recombination fines Paβ, Brβ and Brα in thegalaxies NGC 1614 and 7714. The data are used in conjunction withexisting optical line fluxes to examine the dust extinction towards thestar-forming nuclei of these galaxies. In the case of NGC 1614, atleast, the conventional model of a foreground absorbing screen is foundto be incorrect, resulting in an underestimate of the true extinction.
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UBV photometry of stars whose positions are accurately known. VI
Results are presented from UBV photometric observations of 1000 stars ofthe Bright Star Catalogue and the faint extension of the FK5.Observations were carried out between July 1987 and December 1990 withthe 40-cm Cassegrain telescope of the Kvistaberg Observatory.
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Binary star measurements made at Nice with the 50-cm reflector
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1989A&AS...77..125L&db_key=AST
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Photometric parallaxes for selected stars of color class M from the NLTT catalog. II - The declination zone 0 deg to +20 deg
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1986AJ.....91..626W&db_key=AST
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Micrometric observations of visual double stars
A new program of visual double-star observations obtained during theperiod from May 26, 1982 to Feb. 24, 1983 at the Torino AstronomicalObservatory is discussed. A list concerning 480 micrometric measurementsof 149 pairs is reported. For orbital double stars, a comparison withthe orbits reported by Muller and Couteau (1979) is given.
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Double star observations made with the 28-inch refractor 1963-1970.
Not Available
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Double star measures at Lick Observatory, Mount Hamilton, California.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978PASP...90..465H&db_key=AST
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Micrometer observations of double stars.8.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975ApJS...29..315H&db_key=AST
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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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Mesures d'étoiles doubles à Meudon
Not Available
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Mikrometermessungen von Doppelsternen. V
Not Available
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Mikrometermessungen von Doppelsternen. V.
Not Available
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Mesures d'étoiles doubles faites aux Observatoires Yerkes et McDonald
Not Available
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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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Mesures d'étoiles doubles faites au réfracteur de 38 cm de l'Observatoire de Nice
Not Available
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Micrometer Measures of Double Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1959ApJS....4...45V&db_key=AST
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Measures of 266 double stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1957AJ.....62..153W&db_key=AST
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Mesures d'étoiles doubles faites au réfracteur de 38 centimètres de l'Observatoire de Nice
Not Available
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Mesures micrométriques d'étoiles doubles (suite)
Not Available
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INHABITED SKY
