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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
| K-Band Spectroscopy of Luminous Young Stellar Objects
We present spectroscopy from 2.0 to 2.33 μm of 32 luminous youngstellar objects (YSOs), which are presumed to be precursors of HerbigAe/Be stars. From these stars, Brγ, H2, CO, He I, andFe II were found in emission with detection rates of 97%, 34%, 22%, 9%,and 3%, respectively. We compare the spectral features with those ofHerbig Ae/Be stars in the literature to investigate the spectralbehavior of intermediate- to high-mass YSOs and to search for theirrelations to the spectral energy distributions (SEDs). H2emission is detected only in Class I SEDs with particularly largespectral indices. The detection of H2 emission is related tothe degree of the dispersal of circumstellar envelopes, whereH2 molecules are probably excited by shocks from outflows. Onthe other hand, Brγ emission, which is generally thought to occurin stellar winds close to the stars, does not depend on the SEDs. Thisindicates that stellar wind from luminous YSOs does not change much fromthe embedded phase to the optically visible phase. CO emission is alsoindependent of the SEDs, but the detection rate is much lower than thatof Brγ emission. Probably, more specific physical conditionsregarding circumstellar disks and stellar radiation are necessary for COemission to take place.
| Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521
| 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
| 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.
| Erratum - Some Errata in the Fifth General Catalogue of MK Spectral Classifications
Not Available
| Prediction of spectral classification from photometric observations - Application of the UVBY beta photometry and the MK spectra classification. II - General case
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&A....85...93M&db_key=AST
| Prediction of spectral classification from photometric observations-application to the UVBY beta photometry and the MK spectral classification. I - Prediction assuming a luminosity class
An algorithm based on multiple stepwise and isotonic regressions isdeveloped for the prediction of spectral classification from photometricdata. The prediction assumes a luminosity class with reference touvbybeta photometry and the MK spectral classification. The precisionattained is about 90 percent and 80 percent probability of being withinone spectral subtype respectively for luminosity groups I and V and forluminosity groups III and IV. A list of stars for which discrepanciesappear between photometry and spectral classification is given.
| Stellar kinematics and evolution
Not Available
| Catalog of Indidual Radial Velocities, 0h-12h, Measured by Astronomers of the Mount Wilson Observatory
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJS...19..387A&db_key=AST
| Short-Period Variability of b, a, and F Stars. III. a Survey of Delta Scuti Variable Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969ApJS...19...79B&db_key=AST
| Abundance Homogeneity and Absolute Magnitudes of the Hyades Moving Group
Not Available
| Colors, luminosities, and motions of the nearer G-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1964AJ.....69..570E&db_key=AST
| Étude spectrophotométrique et statistique d'une région obscure dans Cassiopée
Not Available
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| Takýmyýldýz: | Zincirli Prenses |
| Sað Açýklýk: | 01h06m22.80s |
| Yükselim: | +62°45'42.0" |
| Görünürdeki Parlaklýk: | 6.54 |
| Uzaklýk: | 69.493 parsek |
| özdevim Sað Açýklýk: | 101.5 |
| özdevim Yükselim: | -33.1 |
| B-T magnitude: | 6.768 |
| V-T magnitude: | 6.549 |
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