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 Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin iThis 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 Quantitative Near-Infrared Spectroscopy of OF and WNL StarsFrom new high signal-to-noise ratio (S/N) 1-2.2 μm spectroscopy ofnine extreme early-type stars-including O Iaf, O Iafpe and WN9 types-wedetermine stellar parameters from detailed atmospheric analysis andevaluate results from near-IR analogues of well-known spectraldiagnostics in the optical. We conclude that accurate stellar parameterscan be measured from near-IR spectroscopy alone, an analysis techniqueimportant to studies of luminous stars in the Galactic center and othergalaxies. Derived stellar parameters-mass-loss rates, luminosities,surface abundances, temperatures-show good agreement between optical andnear-IR analyses, provided that IR data are of sufficient spectralresolution (R>2000) and S/N (S/N>30). Wind velocities derived fromHe I 1.0830 μm are consistent with those from ultraviolet P Cygniprofiles. Temperatures 200-1300 K systematically lower are determinedfrom the near-IR diagnostics, a difference not significant indetermining the stellar properties of these objects; which set ofspectral lines provides the more accurate physical parameters-optical orIR-cannot at present be ascertained. The strength of He I 2.0581 μmis very sensitive to the extreme ultraviolet energy distribution whereline blanketing by heavy elements plays an important role; this lineshould not on its own be considered a reliable temperature diagnostic.The three peculiar, extreme emission-line stars-the O Iafpe stars HD152386, HD 152408, and HDE 313846-are more similar in both morphologicaland physical characteristics to WNL-type Wolf-Rayet stars than to normalO Iaf supergiants and should be classified as W-R. Their classificationshould be WN9ha, in which they remain a unique subgroup. Mapping the contours of the Local bubble: preliminary resultsWe present preliminary results from a long-term program of mapping theneutral absorption characteristics of the local interstellar medium,taking advantage of Hipparcos stellar distances. Equivalent widths ofthe NaI D-line doublet at 5890 Å are presented for thelines-of-sight towards some 143 new target stars lying within 300 pc ofthe Sun. Using these data which were obtained at the Observatoire deHaute Provence, together with previously published NaI absorptionmeasurements towards a further 313 nearby targets, we present absorptionmaps of the distribution of neutral gas in the local interstellar mediumas viewed from 3 different galactic projections. In particular, thesemaps reveal the Local Bubble region as a low neutral densityinterstellar cavity in the galactic plane with radii between 65-250 pcthat is surrounded by a (dense) neutral gas boundary (or wall''). Wehave compared our iso-column contours with the contours derived bySnowden et al. (\cite{snowden98}) using ROSAT soft X-ray emission data.Consistency in the global dimensions derived for both sets of contoursis found for the case of a million degree hot LB plasma of emissivity0.0023 cm(-6) pc with an electron density of 0.005 cm(-2) . We havedetected only one relatively dense accumulation of cold, neutral gaswithin 60 pc of the Sun that surrounds the star delta Cyg, and note thatthe nearest molecular cloud complex of MBM 12 probably resides at thevery edge of the Local Bubble at a distance of ~ 90 pc. Our observationsmay also explain the very different physical properties of the columnsof interstellar gas in the line-of-sight to the two hot stars epsilonCMa and beta CMa as being due to their locations with respect to theBubble contours. Finally, in the meridian plane the LB cavity is foundto be elongated perpendicularly to the Gould's Belt plane, possiblybeing squeezed'' by the expanding shells of the Sco-Cen andPerseus-Taurus OB associations. Tables 1 and 2 are also available inelectronic form at the CDS (Strasbourg) via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html MSC - a catalogue of physical multiple starsThe MSC catalogue contains data on 612 physical multiple stars ofmultiplicity 3 to 7 which are hierarchical with few exceptions. Orbitalperiods, angular separations and mass ratios are estimated for eachsub-system. Orbital elements are given when available. The catalogue canbe accessed through CDS (Strasbourg). Half of the systems are within 100pc from the Sun. The comparison of the periods of close and widesub-systems reveals that there is no preferred period ratio and allpossible combinations of periods are found. The distribution of thelogarithms of short periods is bimodal, probably due to observationalselection. In 82\% of triple stars the close sub-system is related tothe primary of a wide pair. However, the analysis of mass ratiodistribution gives some support to the idea that component masses areindependently selected from the Salpeter mass function. Orbits of wideand close sub-systems are not always coplanar, although thecorresponding orbital angular momentum vectors do show a weak tendencyof alignment. Some observational programs based on the MSC aresuggested. Tables 2 and 3 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html UvbyHbeta_ photometry of main sequence A type stars.We present Stroemgren uvby and Hbeta_ photometry for a set of575 northern main sequence A type stars, most of them belonging to theHipparcos Input Catalogue, with V from 5mag to 10mag and with knownradial velocities. These observations enlarge the catalogue we began tocompile some years ago to more than 1500 stars. Our catalogue includeskinematic and astrophysical data for each star. Our future goal is toperform an accurate analysis of the kinematical behaviour of these starsin the solar neighbourhood. The Relation between Rotational Velocities and Spectral Peculiarities among A-Type StarsAbstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJS...99..135A&db_key=AST Ca II H and K Filter Photometry on the UVBY System. II. The Catalog of ObservationsAbstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995AJ....109.2828T&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. Near-infrared line imaging of NGC 6240 - Collision shock and nuclear starburstHigh-resolution images of H2 v = 1 - 0 S(1) and forbidden Fe II 1.64micron emission in the luminous IR galaxy NGC 6240 are presentedtogether with velocity-resolved spectra of these lines. The luminousnear-IR H2 emission observed near the nucleus is generated in a shockresulting from the merging or collision of two gas-rich disk galaxies.High-velocity wings of the H2 line profile show the presence of shockedH2 at high velocities. It is concluded that the high-velocity H2emission originates in material entrained in and shocked by a'superwind' created in a nuclear starburst. The forbidden Fe II emissionclosely follows the stellar light and radio continuum emission from thenuclei and originates in fast shocks produced by SNR resulting from astarburst in the nuclei of NGC 6240. The total SN rate in NGC 6240 isestimated to be about 2/yr based on the nonthermal radio continuumemission. The low Br-gamma flux from the galaxy indicates that thenuclei are deficient in stars more massive than about 25 solar masses. Photographic measurements of visual binariesThe results of 164 photographic measurements of 50 large and, generally,neglected visual double stars are presented. The measurements have beenmade at Brera-Merate Observatory during the years 1984-88 with Zenastrograph. Maximum separations among cataloged binariesThe paper classifies many of the widest common-motion binaries listed inthe Aitken catalog and list 72 physical pairs with known photoelectricphotometry, 31 physical pairs without good photometry, and 27 opticalpairs. As a function of primary types, the physical systems have upperlimits to their separations that are exceeded by some of the opticalpairs. The fact that optical pairs occur with larger separations impliesthat the limits are real ones and not just catalog limitations. Thoselimits (in AU) are expressed by 2500 M1 exp 1.54 for B5-KO main-sequenceprimaries. The same limits hold for the Trapezium and hierarchicalsystems studied previously. The early A type stars - Refined MK classification, confrontation with Stroemgren photometry, and the effects of rotationThe MK classification system for the early A-type stars is refined, anda parallel system of standards for the broad-lined stars is introduced.With this improved system, stars may be classified with significantlygreater precision than before. It is shown that spectral types in thissystem are not systematically affected by rotational line broadening. Atotal of 372 early A-type stars are classified, and a confrontation ofthese spectral types with Stroemgren photometry reveals a number ofsystematic photometric effects of rotation. In particular, high v sin istars are systematically redder than low v sin i stars of the samespectral type, and the beta index is weakened by rotation. It isconcluded that precise spectral classification in conjunction withStroemgren and H-beta photometry can potentially provide a valuablecheck and input to the theory of the atmospheres of rotating stars. ICCD speckle observations of binary stars. I - A survey for duplicity among the bright starsA survey of a sample of 672 stars from the Yale Bright Star Catalog(Hoffleit, 1982) has been carried out using speckle interferometry onthe 3.6-cm Canada-France-Hawaii Telescope in order to establish thebinary star frequency within the sample. This effort was motivated bythe need for a more observationally determined basis for predicting thefrequency of failure of the Hubble Space Telescope (HST) fine-guidancesensors to achieve guide-star lock due to duplicity. This survey of 426dwarfs and 246 evolved stars yielded measurements of 52 newly discoveredbinaries and 60 previously known binary systems. It is shown that thefrequency of close visual binaries in the separation range 0.04-0.25arcsec is 11 percent, or nearly 3.5 times that previously known. Carbon abundances and meridional mixing in rapidly rotating early-A starsCarbon abundances are obtained from lines of C I at 9100 A for 22early-A main-sequence stars with projected rotational velocities of upto 180 km/s. The abundance shows no significant trend with increasingrotation. A preliminary conclusion is that meridional mixing currents donot bring CN-processed material into the atmospheres of these rotating Astars. Several carbon deficient stars are tentatively identified aschemically peculiar A stars. Future surveys should cover a sufficientwavelength interval to permit a spectral classification and adetermination of the microturbulence. Visual multiples. VIII - 1000 MK typesA total of 1000 new classifications are given for stars brighter than B= 8.0 mag in the Aitken double star catalog. The classificationssupplement 865 classifications obtained in 1981 and 1984. Among thenewly discovered stars are 12 new Ap stars, eight Lambda Bootis stars,one Ba II star, and 60 Am stars. A detailed list of the newclassifications is given. The local system of early type stars - Spatial extent and kinematicsPublished uvby and H-beta photometric data and proper motions arecompiled and analyzed to characterize the structure and kinematics ofthe bright early-type O-A0 stars in the solar vicinity, with a focus onthe Gould belt. The selection and calibration techniques are explained,and the data are presented in extensive tables and graphs and discussedin detail. The Gould belt stars of age less than 20 Myr are shown togive belt inclination 19 deg to the Galactic plane and node-lineorientation in the direction of Galactic rotation, while the symmetricaldistribution about the Galactic plane and kinematic properties (purecircular differential rotation) of the belt stars over 60 Myr oldresemble those of fainter nonbelt stars of all ages. The unresolveddiscrepancy between the expansion observed in the youngest nearby starsand the predictions of simple models of expansion from a point isattributed to the inhomogeneous distribution of interstellar matter. The A0 starsA photometric grid, standardized on MK spectral standards, has been usedto compare spectral types and luminosity classes obtainedphotometrically with those in two extensive spectral surveys coveringthe entire sky. Major discrepancies include the spectroscopicclassification of B9.5, which may indicate an otherwise unrecognizedspectral peculiarity, a different A0/A1 spectral type boundary in thetwo samples involved, the well-known misclassification of weak heliumstars, and an appreciable percentage of stars which are called dwarfsspectroscopically but are of higher photometric luminosity. The spacemotion vectors of these stars for which radial velocities are available,and excluding the minimum of 25 percent that are spectroscopic binarieswithout orbital elements, show structure in their distribution in the(U, V)-plane, with members of the Local Association and the Hyades andSirius superclusters forming obvious concentrations. The members of theLocal Association in the samples are mainly old (more than 200 millionyears) mode A stars, although a few much younger stars are included. Themembers of the Hyades and Sirius superclusters contain many bluestragglers, including several peculiar stars of the Hg, Mn, and Sivarieties. Ages and uvbybeta photometry of wide visual binaries. IIVisual magnitudes and color indices b-y, m1, c1 and beta have beenobtained for the members of 39 double or multiple systems containingstars with magnitudes greater than 4m. Relationships between stellarages, spectral types and photometric indices are given from a sample ofabout 3,500 stars. Data is presented with regard to MK spectral types,the separation, and absolute magnitudes; also tabulated are the meanvalues of photometric unreddened indices with their standard deviationfor intervals of 0.2 in log age. From calculations for each binary ofthe relative difference in the ages of the components and the differencein the effective temperatures, an increase in the relative differencesin ages with the differences in temperatures is noted. About the Consistency of Absolute Luminosity CalibrationsAbstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&A....82..370H&db_key=AST UVBY Bet study of A-and F-type visual binaries. II.Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978AJ.....83.1646M&db_key=AST UVBY photometry of wide visual double stars with B, A and F spectral type- I.Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978A&AS...34..453O&db_key=AST Photoelectric H-alpha line photometry of early-type starsA total of 293 bright stars of spectral types O, B, A, F and ofluminosity classes I through V have been measured with a photoelectricphotometer equipped with two interference filters of 30-A bandwidth, onecentered on H-alpha and the other at 6622 A. A correction term has beenallowed for the response of the photometric system and for the continuumenergy distribution in the two spectral regions considered. Theresulting photometric alpha indices of H-alpha line strength arecompared with previous H-alpha, H-beta, and H-gamma photometricmeasures, H-alpha equivalent widths, the MK spectral type, /u-b/, /c1/,and b-y indices of the uvby photometric system. The results emphasizethe advantage of using H-alpha line photometry to discriminate betweenemission-line effects and luminosity effects in early-type stars and todetect emission-line variability. The proper motions of Struve double starsThe proper motions of the components of 103 Struve double stars fromMuller's list of neglected stars and of 15 other systems were measuredrelative to sets of reference stars, for the primary purpose ofdistinguishing physical from optical pairs. A by-product of thisinvestigation is a list of measured position angles and distances ofthese objects, at two epochs each. Rotational velocities and spectral types for a sample of binary systems.Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975A&AS...19...91L&db_key=AST Rotational Velocities of a0 StarsAbstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974ApJS...28..101D&db_key=AST Four-colour and H BET photometry of some bright southern stars- II.Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972MNRAS.160..155S&db_key=AST Statistical Studies in Stellar Rotation. II. a Method of Analyzing Rotational Coupling in Double Stars and an Introduction to its ApplicationsAbstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972ApJ...177..161B&db_key=AST Four-color and Hβ photometry for the brighter AO type starsAbstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972A&AS....5..109C&db_key=AST A catalogue of proper motions for 437 A starsAbstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970A&AS....1..189F&db_key=AST Photoelectric observations of early A starsAbstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970A&AS....1..165J&db_key=AST
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 Constellation: Hercules Right ascension: 16h40m38.70s Declination: +04Â°13'11.0" Apparent magnitude: 5.77 Distance: 92.937 parsecs Proper motion RA: -0.1 Proper motion Dec: -9.9 B-T magnitude: 5.751 V-T magnitude: 5.759

Catalogs and designations:
 Proper Names (Edit) Flamsteed 37 Her HD 1989 HD 150378 TYCHO-2 2000 TYC 391-2824-1 USNO-A2.0 USNO-A2 0900-08852461 BSC 1991 HR 6195 HIP HIP 81641 → Request more catalogs and designations from VizieR