An optical velocity for the Phoenix dwarf galaxy
We present the results of a Very Large Telescope observing programmecarried out in service mode using FORS1 on ANTU in long-slit mode todetermine the optical velocities of nearby low surface brightnessgalaxies. As part of our programme of service observations we obtainedlong-slit spectra of several members of the Phoenix dwarf galaxy fromwhich we derive an optical heliocentric radial velocity of -13 +/- 9 kms-1. This agrees very well with the velocity of the mostpromising of the H I clouds seen around Phoenix, which has aheliocentric velocity of -23 km s-1, but is significantlydifferent from the recently published optical heliocentric velocity ofPhoenix of -52 +/- 6km s-1 by Gallart et al.
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Stellar populations in Seyfert 2 galaxies. I. Atlas of near-UV spectra
We have carried out a uniform spectroscopic survey of Seyfert 2 galaxiesto study the stellar populations of the host galaxies. New spectra havebeen obtained for 79 Southern galaxies classified as Seyfert 2 galaxies,7 normal galaxies, and 73 stars at a resolution of 2.2 Å over thewavelength region 3500-5300 Å. Cross-correlation between thestellar spectra is performed to group the individual observations into44 synthesis standard spectra. The standard groups include a solarabundance sequence of spectral types from O5 to M3 for dwarfs, giants,and supergiants. Metal-rich and metal-weak F-K giants and dwarfs arealso included. A comparison of the stellar data with previouslypublished spectra is performed both with the individual spectra and thestandard groups. For each galaxy, two distinct spatial regions areconsidered: the nucleus and the external bulge. Spectroscopic variationsfrom one galaxy to another and from the central to the external regionare briefly discussed. It is found that the central region of a Seyfert2 galaxy, after subtracting the bulge stellar population, always shows anear-UV spectrum similar to one of three representative categories: a)many strong emission lines and only two visible absorption lines (Ca IiK and G band) (Sey2e); b) few emission lines, many absorption lines, anda redder continuum than the previous category (Sey2a); c) an almost flatcontinuum and high-order Balmer lines seen in absorption (Sey2b). Theproportion of Seyfert 2 galaxies belonging to each class is found to be22%, 28%, and 50% respectively. We find no significative differencesbetween morphology distributions of Seyfert 2 galaxies with Balmer linesdetected in absorption and the rest of the sample. This quick lookthrough the atlas indicates that half of Seyfert 2 galaxies harbour ayoung stellar population (about or less than 100 Myr) in their centralregion, clearly unveiled by the high order Balmer series seen inabsorption. Based on observations collected at the European SouthernObservatory, Chile (ESO 65.P-0014(A)). Tables 1-3 and 8 and Fig. A.1(Appendix A) are only available in electronic form athttp://www.edpsciences.org
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The optical velocity of the Antlia dwarf galaxy
We present the results of a Very Large Telescope observing programmecarried out in service mode using fors1 on ANTU (UT1) in long slit modeto determine the optical velocities of nearby low surface brightnessgalaxies. Outlying Local Group galaxies are of paramount importance inplacing constraints on the dynamics and thus on both the age and thetotal mass of the Local Group. Optical velocities are also necessary todetermine if the observations of Hi gas in and around these systems arethe result of gas associated with these galaxies or a chancesuperposition with high-velocity Hi clouds or the Magellanic Stream. Thedata were of a sufficient signal-to-noise ration to enable us to obtaina reliable result in one of the galaxies we observed - Antlia - forwhich we have found an optical heliocentric radial velocity of351+/-15kms-1.
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A catalog of rotational and radial velocities for evolved stars
Rotational and radial velocities have been measured for about 2000evolved stars of luminosity classes IV, III, II and Ib covering thespectral region F, G and K. The survey was carried out with the CORAVELspectrometer. The precision for the radial velocities is better than0.30 km s-1, whereas for the rotational velocity measurementsthe uncertainties are typically 1.0 km s-1 for subgiants andgiants and 2.0 km s-1 for class II giants and Ib supergiants.These data will add constraints to studies of the rotational behaviourof evolved stars as well as solid informations concerning the presenceof external rotational brakes, tidal interactions in evolved binarysystems and on the link between rotation, chemical abundance and stellaractivity. In this paper we present the rotational velocity v sin i andthe mean radial velocity for the stars of luminosity classes IV, III andII. Based on observations collected at the Haute--Provence Observatory,Saint--Michel, France and at the European Southern Observatory, LaSilla, Chile. Table \ref{tab5} also available in electronic form at CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Radial velocities. Measurements of 2800 B2-F5 stars for HIPPARCOS
Radial velocities have been determined for a sample of 2930 B2-F5 stars,95% observed by the Hipparcos satellite in the north hemisphere and 80%without reliable radial velocity up to now. Observations were obtainedat the Observatoire de Haute Provence with a dispersion of 80Ä,mm(-1) with the aim of studying stellar and galactic dynamics.Radial velocities have been measured by correlation with templates ofthe same spectral class. The mean obtained precision is 3.0 km s(-1)with three observations. A new MK spectral classification is estimatedfor all stars. Based on observations made at the Haute ProvenceObservatory, France and on data from The Hipparcos Catalogue, ESA.Tables 4, 5 and 6 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr or viahttp://cdsweb.u-strasbg.fr/Abstract.htm
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Lithium in population I subgiants
We present a lithium survey for a sample of 91 Pop. I stars. JHKLphotometry was also obtained for 61 stars in the sample. Besides Liabundances, [Fe/H] values were derived. Thanks to Hipparcos parallaxes,we could infer absolute V magnitudes for our sample stars and were ableto place them on the color-magnitude diagram, which allowed us toconstrain their evolutionary status. Masses and ages were derived formost of the stars by comparison with evolutionary tracks. The sample wasoriginally selected so to include class IV stars later thanspectral-type F0, but, based on the location on the color-magnitudediagram, we found a posteriori that a fraction of the stars (about 20%)are either main sequence stars or evolved giants. As it is the case fordwarfs and giants, a large spread in lithium abundance is present amongthe subgiants in our sample. As expected, the average lithium decreasesas the stars evolve along the subgiant branch; however, there is not aone-to-one relationship between the position on the color-magnitudediagram and lithium abundance, and the observed dispersion is onlypartially explainable as due to a dispersion in mass, metallicity, andage. In particular, a dispersion in lithium is seen among slightlyevolved subgiants with masses close to solar but in the sameevolutionary stage as the G2 IV star beta Hyi. The comparison of thebeta Hyi-like sample with a sample of non evolved solar-like starsindeed suggests that beta Hyi has most likely evolved from a mainsequence Li-rich star, rather than from a Li-poor star (like the Sun)that has dredged-up previously stored lithium. Our sample includesseveral stars that have completed the first-dredge up lithium dilution,but that have not yet evolved to the evolutionary point whereextra-mixing in the giant phase is thought to occur. A large number ofthem have Li abundances considerably below the theoretical predictionsof first dredge-up dilution. We confirm that this is due to the factthat the progenitors of these stars are most likely stars that havedepleted lithium while on the main sequence; the fraction of post-dredgeup Li rich/poor stars, in fact, is consistent with the observeddistribution of Li abundances among stars that have just left the mainsequence. The signature of the second mixing (or RGB extra-mixing)episode is evident in the log n(Li) vs. B-V and log n(Li) vs. M_boldistributions of the stars in the sample; it seems however that theextra-mixing occurs at luminosities lower than predicted by the modelsof Charbonnel (1994). Finally, a few evolved giants are found thatshould have passed the second mixing episode, but that do not show signsof it. At least half of them are spectroscopic binaries. Based onobservations carried out at the European Southern Observatory, La Silla,Chile
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Spectroscopy of the optical Einstein ring 0047-2808
We present optical and near-infrared spectroscopic observations of theoptical Einstein ring 0047-2808. We detect both [O III] lineslambdalambda4959, 5007 near ~2.3mum, confirming the redshift of thelensed source as z=3.595. The Lyalpha line is redshifted relative to the[O III] line by 140+/-20kms^-1. Similar velocity shifts have been seenin nearby starburst galaxies. The [O III] line is very narrow, 130kms^-1FWHM. If the ring is the image of the centre of a galaxy, theone-dimensional stellar velocity dispersion sigma=55kms^-1 isconsiderably smaller than the value predicted by Baugh et al. for thesomewhat brighter Lyman-break galaxies. The Lyalpha line issignificantly broader than the [O III] line, probably due to resonantscattering. The stellar central velocity dispersion of the early-typedeflector galaxy at z=0.485 is 250+/-30kms^-1. This value is in goodagreement both with the value predicted from the radius of the Einsteinring (and a singular isothermal sphere model for the deflector), andwith the value estimated from the D_n-sigma relation.
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Photoelectric Photometry of Stars in the Orion Standard Region
Magnitudes and color indices in the Vilnius seven-color photometricsystem are given for 108 stars in the Orion standard region around theOrion Belt and the star lambda Orionis. New spectral and luminosityclasses, estimated from the photometric data, are given for some of thestars.
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Ca II H and K Filter Photometry on the UVBY System. II. The Catalog of Observations
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995AJ....109.2828T&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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The photometric variability of K giants
We have photometrically monitored 49 of the more than 200 K giants inthe Yale Catalog of Bright Stars (YCBS) which are named or suspectedvariable stars. Only two (HR 3275 and HR 5219) are clearly variable; afew more program stars and K- and M-giant comparison stars aremarginally variable. Most of these appear to be RS Canum Venaticorum orSR variables.
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Kinematics in the Outer Parts of the Small Magellanic Cloud
Extensive studies of red horizontal branch (clump) stars in the outerparts of the Small Magellanic Cloud (SMC) have suggested the presence ofa large line-of-sight depth in the north-eastern region. A sample of redhorizontal branch stars in the area of maximum depth was observed in1989 December and 1990 December with the multi-object spectroscopicfacility Autofib at the 3.9-m Anglo-Australian Telescope, with thepurpose of deriving the velocity distribution for these stars. The datashow a well- defined correlation between distance along the line ofsight and radial velocity (corresponding to 8 km s^-1^ kpc^-1^), whichmay be interpreted as the result of the tidal interaction between theSMC and the LMC.
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Optical Polarization of 1000 Stars Within 50-PARSECS from the Sun
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993A&AS..101..551L&db_key=AST
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A Polarimetric Investigation on Interstellar Dust Within 50-PARSECS from the Sun
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993A&A...274..203L&db_key=AST
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Radial velocities of 26 northern Milky Way Cepheids
Spectra taken with the Palomar 60 inch echelle spectrograph are used toobtain 231 radial velocity measurements of 26 northern hemisphere MilkyWay Cepheids with latitude between 15 and 140 deg and b below 5 deg. Thetypical accuracy of the Cepheid velocities is 0.8 km/s. Radialvelocities of standard stars with accuracies of 0.6 km/s are alsoreported, and zero points determined from several systems are compared.The adopted zero point agrees with those of several other systems to +or - 0.1 km/s.
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Large and kinematically unbiased samples of G- and K-type stars. II - Observations of evolved stars in the Bright Star sample. III - Evolved young disk stars in the Bright Star sample
Four color and RI observations were obtained for a large sample ofG-type and K-type stars in the Bright Star Catalogue. Data are firstpresented for 110 evolved stars. Photometry of evolved young diskpopulation stars have then been calibrated for luminosity, reddening,and metallicity on the basis of results for members of the Hyades andSirius superclusters. New DDO results are given for 120 stars.
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The stellar dynamics of NGC 1399
The dynamical properties of NGC 1399 as revealed through new CCD surfacephotometry and measurements of the velocity dispersion profile out toalmost 6 kpc are considered. The data reveal no unusual features in thesurface brightness profile of this galaxy, but the velocity dispersionprofile is quite striking. It is approximately constant through theregion 10-86 arcsec from the core but within 10 arcsec increasessignificantly from about 200 km/s to a central value of 365 km/s.Alternative interpretations of the velocity dispersion data involvingeither anisotropic stellar orbits or a black hole are considered. It isconcluded that a black hole in NGC 1399 is unlikely and that mildanisotropy in the stellar distribution is adequate to explain the data.
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The dynamics of rich clusters. I - Velocity data
Using the fiber-optic spectroscopy facility at the Anglo-AustralianTelescope and the Automated Photographic Measuring machine at theInstitute of Astronomy, Cambridge, 604 radial velocities and 501 stellarvelocity dispersions for 40 galaxies in fields centered on 14 richclusters from the southern cluster survey of Abell and Corwin (1983) arepresented. The homogeneity of the data and the variety (in richness andmorphological type) of the clusters are intended to facilitateintercomparisons of dynamical situations and the isolation of commonphenomena. Good agreement is found with previous results.
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Three-dimensional structure in field 349 of the southern sky survey. I - Redshifts for a magnitude-limited sample of galaxies from slit spectra
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1986MNRAS.220..901P&db_key=AST
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E. W. Fick Observatory stellar radial velocity measurements. I - 1976-1984
Stellar radial velocity observations made with the large vacuumhigh-dispersion photoelectric radial velocity spectrometer at FickObservatory are reported. This includes nearly 2000 late-type starsobserved during 585 nights. Gradual modifications to this instrumentover its first eight years of operation have reduced the observationalerror for high-quality dip observations to + or - 0.8 km/s.
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An analysis of the radial-velocity performance of the image-tube spectrograph on the CTIO 1-meter telescope
An analysis of the radial-velocity performance of the 120 A/mmconfiguration of the image-tube spectrograph on the CTIO/Yale 1-metertelescope is presented. The instrument is found to be stable within agiven run but to be susceptible to small changes from run to run. Theremay be systematic changes in velocity residual with declination; noneare found with zenith angle or hour angle. A typical precision of plusor minus 10 km/sec for a single spectrum of a Population I star isachieved for the spectrograph configuration. Rest wavelengths derivedfor F0-K4 Population I stars observed with this spectrograph/image-tubeconfiguration are presented. A table of radial velocities and residualsfor IAU radial-velocity standard stars, as well as some other brightstars, is also presented.
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The zero-point of the 'Fick' radial-velocity stars
The radial velocities determined for 61 stars by Beavers et al. (1979)using the spectrometer developed at Fick Observatory are compared withthose derived from observations obtained using the coude-feedspectrograph at KPNO over the spectral range from F8 through K4 during1978-1981. The stellar effective wavelengths used in analyzing the KPNOobservations are established using observations of solar-system objects.The data are presented in tables, and the difference between the Fickand KPNO radial velocities is found to be 0.0 + or - 0.1 km/s, comparedto 0.4 + or - 0.5 km/s for a group of IAU standard objects also checkedat KPNO. These low differences confirm the accuracy of the Fick and IAUzero points.
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Observations of Standard Velocity Stars
Not Available
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Kinematics of elliptical-like galaxies with dust lanes
Spectroscopic observations have been made of four elliptical-likegalaxies which contain strong dust lanes. Stellar rotation curves andvelocity dispersion profiles are presented in at least two positionangles for each galaxy. Spectra taken along the dust lanes also exhibitweak emission lines from which the velocity field of the ionized gas hasbeen determined. In two cases the rotation axes of the stellar andgaseous components are orthogonal. A comparison is made with publishedmodels of tumbling prolate bars and constraints on the maximum figurerotation are derived. The nature of the present sample is brieflydiscussed in the light of these new observations.
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Standard Velocity Stars
Not Available
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Radial velocities of IAU standard stars
Radial velocities of 52 IAU Radial Velocity Standard stars, obtainedfrom 358 spectra of 12 and 20 A/mm dispersion during the 1970-1978period, are presented. Some discrepancies between the present resultsand those of the IAU are discussed.
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On the spectrographic and photometric data for the brightest stars in the Small Magellanic Cloud
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1979A&A....77..269A&db_key=AST
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The stellar aggregate surrounding HD 101205 (IC 2944).
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&A....54..233A&db_key=AST
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Optical polarization of stars of galactic latitudes b-45 degres.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976A&AS...23..125S&db_key=AST
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Radial velocities of supergiants in the Small Magellanic Cloud
This paper presents the kinematic results of a study, comparing SmallMagellanic Cloud supergiants to galactic supergiants. The stars werechosen from the lists of Florsch (1972a) and Sanduleak (1968). A roughcorrelation is found between the radial velocities of the supergiantsand the radial velocities of neutral hydrogen. In some cases a betterrelation exists with the radial velocities of the H II regions.
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NEWS@SKY (Science&Space News)
