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Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
| Stellar Kinematics of Boxy Bulges: Large-Scale Bars and Inner Disks
Long-slit stellar kinematic observations were obtained along the majoraxis of 30 edge-on spiral galaxies, 24 with a boxy or peanut-shaped(B/PS) bulge and six with other bulge types for comparison. Such B/PSbulges are identified in at least 45% of highly inclined systems, and agrowing body of theoretical and observational work suggests that theyare the edge-on projection of thickened bars. Profiles of the meanstellar velocity V, the velocity dispersion σ, as well as theasymmetric (h3) and symmetric (h4) deviations froma pure Gaussian are presented for all objects. Comparing these profileswith stellar kinematic bar diagnostics developed from N-bodysimulations, we find bar signatures in 24 of our sample galaxies (80%).Galaxies with a B/PS bulge typically show a double-humped rotation curvewith an intermediate dip or plateau. They also frequently show a ratherflat central velocity dispersion profile accompanied by a secondary peakor plateau, and numerous galaxies have a local central σ minimum(>~40%). The h3 profiles display up to three slopereversals. Most importantly, h3 is normally correlated with Vover the presumed bar length, contrary to expectations from axisymmetricdisks. These characteristic bar signatures strengthen the case for aclose relationship between B/PS bulges and bars and leave little roomfor other explanations of the bulges' shape. We also find thath3 is anticorrelated with V in the very center of mostgalaxies (>~60%), indicating that these objects additionally harborcold and dense decoupled (quasi-) axisymmetric central stellar disks,which may be related to the central light peaks. These central diskscoincide with previously identified star-forming ionized-gas disks(nuclear spirals) in gas-rich systems, and we argue that they formed outof gas accumulated by the bar at its center through inflow. As suggestedby N-body models, the asymmetry of the velocity profile (h3)appears to be a reliable tracer of asymmetries in disks, allowing us todiscriminate between axisymmetric and barred disks seen in projection.B/PS bulges (and thus a large fraction of all bulges) appear to be madeup mostly of disk material, which has acquired a large vertical extentthrough bar-driven vertical instabilities. Their formation is thusprobably dominated by secular evolution processes rather than merging.
| Studies of binary star cluster candidates in the bar of the LMC. I. SL 353 and SL 349
We present a detailed study of the cluster pair SL 353 & SL 349.This candidate binary cluster is located at the northwestern rim of theLMC bar. Based on photometric data we find that both clusters are coevalwith an age of 550+/-100 Myr. We use the Ca II triplet in the spectra ofindividual red giants to derive radial velocities. Both components ofthe binary cluster candidate show very similar mean velocities(~274+/-10 km s-1 for SL 349 and ~279+/-4 km s-1for SL 353) while the field stars show lower velocities (~240+/-19 kms-1). These findings suggest a common origin of the twoclusters from the same GMC. In this sense the cluster pair mayconstitute a true binary cluster. We furthermore investigate the stellardensities in and around the star clusters and compare them withisopleths created from artificial, interacting as well asnon-interacting star clusters. Gravitational interaction leads to adistortion which can also be found in the observed pair. Based onobservations taken at the European Southern Observatory, La Silla,Chile.
| Sixth Catalogue of Fundamental Stars (FK6). Part III. Additional fundamental stars with direct solutions
The FK6 is a suitable combination of the results of the HIPPARCOSastrometry satellite with ground-based data, measured over a longinterval of time and summarized mainly in the FK5. Part III of the FK6(abbreviated FK6(III)) contains additional fundamental stars with directsolutions. Such direct solutions are appropriate for single stars or forobjects which can be treated like single stars. Part III of the FK6contains in total 3272 stars. Their ground-based data stem from thebright extension of the FK5 (735 stars), from the catalogue of remainingSup stars (RSup, 732 stars), and from the faint extension of the FK5(1805 stars). From the 3272 stars in Part III, we have selected 1928objects as "astrometrically excellent stars", since their instantaneousproper motions and their mean (time-averaged) ones do not differsignificantly. Hence most of the astrometrically excellent stars arewell-behaving "single-star candidates" with good astrometric data. Thesestars are most suited for high-precision astrometry. On the other hand,354 of the stars in Part III are Δμ binaries in the sense ofWielen et al. (1999). Many of them are newly discovered probablebinaries with no other hitherto known indication of binarity. The FK6gives, besides the classical "single-star mode" solutions (SI mode),other solutions which take into account the fact that hidden astrometricbinaries among "apparently single-stars" introduce sizable "cosmicerrors" into the quasi-instantaneously measured HIPPARCOS proper motionsand positions. The FK6 gives, in addition to the SI mode, the "long-termprediction (LTP) mode" and the "short-term prediction (STP) mode". TheseLTP and STP modes are on average the most precise solutions forapparently single stars, depending on the epoch difference with respectto the HIPPARCOS epoch of about 1991. The typical mean error of anFK6(III) proper motion in the single-star mode is 0.59 mas/year. This isa factor of 1.34 better than the typical HIPPARCOS errors for thesestars of 0.79 mas/year. In the long-term prediction mode, in whichcosmic errors are taken into account, the FK6(III) proper motions have atypical mean error of 0.93 mas/year, which is by a factor of about 2better than the corresponding error for the HIPPARCOS values of 1.83mas/year (cosmic errors included).
| The shape and scale of Galactic rotation from Cepheid kinematics
A catalog of Cepheid variables is used to probe the kinematics of theGalactic disk. Radial velocities are measured for eight distant Cepheidstoward l = 300 deg; these new Cepheids provide a particularly goodconstraint on the distance to the Galactic center, R0. We model the diskwith both an axisymmetric rotation curve and one with a weak ellipticalcomponent, and find evidence for an ellipticity of 0.043 +/- 0.016 nearthe sun. Using these models, we derive R0 = 7.66 +/- 0.32 kpc andv(circ) = 237 +/- 12 km/s. The distance to the Galactic center agreeswell with recent determinations from the distribution of RR Lyraevariables and disfavors most models with large ellipticities at thesolar orbit.
| A radial velocity study of the companion to the central star of Abell 35
We report the results of a radial velocity study of BD - 22.3467 deg (LWHya), the cool companion to the subdwarf central star of the planetarynebula Abell 35. Estimates for its radial velocity have been obtained bycross correlation with radial velocity standards for five epochs ofobservations sampling periods of the order of days and decades. We findthat any radial velocity variation of BD - 22.3467 deg on periodsshorter than 30 d cannot possess a semi-amplitude greater than 5 km/s.Also, with the exception of a limited number of possible periods notcovered by our sampling frequency, we can exclude radial velocityvariations of semi-amplitude larger than about 8 km/s up to periods ofapproximately 30 yr. On the other hand, short-period,small-semi-amplitude about 5 km/s) radial velocity variations have beenobserved in the blue spectral region and possibly, with a smallersemi-amplitude (about 2 km/s), in the red. The photometric period of0.766 +/- 0.001 d, which has been associated with the rotation of thestar, is consistent with them, although other periods cannot yet beruled out.
| 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.
| The position corrections of 1400 stars observed with PA II in San Juan.
Not Available
| Gamma velocities of 58 faint Milky Way Cepheids
Using new radial velocity measurements of 47 faint southern hemisphereGalactic Cepheids, together with additional velocity data from Metzgeret al. (1991), gamma velocities are found for 58 low galactic latitudeCepheids. The gamma velocity is determined by using the period of aCepheid to generate a 'typical' velocity curve, then fitting the curveto the velocity measurements using two free parameters, the gammavelocity, and the phase. The velocity curve is generated using a secondorder Fourier series with coefficients determined from the period. Forthe Cepheids with observations that sample the velocity curve over avariety of pulsation phases, gamma velocities are determined to betterthan 1.0 km/s. Good agreement between these gamma velocities andpreviously published values where they exist.
| Fifth fundamental catalogue. Part 2: The FK5 extension - new fundamental stars
The mean positions and proper motions for 3117 new fundamental starsessentially in the magnitude range about 4.5 to 9.5 are given in thisFK5 extension. Mean apparent visual magnitude is 7.2 and is on average2.5 magnitudes fainter then the basic FK5 which has a mean magnitude of4.7. (The basic FK5 gives the mean positions and proper motions for theclassical 1535 fundamental stars). The following are discussed: theobservational material, reduction of observations, star selection, andthe system for the FK5 extension. An explanation and description of thecatalog are given. The catalog of 3117 fundamental stars for the equinoxand epoch J2000.0 and B1950.0 is presented. The parallaxes and radialvelocities for 22 extension stars with large forecasting effects aregiven. Catalogs used in the compilation of the FK5 fundamental catalogare listed.
| Progress toward a multiobject radial-velocity spectrometer
It is shown that it is possible to obtain stellar radial velocities ofhigh accuracy using a fiber-fed echelle spectrograph with no crossdisperser. Although the resulting spectrum contains many overlappingorders, the radial-velocity information is still present. Velocities maybe obtained by cross correlation with reference data obtained with thesame instrument. The accuracy is a function of the signal-to-noiseratio, and ranges from + or - 4 km/s to + or - 1 km/s. Velocities areobtained with exposure times just sufficient to obtain the barest traceof a spectrum using the same spectrograph and CCD detector with a crossdisperser. Thus, it appears possible to obtain precision similar to thatobtained with an order separator, but with considerably bettersensitivity, due to a multiplexing gain. Moreover, the overlappingorders of the stellar spectrum only occupy a few rows of the CCD. Usinga multiple-fiber-feed device, many such spectra could be fit on the CCD.This leads to the expectation of obtaining many radial velocitiessimultaneously using a multiobject spectrometer now under constructionat Cerro Tololo.
| The radio galaxy IC 4296 (PKS 1333-33). II. Spectroscopy, surface photometry, X-ray imaging, and infrared photometry
The authors present stellar rotation and velocity dispersion data,optical surface photometry, Einstein Observatory IPC X-ray data, andaperture (optical and infrared) photometry of the radio galaxy IC 4296.It is found that the projected stellar rotation axis is misaligned withthe projected radio axis by ?28°. The photometric major andminor axis surface brightness profiles of IC 4296 are well representedby King (1966) models in the range 3arcsec < r < 100arcsec. Thecentral mass-to-light ratio is M/LB = (13±3)h (hHubble constant in units of 100 km s-1Mpc-1). TheIPC X-ray image shows a slightly resolved source centered on IC 4296.Isothermal, hydrostatic atmospheres that are consistent with the X-raydata can be constructed.
| Radial velocities of southern stars obtained with the photoelectric scanner CORAVEL. II - Faint southern potential radial-velocity standards
Abstract image available at:http://adsabs.harvard.edu/abs/1984A&AS...57..275M
| 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.
| Lichtelektrische UBV-Photometrie von Standardsternen und in vier Sternfeldern am Äquator
Not Available
| Fundamental data for southern stars (Second List)
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1959MNRAS.119..638E&db_key=AST
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Pozíciós és asztrometriai adatok
| Csillagkép: | Kentaur |
| Rektaszcenzió: | 11h38m50.73s |
| Deklináció: | -45°21'45.2" |
| Vizuális fényesség: | 9.316 |
| RA sajátmozgás: | -20.1 |
| Dec sajátmozgás: | -79.4 |
| B-T magnitude: | 10.065 |
| V-T magnitude: | 9.378 |
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