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Pulkovo compilation of radial velocities for 35495 stars in a common system.
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| A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)
The LSPM catalog is a comprehensive list of 61,977 stars north of theJ2000 celestial equator that have proper motions larger than 0.15"yr-1 (local-background-stars frame). The catalog has beengenerated primarily as a result of our systematic search for high propermotion stars in the Digitized Sky Surveys using our SUPERBLINK software.At brighter magnitudes, the catalog incorporates stars and data from theTycho-2 Catalogue and also, to a lesser extent, from the All-SkyCompiled Catalogue of 2.5 million stars. The LSPM catalog considerablyexpands over the old Luyten (Luyten Half-Second [LHS] and New LuytenTwo-Tenths [NLTT]) catalogs, superseding them for northern declinations.Positions are given with an accuracy of <~100 mas at the 2000.0epoch, and absolute proper motions are given with an accuracy of ~8 masyr-1. Corrections to the local-background-stars propermotions have been calculated, and absolute proper motions in theextragalactic frame are given. Whenever available, we also give opticalBT and VT magnitudes (from Tycho-2, ASCC-2.5),photographic BJ, RF, and IN magnitudes(from USNO-B1 catalog), and infrared J, H, and Ks magnitudes(from 2MASS). We also provide an estimated V magnitude and V-J color fornearly all catalog entries, useful for initial classification of thestars. The catalog is estimated to be over 99% complete at high Galacticlatitudes (|b|>15deg) and over 90% complete at lowGalactic latitudes (|b|>15deg), down to a magnitudeV=19.0, and has a limiting magnitude V=21.0. All the northern starslisted in the LHS and NLTT catalogs have been reidentified, and theirpositions, proper motions, and magnitudes reevaluated. The catalog alsolists a large number of completely new objects, which promise to expandvery significantly the census of red dwarfs, subdwarfs, and white dwarfsin the vicinity of the Sun.Based on data mining of the Digitized Sky Surveys (DSSs), developed andoperated by the Catalogs and Surveys Branch of the Space TelescopeScience Institute (STScI), Baltimore.Developed with support from the National Science Foundation (NSF), aspart of the NASA/NSF NStars program.
| Magnesium Isotopic Abundance Ratios in Cool Stars
From high-resolution spectra of 61 cool dwarfs and giants, Mg isotopicabundance ratios 24Mg:25Mg:26Mg arederived from spectral synthesis of the MgH A-X lines near 5140 Å.Our sample spans the range -2.5<=[Fe/H]<=0.1, including the firstmeasurements of Mg isotope ratios in stars with metallicities below[Fe/H]=-2.0. We confirm the decrease in 25Mg/24Mgand 26Mg/24Mg with decreasing [Fe/H], as predictedby recent models of Galactic chemical evolution in which the Mg isotopesare produced in massive stars. A subset of kinematically identifiedthin-disk stars have Mg isotope ratios in excellent agreement with thepredictions. Within the measurement uncertainties, these thin-disk starsshow no scatter about the predictions. Several of our stars are likelymembers of the thick disk, and their high Mg isotopic ratios may reflectthe nucleosynthetic history of the thick disk, which is distinct fromthe predictions for, and observations of, the thin disk. For thick-diskand halo stars we find a scatter in 25Mg/24Mg and26Mg/24Mg exceeding our measurement uncertaintiesand increasing with increasing metallicity. Our data suggest that anadditional source of 25Mg and 26Mg is required.Intermediate-mass asymptotic giant branch stars are likely candidates.
| A Search for Cool Subdwarfs: Stellar Parameters for 134 Candidates
The results of a search for cool subdwarfs are presented. Kinematic (U,V, and W) and stellar parameters (Teff, logg, [Fe/H], andξt) are derived for 134 candidate subdwarfs based onhigh-resolution spectra. The observed stars span 4200K
| Improved Astrometry and Photometry for the Luyten Catalog. II. Faint Stars and the Revised Catalog
We complete construction of a catalog containing improved astrometry andnew optical/infrared photometry for the vast majority of NLTT starslying in the overlap of regions covered by POSS I and by the secondincremental Two Micron All Sky Survey (2MASS) release, approximately 44%of the sky. The epoch 2000 positions are typically accurate to 130 mas,the proper motions to 5.5 mas yr-1, and the V-J colors to0.25 mag. Relative proper motions of binary components are measured to 3mas yr-1. The false-identification rate is ~1% for11<~V<~18 and substantially less at brighter magnitudes. Theseimprovements permit the construction of a reduced proper-motion diagramthat, for the first time, allows one to classify NLTT stars intomain-sequence (MS) stars, subdwarfs (SDs), and white dwarfs (WDs). We inturn use this diagram to analyze the properties of both our catalog andthe NLTT catalog on which it is based. In sharp contrast to popularbelief, we find that NLTT incompleteness in the plane is almostcompletely concentrated in MS stars, and that SDs and WDs are detectedalmost uniformly over the sky δ>-33deg. Our catalogwill therefore provide a powerful tool to probe these populationsstatistically, as well as to reliably identify individual SDs and WDs.
| 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.
| Photometry of dwarf K and M stars
An observational program using UBVRI photometry is presented for 688stars from among the dwarf K and M stars already found spectroscopicallyby Vyssotsky (1958). Of these, 211 have not been observedphotometrically. These observations were obtained over a period ofseveral years at the Kitt Peak National Observatory using a GaAsphotomultiplier with an 0.9 m reflector. Based on night-to-nightvariations in the measures of individual stars, the internal errors maybe estimated to be roughly 0.01 mag for the colors and 0.015 for the Vmagnitudes. The photometric parallaxes reported for each star werecomputed in the manner discussed by Weis (1986).
| VRI photometry of late dwarf common proper motion pairs
VRI photometry and photometric distance moduli are presented for 266late dwarf common proper motion pairs. From the distance modulusdifferences between the components of each pair, it is inferred that atleast 56 percent of the pairs contain one or more additional stellarcomponents. The maximum separation of M dwarf binaries appears to be ofthe order 10,000-20,000 AU.
| The incidence of close binaries among stars of low mass Astrophysical binaries
Using a single-stage Varo image tube at the coude spectrograph of theLick Observatory, the authors obtained multiple spectrograms of 48 dMstars and 15 dMe stars, centered at H-alpha, with a reciprocaldispersion of about 17 A/mm. The results of precise measurements of theradial velocities of these stars, and of an analysis to search forlow-amplitude binaries in the sample are reported. Evidence for two newbinaries is found in the sample of dMe stars, and none in the sample ofdM stars. It is argued that it may not be possible for an M-dwarf starto be a component in a binary system with a period of less than 5 dwithout being so active as to produce Balmer line emission. The Galactickinematics of the sample is displayed, giving further support to thenotion that the dMe stars may be a young subset of all M dwarfs, andfurther suggesting that they may all be associated with the Pleiadessupercluster.
| Dwarf K and M stars of high proper motion found in a hemispheric survey
A recently completed visual/red spectral region objective-prism surveyof more than half the sky found some 2200 dwarf K and M stars ofnegligible proper motion (Stephenson, 1986). The present paper adds the1800-odd spectroscopically identified dwarfs that did prove to havesignificant proper motions. About half of these had previous spectralclassifications of some sort, especially by Vyssotsky (1952, 1956). Forthe great majority, the present coordinates are more accurate thanprevious data. The paper includes about 50 stars with unpublishedparallaxes, likely to have parallaxes of 0.05 arcsec or more. Combiningthe present data with the first paper suggests that the number oflow-proper-motion stars in that paper was not unreasonable.
| New subdwarfs. IV - UBV photometry of 1690 high-proper-motion stars
A photometric list of 1690 stars of known high proper motion is used tosearch for potential high-velocity stars of various metallicity valuesin order to find candidates for trigonometric programs on subdwarfs andto enlarge the sample with which to study the relation between stellarkinematics and metal abundance. A list of 113 stars with tangentialspace velocities of 300 km/s or greater is obtained, the highesttangential velocity relative to the sun being 630 km/s. By using thevariation of the tangential velocity with longitude and adopting thegalactic rotation at the solar circle to be 220 km/s, the rotation ofthe subdwarf system is estimated at 0 + or - 50 km/s from the transversevelocity alone, in agreement with determinations based on other methods.
| 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
| Rapid rotation and H-alpha emission anomalies among some members of the population of low-mass stars
The paper reports on some important anomalous phenomena which werediscovered during a systematic investigation of the properties oflow-mass (M dwarf) stars. It is found that the single M dwarfs GLS 410and GLS 179 have a diluted H-alpha absorption line. It is suggested thatthis is due to weak plage activity and that these stars are in atransition state between the chromospherically active dMe and theinactive dM state. It is found that the dMe star GLS 890 is a rapidlyrotating single M dwarf with v sin i of approximately 70 km/s andpredicted that it should have a photometric wave with about 8 hr period.It is found that the Joy and Abt 'dMe' assignment is in error not onlyfor GLS 179 but also for GLS 176, GLS 611.3, and GLS 908. The 'dMe'assignment for BD + 12.2201 deg is problematic and may be due tomisidentification.
| Spectral types for proper motion stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975AJ.....80..239B&db_key=AST
| Spectral Types of M Dwarf Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974ApJS...28....1J&db_key=AST
| Lowell proper motions II : proper motion survey of the Northern Hemisphere with the 13-inch photographic telescope of the Lowell Observatory
Not Available
| Photoelectric observations of red dwarf stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956AJ.....61..213M&db_key=AST
| The radial velocities of 166 red dwarf stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1954AJ.....59..218D&db_key=AST
| Dwarf M. Stars Found Spectrophotometrically-Third List.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1952ApJ...116..117V&db_key=AST
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Membre dels grups següents:
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Dades d'Observació i Astrometria
| Constel·lació: | Leo |
| Ascensió Recta: | 10h22m20.48s |
| Declinació: | +12°08'45.2" |
| Magnitud Aparent: | 10.166 |
| Distancia: | 35.702 parsecs |
| Moviment propi RA: | -308.5 |
| Moviment propi Dec: | -31 |
| B-T magnitude: | 11.887 |
| V-T magnitude: | 10.309 |
Catàlegs i designacions:
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