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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.
| Finding Cool Subdwarfs Using a V-J Reduced Proper-Motion Diagram: Stellar Parameters for 91 Candidates
We present the results of a search for cool subdwarfs for which ourcandidates were drawn from a V-J reduced proper-motion diagramconstructed by Salim & Gould. Kinematic (U, V, and W) andself-consistent stellar parameters (Teff, logg, [Fe/H], andξt) are derived for 91 candidate subdwarfs based onhigh-resolution spectra. The observed stars span 3900K
| 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.
| Revised Coordinates and Proper Motions of the Stars in the Luyten Half-Second Catalog
We present refined coordinates and proper-motion data for the highproper-motion (HPM) stars in the Luyten Half-Second (LHS) catalog. Thepositional uncertainty in the original Luyten catalog is typicallygreater than 10" and is often greater than 30". We have used the digitalscans of the POSS I and POSS II plates to derive more accurate positionsand proper motions of the objects. Out of the 4470 candidates in the LHScatalog, 4323 objects were manually reidentified in the POSS I and POSSII scans. A small fraction of the stars were not found because of thelack of finder charts and digitized POSS II scans. The uncertainties inthe revised positions are typically ~2" but can be as high as ~8" in afew cases, which is a large improvement over the original data.Cross-correlation with the Tycho-2 and Hipparcos catalogs yielded 819candidates (with mR<~12). For these brighter sources, theposition and proper-motion data were replaced with the more accurateTycho-2/Hipparcos data. In total, we have revised proper-motionmeasurements and coordinates for 4040 stars and revised coordinates for4330 stars. The electronic version of the paper5 contains the updated information on all 4470stars in the LHS catalog.
| Chemical Compositions of Four Metal-poor Giant Stars
We present the chemical compositions of four K giants (CS 22877-1, CS22166-16, CS 22169-35, and BS 16085-0050) that have [Fe/H] in the range-2.4 to -3.1. Metal-poor stars with [Fe/H]<-2.5 are known to exhibitconsiderable star-to-star variations of many elements. This quartetconfirms this conclusion. CS 22877-1 and CS 22166-16 are carbon-rich.There is significant spread of [α/Fe] within our samples, where[α/Fe] is computed from the mean of the [Mg/Fe] and [Ca/Fe]ratios. BS 16085-0050 is remarkably α-enriched with a mean[α/Fe] of +0.7, but CS 22169-35 is α-poor. The aluminumabundance also shows a significant variation over the sample. A paralleland unsuccessful search among high-velocity late-type stars formetal-poor stars is described.
| Photometry of Stars with Large Proper Motion
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996AJ....112.2300W&db_key=AST
| UBVRI photoelectric photometry of high proper motion stars
UBVRI photoelectric photometry is presented for 269 late spectral type,high proper motion stars belonging to the 'Lowell Proper Motion Survey'and included in the present version of the Hipparcos Input Catalogue.The observations and data reduction are described. The external errorsobtained by comparison of the results with those obtained in otherstudies are presented.
| High-tangential-velocity stars
Two lists of high tangential velocity (greater than 100 km/s) starscontained in the Lowell Northern Hemisphere proper motion surveycatalogue have been compiled, the stellar distances being inferred fromeither trigonometric or spectroscopic parallaxes. The information givenincludes equatorial coordinates, corrected photographic magnitudes,proper motions, trigonometric or spectroscopic parallaxes, and spectraltypes.
| Spectral classification of high-proper-motion stars
Spectral types have been found for about 900 stars of high proper motioncontained in the Lowell Observatory Northern Hemisphere proper-motionstar survey using all blue-region objective prism plates. The spectralclassification criteria are given. About eighty stars of largetangential velocity have been classified using slit spectrograms takenwith a 36-in. reflector. A new calibration of Luyten's absolutemagnitude vs reduced proper motion relation is made, and its dependenceon spectral type is investigated.
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| Takýmyýldýz: | Buyuk Ayi |
| Sað Açýklýk: | 11h34m35.62s |
| Yükselim: | +40°09'22.7" |
| Görünürdeki Parlaklýk: | 11.119 |
| özdevim Sað Açýklýk: | -435.9 |
| özdevim Yükselim: | -491 |
| B-T magnitude: | 11.876 |
| V-T magnitude: | 11.182 |
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