Contents
Images
Upload your image
DSS Images Other Images
Related articles
Completeness of USNO-B for High Proper Motion Stars
I test the completeness of USNO-B detections of high proper motion(μ>180 mas yr-1) stars and the accuracy of itsmeasurements by comparing them to the revised New Luyten Two-Tenthscatalog of Salim & Gould. For 14.5~20 mas yr-1) may actuallyhave still larger errors than tabulated.
| 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.
| Radial Velocities of Population II Stars. II.
A program for radial velocity measurements of Population II stars wasstarted in 1988 and was carried out during six observing runs. Theprogram includes metal-deficient stars, components of Population IIvisual binaries or common proper motion stars, suspected radial velocityvariables and the Population II stars from the Hipparcos program. Themeasurements were made with the 1 meter reflector at the MaidanakObservatory in Uzbekistan. The average error of a single measurement isabout 0.6 km/s, but for stars at 13 mag or for extremely metal-deficientstars the error is about 2.5 km/s. The catalog contains 621 measurementsfor 164 stars.
| GPM1 - a catalog of absolute proper motions of stars with respect to galaxies
The description of the first version of the General Compiled Catalogueof Absolute Proper Motions (GPM1) for a sample of HIPPARCOS stars,derived with respect to galaxies within the plan called Catalogue ofFaint Stars (KSZ, Deutch 1952), is presented. The principal aim of theGPM1 construction was to provide absolute proper motions of stars todetermine the rotation of the HIPPARCOS system. The GPM1 cataloguecontains 977 HIPPARCOS Input Catalogue stars with V magnitudes $5^m -11^m in 180 fields north of -25 degrees of declination. The accuracy ofthe proper motions is 8 mas/yr (milliarcseconds per year). Comparison ofproper motions of GPM1 with those of the PPM and ACRS was performed andanalyzed with respect to systematic errors caused by spurious rotationof the FK5 system. The standard errors show that the rotation may bedetermined with an accuracy better than 1 mas/yr. Catalog is onlyavailable in electronic form at the CDS via anonymous ftpcdsarc.u-strasbg.fr or ftp 130.79.128.5.
| GPM - compiled catalogue of absolute proper motions of stars in selected areas of sky with galaxies.
Not Available
| Radial velocities of Population II stars. I
Radial velocity measurements are presented for 81 Population II stars.The sample comprises components of metal-poor binary stars,spectroscopic binary candidates, high latitude supergiants,metal-deficient stars with spectroscopic determinations of Fe/H,HIPPARCOS program stars, and some other stars of metal-poor population.The radial velocity measurements were made in February 1988 with aphotoelectric stellar velocimeter.
| Subluminous stars. III. Luminosity calibration for subluminous stars and the space density of the blue subluminous stars south of declination - 45 degres
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969ApJ...157..287E&db_key=AST
| Einige stärker bewegte Sterne in Coma und Virgo
Not Available
|
Submit a new article
Related links
Submit a new link
Member of following groups:
|
Observation and Astrometry data
| Constellation: | Coma Berenices |
| Right ascension: | 12h32m20.77s |
| Declination: | +13°35'01.8" |
| Apparent magnitude: | 9.855 |
| Proper motion RA: | -274.5 |
| Proper motion Dec: | -5.9 |
| B-T magnitude: | 10.663 |
| V-T magnitude: | 9.922 |
Catalogs and designations:
|
