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מאמרים קשורים
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.
| A photometric study of wide visual double stars. II - Common proper motion double stars
A total of 82 common proper motion wide visual double stars have beenobserved using the uvby, H-beta systems. MK class, color excess,absolute magnitude, effective temperature, and distance have beenderived from calibrations of the above systems. From the distancesderived here and the astrometric data, taken from the literature, it wasfound that the percentage of physical binaries among the common propermotion wide double stars is significantly higher than the samepercentage among the wide visual double stars with significant relativeproper motion, but there are a lot of optical pairs among them as well.
| A second list of wide visual binaries
Not Available
| A second list of wide visual binaries
Not Available
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הכנס מאמר חדש
לינקים קשורים
הכנס לינק חדש
משמש של הקבוצה הבאה
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | דלי |
| התרוממות ימנית: | 23h06m39.24s |
| סירוב: | -14°51'49.6" |
| גודל גלוי: | 9.167 |
| תנועה נכונה: | 154.3 |
| תנועה נכונה: | 49.6 |
| B-T magnitude: | 9.915 |
| V-T magnitude: | 9.229 |
קטלוגים וכינוים:
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