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מאמרים קשורים
FAUST far ultraviolet observations of Shapley's wing in the SMC-LMC bridge.
The Small Magellanic Cloud-Large Magellanic Cloud (SMC-LMC) bridge hasbeen the subject of a limited number of studies. It is the closestbridge among a number of known intergalactic bridges situated in groupsof galaxies. Because of tidal interactions, star formation is likely tobe very active in these bridges, and the details of these interactionscan be investigated through the study of hot stars; UV wide-fieldtelescopes are especially suited to this class of work. A new suchobservation of the SMC in the far UV (1400-1800A) was obtained with theFAUST telescope (SSL, Berkeley; LAS, Marseille) flown aboard the spaceshuttle in March, 1992 as part of the ATLAS-1 mission. A previousdetection by the Very-Wide-Field Camera (VWFC; LAS, Marseille) aboardSpacelab-1 revealed the stellar UV contribution of the Shapley Wing ofthe SMC in the direction of the LMC. The much deeper (4.6 magnitudes)FAUST observations, with a resolution thrice better than that of theVWFC, confirm this extension as part of the bridge and allow a clearidentification of 29 UV-bright stars with known opticalspectrophotometry and radial velocities.
| Positional reference stars in the Magellanic Clouds
The equatorial coordinates are determined of 926 stars (mainly ofgalactic origin) in the direction of the Magellanic Clouds at the meanepoch T = 1978.4 with an overall accuracy characterized by the meanvalues of the O-C coordinates, Sa = 0.35 arcsec and Sd = 0.38 arcsec,calculated from the coordinates of the Perth reference stars. Thesevalues are larger than the accuracy expected for primary standard stars.They allow the new positions to be considered as those of reliablesecondary standard stars. The published positions correspond to anunquestionable improvement of the quality of the coordinates provided inthe current catalogs. This study represents an 'astrometric step' in thestarting of a 'Durchmusterung' of the Magellanic Clouds organized by deBoer (1988, 1989).
| Early type high-velocity stars in the solar neighborhood. IV - Four-color and H-beta photometry
Results are presented from photometric obaservations in the Stromgrenuvby four-color and H-beta systems of early-type high-velocity stars inthe solar neighborhood. Several types of photometrically peculiar starsare selected on the basis of their Stromgren indices and areprovisionally identified as peculiar A stars, field horizontal-branchstars, metal-poor stars near the Population II and old-disk turnoffs,metal-poor blue stragglers, or metallic-line A stars. Numerousphotometrically normal stars were also found.
| Early-type high-velocity stars in the solar neighborhood. III - Radial velocities, rotation indices, and line-strength indices for southern candidates
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983AJ.....88.1349S&db_key=AST
| Early-type high-velocity stars in the solar neighborhood. I - List of candidates
Suspected nearby high-velocity stars of spectral types B and A areidentified by their proper motions, which are generally too small forthe stars to have been included in previous catalogs of high-velocitystars. The same selection process is then extended to spectral type Fstars, in order to both provide a companion sample and investigatewhether the hypothetical high-velocity, metal-rich population continuesto later spectral types. Of the presented list of 371 stars withconfirmed proper motions, 168 are of A and B spectral types. Photometricand spectroscopic observations of these stars are required to eliminatethose with misclassified spectra and convert proper motions into spacevelocities. The identification of type of stars is important forunderstanding apparent exceptions to the correlation between stellarages, metal abundances, and kinematic properties.
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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: | נחש מים קטן |
| התרוממות ימנית: | 01h50m24.31s |
| סירוב: | -73°46'13.3" |
| גודל גלוי: | 8.544 |
| מרחק: | 212.766 פארסק |
| תנועה נכונה: | 52.2 |
| תנועה נכונה: | 19.6 |
| B-T magnitude: | 8.826 |
| V-T magnitude: | 8.568 |
קטלוגים וכינוים:
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