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מאמרים קשורים
The HR-diagram from HIPPARCOS data. Absolute magnitudes and kinematics of BP - AP stars
The HR-diagram of about 1000 Bp - Ap stars in the solar neighbourhoodhas been constructed using astrometric data from Hipparcos satellite aswell as photometric and radial velocity data. The LM method\cite{luri95,luri96} allows the use of proper motion and radial velocitydata in addition to the trigonometric parallaxes to obtain luminositycalibrations and improved distances estimates. Six types of Bp - Apstars have been examined: He-rich, He-weak, HgMn, Si, Si+ and SrCrEu.Most Bp - Ap stars lie on the main sequence occupying the whole width ofit (about 2 mag), just like normal stars in the same range of spectraltypes. Their kinematic behaviour is typical of thin disk stars youngerthan about 1 Gyr. A few stars found to be high above the galactic planeor to have a high velocity are briefly discussed. Based on data from theESA Hipparcos astrometry satellite and photometric data collected in theGeneva system at ESO, La Silla (Chile) and at Jungfraujoch andGornergrat Observatories (Switzerland). Tables 3 and 4 are onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| The Cape rapidly oscillating AP star survey - III. Null results of searches for high-overtone pulsation.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1994MNRAS.271..129M&db_key=AST
| Speckle interferometry of HIPPARCOS link stars. III
A third list of stars is presented which have been tested by speckleinterferometry for use in the Hubble Space Telescope link between theHipparcos astrometric reference frame and the extragalactic VLBIreference frame. Structural information on angular scales of 0.15-1.2arcsec for 34 Southern Hemisphere stars is reported from observationsmade with the Imperial College Speckle Interferometer mounted on theMount Stromlo 1.9-m telescope. Twenty-four percent of the stars (8 outof the 34) show evidence of multiplicity, in agreement with previousobservations in this program.
| A catalogue of QSOs and link stars for the HST link of the HIPPARCOS reference frame
A list of bright (less than 17 mag) southern QSOs and bright (less than11 mag) stars that may be suitable for the Hubble Space Telescope linkbetween the Hipparcos astrometric reference frame and the VLBIextragalactic frame is presented. The QSOs have been selected fromvarious lists of radio objects and identifications. The stars have beenselected from the Strasbourg (CDS) data base and from the PreliminarySecond Cape Photographic Catalog, and supplemented with stars measuredfrom the SERC IIIa-J Schmidt survey. These QSOs and stars have beenincluded in the Hipparcos and HST schedule of observations.
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לינקים קשורים
הכנס לינק חדש
משמש של הקבוצה הבאה
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | אוקטנט |
| התרוממות ימנית: | 00h39m15.34s |
| סירוב: | -83°01'58.5" |
| גודל גלוי: | 8.356 |
| מרחק: | 271.003 פארסק |
| תנועה נכונה: | 4.2 |
| תנועה נכונה: | -6.5 |
| B-T magnitude: | 8.549 |
| V-T magnitude: | 8.372 |
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