תוכן
תמונות
הוסף תמונה שלך
DSS Images Other Images
מאמרים קשורים
The N2K Consortium. VII. Atmospheric Parameters of 1907 Metal-rich Stars: Finding Planet-Search Targets
We report high-precision atmospheric parameters for 1907 stars in theN2K low-resolution spectroscopic survey, designed to identify metal-richFGK dwarfs likely to harbor detectable planets. Of these stars, 284 arein the ideal temperature range for planet searches,Teff<=6000 K, and have a 10% or greater probability ofhosting planets based on their metallicities. The stars in thelow-resolution spectroscopic survey should eventually yield >60 newplanets, including 8-9 hot Jupiters. Short-period planets have alreadybeen discovered orbiting the survey targets HIP 14810 and HD 149143.
| The Pul-3 catalogue of 58483 stars in the Tycho-2 system
A catalogue of positions and proper motions of 58483 stars (Pul-3) hasbeen constructed at the Pulkovo observatory. The Pul-3 is based on theresults of measurements of photographic plates with galaxies (Deutsch'splan). All plates were taken using the Pulkovo Normal Astrograph (thefirst epoch is in the 1950s and the second epoch is in the 1970s).The Pul-3 catalogue contains stars of mainly 12 to 16.5 mag in 146fields with galaxies in the declination zone from -5o to+85o. The Tycho-2 has been used as a reference catalogue.The mean epoch of the Pul-3 is 1963.25. The internal positional accuracyof the Pul-3 catalogue at the mean epoch of observations is ±80mas. The accuracy of the proper motions is mostly within ±3mas/yr to ±12 mas/yr. Comparisons of the Pul-3 with Tycho-2 andARIHIP have been done at the mean epoch of the Pul-3. The Pul-3 externalpositional accuracy relative to Tycho-2 is ±150 mas.The catalogue is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/418/357
| GPM - compiled catalogue of absolute proper motions of stars in selected areas of sky with galaxies.
Not Available
| 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.
| Photometric survey near the main Galactic meridian: 2.1. Finding charts and photoelectric U,B,V,R stellar magnitudes in 26 fields. Photometric properties of the night sky at Mount Terskol observatory
Finding charts and photoelectric magnitudes of stars in the \ubvr\system in 26 fields of the MEGA programme are presented. This part ofthe photometric survey near the Main Galactic Meridian includes thefields with right ascentions 8(h) < alpha < 16(h) 30(m) anddeclinations -2(deg) < delta < 58(deg) . Together with the findingcharts of 2.5(deg) x2.5(deg) the equatorial coordinates of the stars aregiven for epoch and equinox 1950. Photometric properties of the nightsky at the Mount Terskol observatory near Mount Elbrus are derived fromthe photoelectric observations.
| Photometric Survey Near the Main Galactic Meridian - Part One - Photoelectric Stellar Magnitudes and Colours in the UBVR System
Not Available
| The evolution of the lithium abundances of solar-type stars. II - The Ursa Major Group
We draw upon a recent study of the membership of the Ursa Major Group(UMaG) to examine lithium among 0.3 Gyr old solar-type stars. For most Gand K dwarfs, Li confirms the conclusions about membership in UMaGreached on the basis of kinematics and chromospheric activity. G and Kdwarfs in UMaG have less Li than comparable stars in the Pleiades. Thisindicates that G and K dwarfs undergo Li depletion while they are on themain sequence, in addition to any pre-main-sequence depletion they mayhave experienced. Moreover, the Li abundances of the Pleiades K dwarfscannot be attributed to main-sequence depletion alone, demonstratingthat pre-main-sequence depletion of Li also takes place. The sun's Liabundance implies that the main-sequence mechanism becomes lesseffective with age. The hottest stars in UMaG have Li abundances likethose of hot stars in the Pleiades and Hyades and in T Tauris, and thetwo genuine UMaG members with temperatures near Boesgaard's Li chasmhave Li abundances consistent with that chasm developing fully by 0.3Gyr for stars with UMaG's metallicity. We see differences in theabundance of Li between UMaG members of the same spectral types,indicating that a real spread in the lithium abundance exists withinthis group.
|
הכנס מאמר חדש
לינקים קשורים
הכנס לינק חדש
משמש של הקבוצה הבאה
|
תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | אריה קטן |
| התרוממות ימנית: | 10h52m02.30s |
| סירוב: | +33°02'38.1" |
| גודל גלוי: | 8.739 |
| מרחק: | 72.516 פארסק |
| תנועה נכונה: | -48.9 |
| תנועה נכונה: | -62.2 |
| B-T magnitude: | 9.462 |
| V-T magnitude: | 8.799 |
קטלוגים וכינוים:
|
