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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
| Hipparcos red stars in the HpV_T2 and V I_C systems
For Hipparcos M, S, and C spectral type stars, we provide calibratedinstantaneous (epoch) Cousins V - I color indices using newly derivedHpV_T2 photometry. Three new sets of ground-based Cousins V I data havebeen obtained for more than 170 carbon and red M giants. These datasetsin combination with the published sources of V I photometry served toobtain the calibration curves linking Hipparcos/Tycho Hp-V_T2 with theCousins V - I index. In total, 321 carbon stars and 4464 M- and S-typestars have new V - I indices. The standard error of the mean V - I isabout 0.1 mag or better down to Hp~9 although it deteriorates rapidly atfainter magnitudes. These V - I indices can be used to verify thepublished Hipparcos V - I color indices. Thus, we have identified ahandful of new cases where, instead of the real target, a random fieldstar has been observed. A considerable fraction of the DMSA/C and DMSA/Vsolutions for red stars appear not to be warranted. Most likely suchspurious solutions may originate from usage of a heavily biased color inthe astrometric processing.Based on observations from the Hipparcos astrometric satellite operatedby the European Space Agency (ESA 1997).}\fnmsep\thanks{Table 7 is onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/397/997
| Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
| The 1.5-1.7 micrometer spectrum of cool stars: Line identifications, indices for spectral classification and the stellar content of the Seyfert galaxy NGC 1068
The first aim of this paper is to determine which lines or narrowmolecular bands in the H-band spectra of cool stars could be of interestfor the classification of K-M stars. For this purpose we present highquality, medium resolution (R approximates 1500) spectra of field stars(mostly K-M giants and supergiants) and compare them with detailedsynthetic spectra computed on the basis of existing model atmospheresfor red giants. The agreement between theoretical and observed spectrais good and virtually all the observed features can be accounted for bylines of (12)CO, (13)CO, OH, Mg, Al, Si, Ca and Fe. We analyze in detailthe relative contribution of these and other species and conclude thatthe feature at 1.62 micrometers which is weak in early K but very strongin late M stars, is mainly due to the CO(6-3) band-head, while that at1.59 micrometers, which is prominent in all stars later than G, isprimarily attributable to silicon up to early M types, while in late Mstars this feature is strongly contaminated by OH lines. We choose thesetwo features as 'spectral classificators' and measure their equivalentwidths in more than 40 G, K, M giants and supergiants. From these datait is found that CO 1.62 in giants increases rapidly and with arelatively small scatter going to later spectral types. Supergiants havedeeper CO(6-3) and display a larger scatter. The (1.62)/(2.29) ratiosteadily increases going to cooler stars but does not vary significantlywith luminosity class. A very useful ratio is (1.62)/(1.59) whichincreases by a large factor from early K to late M stars and couldtherefore be a powerful tool to identify and estimate the averagespectral type of cool stars in complex objects like active galaxynuclei. To demonstrate such a possibility we also present long slitspectra of the Seyfert galaxy NGC 1068 where the equivalent widths ofall stellar features are found to decrease in the central 4 arcsecaround the nucleus but the (1.62)/(1.59) ratio, and hence the averagestellar temperature, does not change significantly. The estimatedaverage spectral type is late-K which is compatible with either an oldand very metallic bulge population or a younger one associated with arecent starburst. These data also show that the non-stellar continuumaccounts for approximately 30% and approximately equal to or greaterthan 80% of the flux at 1.62 and 2.3 micrometers respectively in thecentral 4.4 arcsec. The features around 1.6 micrometers are thus muchless diluted than CO(2, 0) and hence offer advantages for studies of thestellar content in such objects. The non-stellar nuclear emission isvery red and most probably associated with a hot (T approximately equalor greater than 800 K) dust component.
| Optical polarization of stars of galactic latitudes b-45 degres.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976A&AS...23..125S&db_key=AST
| Radial Velocities, Spectral Types, and Luminosity Classes of 820 Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1950ApJ...112...48M&db_key=AST
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | לויתן |
| התרוממות ימנית: | 00h47m36.90s |
| סירוב: | -02°19'18.7" |
| גודל גלוי: | 7.179 |
| מרחק: | 862.069 פארסק |
| תנועה נכונה: | 12.1 |
| תנועה נכונה: | 4.6 |
| B-T magnitude: | 9.172 |
| V-T magnitude: | 7.344 |
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