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Pulkovo compilation of radial velocities for 35495 stars in a common system. Not Available
| Photometric and Spectroscopic Study of Stars in the Field of the Young Open Cluster Roslund 4 We present photometric and spectroscopic observations performed in thefield of the Galactic open cluster Roslund 4, which contains the twocataloged nebulae IC 4954 and IC 4955. UBVRI photometry was carried outin a field of 11'×6' around the clustercenter. Medium-resolution optical spectroscopy has been obtained for 41stars, including previously selected main-sequence and pre-main-sequencecandidate cluster members. Narrowband Hα, [S II], and continuumimages have been secured. The observations allow us the measurement ofdifferent physical parameters for the cluster. Assuming an absorptioncoefficient AV/E(B-V)=3.1 and a reddening slopeE(U-B)/E(B-V)=0.72, we obtain a color excess E(B-V)=1.1+/-0.2 and adistance modulus DM0=11.7+/-0.5. Fitting of isochrones to thecolor-magnitude diagrams gives logage(yr)=7.2+/-0.2, and thespectroscopic measurements provide the value VR=-15.7+/-5.2km s-1 for the heliocentric radial velocity. Among the 41stars with spectroscopic data, 11 stars are probable cluster members onthe basis of their radial velocity, and another 10 are considered aspossible members. Two probable member stars of spectral types A5 and G1show hints of absorption in the Li I 6708 Å line, with respectiveequivalent widths of 0.10 and 0.28 Å, and 22 stars of spectraltypes from B2 to G0 show different degrees of emission in Hα, [NII], and [S II] lines. With the exception of three stars of spectraltype earlier than A0, the emission of which is mainly photospheric, allother emissions seen in Hα and forbidden lines have a nebularorigin. They arise in an ionized cloud that surrounds the cluster and iscausing diffuse emission and, possibly, local variations in theextinction law from star to star. In addition to the stars, spectra ofseveral nebular condensations with relatively higher excitation havebeen analyzed. Two of them have been suggested to be Herbig-Haro (HH)objects. Our spectra indicate that only one of these condensations couldbe considered as an HH object.
| 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.
| Spectral classification and UBV H BET photometry. Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977ApJ...213..105D&db_key=AST
| Les vitesses radiales obtenues à l'aide d'un grand prisme objectif de 40 cm de diamètre. Etude cinématique et photométrique d'un champ galactique Not Available
| La mesure des vitesses radiales au prisme objectif. IX - 3e liste de vitesses radiales déterminées au prisme objectif à vision directe Not Available
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תצפית ומידע אסטרומטרי
קבוצת-כוכבים: | קאסיופיאה |
התרוממות ימנית: | 23h27m54.26s |
סירוב: | +59°41'43.1" |
גודל גלוי: | 7.567 |
מרחק: | 180.505 פארסק |
תנועה נכונה: | -34.5 |
תנועה נכונה: | -12.3 |
B-T magnitude: | 7.865 |
V-T magnitude: | 7.592 |
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