Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
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Polarimetric Studies of Stars with an Infrared Emission Excess
The results of polarimetric and IR (IRAS) observations of 24 B-A-F starsare given. Intrinsic polarization of the light from 11 of the 24 starsis observed. The degree of polarization for the other 13 stars is withinthe measurement errors. Two-color diagrams are also constructed. From acomparison of the degree of polarization with the color index on thetwo-color diagrams it is seen that 8 of these 13 stars probably are ofthe Vega type, while 5 are stars with gasdust shells and/ordiskshells. It is shown that 6 of the aforementioned 11 starswith intrinsic polarization evidently are stars with gasdustshells and/or diskshells, while 5 of them (also including No. 24)are of the Vega type. It is also shown that the IR emission from 10 ofthe stars corresponds to a power-law distribution F . This fact may beexplained both by freefree transitions of electrons and bythermal emission from dust grains in circumstellar gasdust shells(disks).
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GasDust Shells around Some Early-Type Stars with an IR Excess (of Emission)
The results of an investigation of IR (IRAS) observations of 58OBAF stars of different luminosity classes, whichare mainly members of various associations, are presented. The colorindices of these stars are determined and two-color diagrams areconstructed. The emission excesses at 12 and 25 mm (E 12 and E 25) arealso compared with the absorption A1640 of UV radiation. It is concludedthat 24 stars (of the 58 investigated) are disk systems of the Vegatype, to which Vega = N 53 also belongs. Eight known stars of the Vegatype are also given in the figures for comparison. The remaining 34stars may have gasdust shells and/or shelldisks. The IRemission excesses of the 34 investigated stars and 11 comparison stars(eight of them are Be-Ae stars) are evidently due both to thermalemission from grains and to the emission from freefreetransitions of electrons in the gasdust shells of these stars.
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Classification and properties of UV extinction curves
The catalog of Savage et al. (\cite{ref27}) reporting colour excesses of1415 stars from ANS photometry offers the opportunity to deeplyinvestigate the characteristics of UV extinction curves which differfrom the standard extinction of the diffuse interstellar medium. To thisaim we have selected a sample of 252 curves, which have been comparedwith the relations derived by Cardelli et al. (\cite{ref4}; CCM in thefollowing) for a variety of R_V values in the range 2.4-5 and have beenclassified as normal if they fit at least one of the CCM curves oranomalous otherwise. We find that normal curves with small R_V are justas numerous as those with large R_V. The anomalous objects are arrangedinto two groups according to the strength of the bump at 0.217 mu . Fora given value of c_2 this increases along the sequence: type Aanomalous, normals and type B anomalous, suggesting that this sequenceshould correspond to an increase of the amount of small grains along thesightline. Considerations concerning the environmental characteristicsindicate that the anomalous behaviour is not necessarily tied to theexistence of dense gas clouds along the line of sight.
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UBV beta Database for Case-Hamburg Northern and Southern Luminous Stars
A database of photoelectric UBV beta photometry for stars listed in theCase-Hamburg northern and southern Milky Way luminous stars surveys hasbeen compiled from the original research literature. Consisting of over16,000 observations of some 7300 stars from over 500 sources, thisdatabase constitutes the most complete compilation of such photometryavailable for intrinsically luminous stars around the Galactic plane.Over 5000 stars listed in the Case-Hamburg surveys still lackfundamental photometric data.
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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.
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Intrinsic colour indices of O- and B- type stars in the Vilnius photometric system.
Not Available
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SAO stars with infrared excess in the IRAS Point Source Catalog
We have undertaken a search for SAO stars with infrared excess in theIRAS Point Source Catalog. In contrast to previous searches, the entireIRAS (12)-(25)-(60) color-color diagram was used. This selection yieldeda sample of 462 stars, of which a significant number are stars withcircumstellar material. The stars selected can be identified aspre-main-sequence stars, Be stars, protoplanetary systems, post-AGBstars, etc. A number of objects are (visual) binary stars.Characteristic temperatures and IR excesses are calculated and theirrelations to spectral type are investigated.
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Photoelectric photometry of OB stars in the Vilnius system
Not Available
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A spectral survey of early-type stars in the region of Cassiopeia using an objective prism
Not Available
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The interstellar 217 NM band - A third catalogue of equivalent widths
A catalog of equivalent widths of the 217 nm interstellar absorptionband as well as other parameters characterizing the extinction curve inthe ultraviolet has been compiled for 790 O and B stars. A relativelytight correlation between the equivalent width of the 217 nm band andE(B-V) indicates that the absorber of this band is connected with thepopulation of larger interstellar grains responsible for the visualextinction. The parameter characterizing the amount of extinction in thefar UV is only weakly correlated with E(B-V), a result in accord withthe assumption that a second population of very small grains causes therapid increase of the far-UV extinction.
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A catalog of ultraviolet interstellar extinction excesses for 1415 stars
Ultraviolet interstellar extinction excesses are presented for 1415stars with spectral types B7 and earlier. The excesses with respect to Vare derived from Astronomical Netherlands Satellite (ANS) 5-channel UVphotometry at central wavelengths of approximately 1550, 1800, 2500, and3300 A. A measure of the excess extinction in the 2200-A extinction bumpis also given. The data are valuable for investigating the systematicsof peculiar interstellar extinction and for studying the character of UVinterstellar extinction in the general direction of stars for which theextinction-curve shape is unknown.
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Ultraviolet interstellar extinction toward 1367 stars observed by ANS
Five-band UV photometry is used to investigate the character ofinterstellar extinction toward 1367 stars of spectral type B3 andearlier, with observations producing a galactic average of 5.11, 4.78,6.52, 4.10 and 1.95 at 1550, 1800, 2200, 2500, and 3300 A, respectively.Differences in the strengths of the UV extinction features of thesestars appear to be independent, since objects with either strong or weak2200 A extinction can have strong, normal or weak far-UV extinction.Further investigation reveals that some of the deviant stars areembedded in localized regions whose average extinction curves divergedramatically from the galactic mean. The anomalous extinction of theseregions attests to localized inhomogeneities in the UV characteristicsof interstellar dust. Because the evaluation of UV extinction toward aparticular star would be more accurate if based on the average curve ofthe region immediately surrounding that star rather than that of theentire Galaxy, it is recommended that the galactic average presented beused with caution to correct astronomical data of individual objects.
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21-cm observations of nonplanar H I associated with the Perseus spiral arm
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977AJ.....82..886G&db_key=AST
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Four-color and H beta photometry of the galactic cluster NGC 6633.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976PASP...88...63S&db_key=AST
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Catalogue d'etoiles O et B.
Not Available
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Photoelectric 4430 A observations of 506 O, B and A stars.
Not Available
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Photoelectric observations of the intensity of the 4430 band in 147 O, B, and A stars in the Northern Milky Way.
Not Available
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Photoelectric observations of the intensity of the 4430 band in 147 O,B, and A stars in the Northern Milky Way
Not Available
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Studies in Galactic STRUCTURE.II.LUMINOSITY Classification for 1270 Blue Giant Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1955ApJS....2...41M&db_key=AST
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Carbon Stars at the Galactic Equator in a Zone 4° Wide.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1954ApJ...120..129N&db_key=AST
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Polarization of Stellar Radiation. III. The Polarization of 841 Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...114..241H&db_key=AST
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A Finding List of O and B Stars of High Luminosity.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...113..141N&db_key=AST
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Intensities of the Interstellar Band at λ 4430.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...113..100D&db_key=AST
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INHABITED SKY
