New beta Cephei and SPB Stars Discovered in Hipparcos Photometry
We discuss 34 stars for which we detected new frequencies in HipparcosHp magnitudes. 13 of these stars are variables discovered in this paper.For 20 stars, we derive log T_eff and log g from Stromgren or Genevaphotometry.We classify one new beta Cep star, HIP 88352, two new beta Cep suspects,HIP 54753 and 88123, four new SPBs, HIP 1030, 39206, 46192 and 111147,and two SPB suspects, HIP 75787 and 98778. We find the last star to betriply-periodic and we show that the frequencies detected in Hpmagnitudes are present in the photoelectric observations of Hill etal(1976).Finally, we discover the hottest variable of the SPB type, namely, HIP1030.
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The total-to-selective extinction ratio determined from near IR photometry of OB stars
The paper presents an extensive list of the total to selectiveextinction ratios R calculated from the infrared magnitudes of 597 O andB stars using the extrapolation method. The IR magnitudes of these starswere taken from the literature. The IR colour excesses are determinedwith the aid of "artificial standards" - Wegner (1994). The individualand mean values of total to selective extinction ratios R differ in mostcases from the average value R=3.10 +/-0.05 - Wegner (1993) in differentOB associations. The relation between total to selective extinctionratios R determined in this paper and those calculated using the "methodof variable extinction" and the Cardelli et al. (1989) formulae isdiscussed. The R values presented in this paper can be used to determineindividual absolute magnitudes of reddened OB stars with knowntrigonometric parallaxes.
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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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UV Cas: Photometry, Polarization, and Spectrum near Maximum Light
The UBV observations of UV Cas during 1996-1999 show mostly irregularlight variations. The VB light variations on time scales from one day totwo weeks have a smaller amplitude than those on longer time scales. Theamplitude of the UBV light variations on time scales from 20 to 200 daysreaches 0.4, 0.3, and 0.2 mag, respectively. The colors of UV Cas do notcorrespond to G5 supergiants, but are more similar to the colors of G0 Istars at substantial U-B color excesses. A comparison of the energydistribution for UV Cas, as constructed from the broadband UBVRIobservations in 1982, with the energy distribution for G0 supergiantsreveals enhanced near-infrared and ultraviolet emission, which can beattributed to unusual chemical composition of the star. The polarizationof light from UV Cas in quiescence is mainly interstellar in origin,although the presence of weak intrinsic polarization produced by thegas-dust circumstellar medium cannot be ruled out either. The strengthof CI lines in the spectrum of UV Cas confirms that it belongs to R CrBstars, as well as the conclusion of Orlov and Rodriguez that carbon isappreciably overabundant. The atmospheric metal underabundance in UV Casmay be larger than has been thought previously. The line broadening issigma = 10.7 km/s. The star's effective temperature appears to be higherthan 5500 K. The radial velocity of UV Cas measured from metal andcarbon lines is -31.17 +/- 0.38 km/s. The NaI D lines have a splitprofile, with the two absorbing clouds observed toward UV Cas atdistances < 1 kpc and 1.5-2.5 kpc from the Sun contributing to itscomponents.
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Polarimetric observations of some stars with an infrared (emission) excess.
Not Available
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Catalogue of H-alpha emission stars in the Northern Milky Way
The ``Catalogue of Stars in the Northern Milky Way Having H-alpha inEmission" appears in Abhandlungen aus der Hamburger Sternwarte, Band XIin the year 1997. It contains 4174 stars, range {32degr <= l() II< 214degr , -10degr < b() II < +10degr } having the Hαline in emission. HBH stars and stars of further 99 lists taken from theliterature till the end of 1994 were included in the catalogue. We givethe cross-identification of stars from all lists used. The catalogue isalso available in the Centre de Données, Strasbourg ftp130.79.128.5 or http://cdsweb.u-strasbg.fr and at the HamburgObservatory via internet.
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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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Catalogue of stars in the northern Milky Way having H-alpha in emission
Not Available
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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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Spectroscopic and Polarimetric Observations of the Nova Cassiopeiae 1993
Not Available
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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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Observation of interstellar polarization at 2.2 and 3.8 microns
Interstellar linear polarization has been observed in the K (2.2 micron)and L-prime (3.8 micron) bands for 30 stars. The K band resultsgenerally agree with the previous measurements. The L-primepolarization, obtained for the first time, is larger for most stars thanSerkowski's (1974) and Wilking's (1980) empirical formulas predict. Fromthese observations, a power-law dependence of polarization of aboutwavelength exp-2 in the wavelength range of 1.25-2.2 microns isproposed; this dependence is similar to that of interstellar extinction.The decrease of polarization from K to L-prime is even slower than thispower-law. This might be also similar to the extinction law, butconfirmation by further observations is necessary.
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An optical spiral arm beyond the Perseus arm
In the second galactic quadrant, optical spiral arm tracers have beencollected in a systematic literature search. A uniform reduction of thedata led to the detection of a distinct structure (probably a spiralarm) beyond the Perseus arm that is separated by a statisticallysignificant gap from the latter.
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Miscellaneous spectroscopic notes
Results of slit-spectrograph observations are reported for approximately260 stars. The data presented range from recognition of many new Ap, Am,and other unusual stars to H-alpha observations of early-typesupergiants and Be stars. The material discussed was obtained over thepast 40 years at a number of U.S. observatories and at the DominionAstrophysical Observatory in Victoria, B.C.
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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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Interstellar extinction curve - The profile of very broad structure
The interstellar extinction curve between 3500 and 10,500 A isdetermined from a series of two-color plots based on existing spectralscans. Very Broad Structure (VBS) covers the wavelength range from 5000to 8000 A and consists of three components centered at 5300, 5900 and6800 A. The VBS is shown to originate in the same agent as that ofcontinuous extinction.
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Observations of interstellar diffuse absorption band at 4430 A
Observations of the interstellar diffuse absorption band at 4430 A for800 O and B stars in Neckel's (1967) catalog are being carried out, and482 spectra obtained up to September 1983 have been reduced. It isconfirmed that the strength of the interstellar diffuse absorption bandat 4430 A does not simply relate to the abundance of interstellar grainson the line of sight. The relation between the color excess E(B-V) andthe equivalent width of the band to the direction of l = 130-140 deg andb = -5 to +5 deg shows that some parameter(s) other than E(B-V) is (are)needed to understand the cause of this band.
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Catalog of O-B stars observed with Tokyo Meridian Circle
A catalog of the O-B stars, selected from 'Blaauw-Parenago' list andRubin's catalog, has been compiled on the FK4 system by the observationsmade with Gautier 8-inch Meridian Circle at the Tokyo AstronomicalObservatory during the period, 1971 to 1979. It contains 1059 stars andwas compiled for the future establishment of high precision propermotions of O-B stars.
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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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Additional Variable Stars in the Northern Luminous Stars Catalogues
Not Available
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A survey of interstellar neutral potassium. I - Abundances and physical conditions in clouds toward 188 early-type stars
Observations of interstellar absorption in the resonance doublet 7664,7698 A of neutral potassium toward 188 early-type stars at a spectralresolution of 8 km/s are reported. The 7664 A line is successfullyseparated from nearly coincident telluric O2 absorption for all but afew of the 165 stars for which K I absorption is detected, makingpossible an abundance analysis by the doublet ratio method. Therelationships between the potassium abundances and other atomicabundances, the abundance of molecular hydrogen, and interstellarreddening are investigated.
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List of 333 variable, microvariable or suspected variable stars detected in the Geneva photometry
A list is presented of 333 stars, excluded from the GCVS and itssupplements, whose probability of variability ranges from high tocertain. The standard deviations observed in the V magnitude togetherwith the known spectral types, however, only allow speculation as to thetype of variable in question pending supplementary observations whichreveal the individual characteristics of these stars.
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The wavelength dependence of interstellar linear polarization - Stars with extreme values of lambda/max/
Infrared polarimetry of 13 stars with predominantly extreme values ofmaximum wavelength, less than 0.47 or more than 0.67 microns, haspermitted a more accurate determination of the wavelength dependence ofinterstellar linear polarization from 0.30 to 2.2 microns. Combining thenew data with previous data results in an improved description of thevariation of K with maximum wavelength from 32 stars. Infraredpolarimetry of Kappa Cas can be combined with existing ultraviolet andoptical polarimetry to suggest that the broadening of the normalizedlinear polarization curve in the near ultraviolet is significant forstars with maximum wavelength of less than 0.55 microns.
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A catalogue of stellar spectrophotometric data
A list of 378 sets of stellar energy distributions for 356 stars basedon photoelectric spectrophotometry is presented. Data from eight sourceshave been transformed to the Hayes-Latham calibration of Alpha Lyrae.The procedure follows that of Breger (1976) and the present list extendsprevious data, especially for stars of earliest and intermediatespectral types.
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The physical properties and orbital parameters of the B0 IA star HD 152667 = V861 Scorpii - A supergiant with a black hole companion
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1979ApJ...230..519W&db_key=AST
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Spectrophotometry of Kappa Cassiopeiae /BC0.7 Ia/ and HD 188209 /O9.5 Iab/
The spectrophotometry of the bright OBC star Kappa Cassiopeiae and ofthe normal supergiant HD 188209 is examined. The energy distributions ofthe stars were measured in the spectral region 3300-7100 with the HCOScanner on the no. 1 92-cm telescope at Kitt Peak. For Kappa Cas, theCrawford (1978) method based on Stromgren color indices yields E(B - V)= 0.40 mag and the Q method using Johnson color indices yields 0.44 mag;for Hd 188209 the two methods yield 0.17 mag and 0.22 mag, respectively.Upon comparing the dereddened fluxes with the predictions of Kurucz's(1979) full-line-blanketed, plane-parallel model atmospheres with solarabundances to obtain the brightness temperatures found, the best fit forKappa Cas with E(B - V) = 0.40 mag occurs for T(eff) = 30,000 K, log g =3.5. The best fit for HD 188209 with E(B - V) = 0.17 mag is T(eff)30,000 K, log g = 3.5, where the star is brighter than the modellongward of 6400 A.
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Infrared colors and the diffuse interstellar bands
Broad-band infrared photometric measurements have been gathered for 105stars which exhibit diffuse interstellar bands in their spectra. Allnormal stars obey a single reddening law, and a value of R equal to 3.08+ or - 0.15 is derived. This value is consistent with other recentdeterminations of R. The diffuse band indicators, the central depth ofthe 4430-A feature and the equivalent widths of the 5780-A and 6284-Afeatures, show as large a scatter with the infrared color excesses asthey do with E(B - V). No single-valued relation between the colorexcesses and the diffuse band strengths appears to exist. This castsdoubt on whether dust grains which produce the visual and infraredextinctions are the carriers for the diffuse interstellar features.
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Radial velocities and distances of OB stars at the solar distance to the galactic centre.
Abstract image available at:http://adsabs.harvard.edu/abs/1976MNRAS.176..683C
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INHABITED SKY
