The Dushak-Erekdag Survey of roAp Stars
The search of roAp stars at Mt. Dushak-Erekdag Observatory was startedin 1992 using the 0.8 m Odessa telescope equipped with a two-starhigh-speed photometer. We have observed more than a dozen stars so farand discovered HD 99563 as roAp star while BD +8087 is suspected to haverapid oscillations. Negative results of our observations for the searchof rapid oscillations in four stars in NGC 752 are also discussed.
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Eight New Magnetic Stars with Large Continuum Depressions
Observations with the 6-m telescope revealed eight new magnetic,chemically peculiar stars: HD 29925, HD 40711, HD 115606, HD 168796, HD178892, HD 196691, HD 209051, and BD +32o2827. Zeemanobservations of all these objects have been carried out for the firsttime. We selected candidates by analyzing the depression profile at awavelength of lambda 5200 A. This technique for selecting candidatemagnetic stars was shown to be efficient: we found magnetic fields in 14of the 15 objects that we selected for our observations with a Zeemananalyzer. A maximum longitudinal field strength B_e exceeding 8 kG wasfound in HD 178892; in HD 209051 and HD 196691, B_e reaches 3.3 and 2.2kG, respectively. For the remaining stars, we obtained lower limits ofthe longitudinal field (more than several hundred G).
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Rapidly oscillating Ap stars versus non-oscillating Ap stars
The positions in the HR diagram and the kinematic characteristics ofrapidly oscillating and non-oscillating chemically peculiar stars areobtained using new Hipparcos proper motions and parallaxes, and our ownradial velocity measurements. We find that rapidly oscillating stars, asa group, are (-0.47 +/- 0.34) mag above the zero-age main sequence(ZAMS), while the non-oscillating stars are (-1.20 +/- 0.65) mag abovethe ZAMS and so appear slightly more evolved on average. From thecomparison of the kinematical characteristics, we conclude that bothgroups are very similar. The results of radial velocity measurementsindicate that there is a real deficiency of binaries among rapidlyoscillating stars. Presently, no such star is known to be aspectroscopic binary.
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Radial velocities. Measurements of 2800 B2-F5 stars for HIPPARCOS
Radial velocities have been determined for a sample of 2930 B2-F5 stars,95% observed by the Hipparcos satellite in the north hemisphere and 80%without reliable radial velocity up to now. Observations were obtainedat the Observatoire de Haute Provence with a dispersion of 80Ä,mm(-1) with the aim of studying stellar and galactic dynamics.Radial velocities have been measured by correlation with templates ofthe same spectral class. The mean obtained precision is 3.0 km s(-1)with three observations. A new MK spectral classification is estimatedfor all stars. Based on observations made at the Haute ProvenceObservatory, France and on data from The Hipparcos Catalogue, ESA.Tables 4, 5 and 6 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr or viahttp://cdsweb.u-strasbg.fr/Abstract.htm
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Observations of roAp stars at the Mt. Dushak-Erekdag station of Odessa Astronomical Observatory
Since 1992, observations of roAp stars have been carried out using thedual-channel photometer attached to the 0.8m telescope, which issituated in Central Asia, at the Mt. Dushak-Erekdag station of OdessaAstronomical Observatory. Some results of observations of gamma Equ andof HD 134214 are presented. 5 stars were investigated as roApcandidates. The Fourier spectra of 4 stars did not show any variabilityin the high-frequency region. The Fourier spectrum of HD 99563 revealeda peak at a frequency f=128.9 c/d and with a semi-amplitude of 3.98mmag.
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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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The Cape rapidly oscillating AP star survey - III. Null results of searches for high-overtone pulsation.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1994MNRAS.271..129M&db_key=AST
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A new list of effective temperatures of chemically peculiar stars. II.
Not Available
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Photoelectric UVBY beta photometry of 230 stars brighter than m(pg) = 13.0 in the two B = +75 deg fields SA 80 and SA 81
The study presents uvby and beta photometry for 123 and 107 stars in SA80 and SA 81 brighter than m(pg) = 13 and earlier than G1. Most starsseem to be of type A or F with sample limits V is not greater than 12.6and beta is not less than 2.60. SA 80 and SA 81 have 34 and 27 BD starsin common with a general b is not less than 70 deg program,respectively. uvby photometry for 19 and 12 stars fainter than m(pg) =13 is also presented. If situated on the standard line, the sample ofabsolutely less luminous F9-G0 stars are complete in the volume confinedto the distance range from 80 to 300-400 pc. Several lines of sight haveE(b-y) exceeding 0.050 m. In both areas the remote A stars seem to bevirtually unreddened or are perhaps bluer than typical for population Istars. SA 80 covers part of the Virgo cluster, and the data may be usedto estimate the galactic reddening in this direction.
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Photoelectric photometry of stars near the north Galactic pole. II
UBV photometric observations of about 700 stars near the north Galacticpole, obtained using single-channel photometers on the 40-cm and 60-cmCassegrain telescopes at Kvistaberg Observatory (during 1976-1983) andthe Spanish International Observatory (during 1984), respectively, aspart of a program including the stars to be observed by the Hipparcosspacecraft, are reported. The data are presented in a series of tablesand briefly characterized.
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UBV sequences in six of Kapteyn's Selected Areas
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&AS...12...85H&db_key=AST
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Interstellar reddening near the north galactic pole
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972PASP...84..497F&db_key=AST
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The Motions of the A Stars at the North Galactic Pole
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969PASP...81..741E&db_key=AST
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The galactic force law K(z
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969AJ.....74..139P&db_key=AST
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INHABITED SKY
